JPH0767341A - Start controller for power converter - Google Patents

Abstract

PURPOSE:To obtain a start controller for a power converter preventing the overload usage of an initial charging circuit and the increase of loss by AC currents flowing among two systems or more of PWM converters. CONSTITUTION:DC voltage is charged to a DC smoothing capacitor 7 by initial charging circuits 4, 5, and AC voltage is generated from a PWM converter 1. On the other hand, a zero-voltage control signal from a zero-voltage control signal generator 22 is outputted to a converter DC voltage controller 15 through a control signal changer 23 by a synchronous controller 12, a converter AC current controller 17 outputs a voltage control signal bringing AC currents to zero under the off state of DC voltage control, and the synchronous controller 12 generates a voltage control signal Ecs synchronizing the sum Vc of AC voltage with a system voltage signal Vs. Accordingly, both voltage control signals are added by an adder 24, and AC voltage synchronized with system voltage is generated while AC currents flowing between PWM converters 1a and 1b are controlled in zero by a pulse width modulation control circuit 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a start-up control device for a power converter, and particularly to a voltage-type PWM (pulse width modulation control) converter having two or more systems connected to a power system side. The present invention relates to a startup control device for a power converter for initial startup control of a power converter.

[0002]

2. Description of the Related Art When a voltage type PWM converter (hereinafter, simply referred to as a PWM converter unless otherwise specified) is linked to a power supply system side, for example, a DC voltage source which is an initial charging circuit is used to initially charge a DC input side voltage of the PWM converter. There is a method of generating an AC voltage by PWM-controlling the DC voltage by a PWM converter, synchronizing it with the system voltage of the commercial power supply system, and then cooperating with the power supply system side. At the time of synchronous control with the system voltage, the system voltage is detected, a voltage control signal that is synchronized with the system voltage is created, and the PWM converter is PWM-controlled based on the voltage control signal. I am trying to generate a voltage.

FIG. 9 shows, for example, the 1992 IEEJ Transactions D,
112, Volume 1, No. 1, conventional P shown in P29 to P37
FIG. 1 is a configuration diagram of a start-up control device for a WM converter, which includes a main circuit for only one system for DC output and a control circuit for pre-merge synchronization with a power system side. In FIG. 9, 1
Is a PWM converter, 2 is a converter transformer, 3 is a circuit breaker for linking the PWM converter 1 with the power system side through the converter transformer 2, and 4 is a link before linking the PWM converter 1 with the power system side. An initial charging rectifier 5 for applying a DC voltage to the PWM converter 1 and an initial charging transformer 5 forming an initial charging circuit together with the initial charging rectifier 4;
6 connects the initial charging rectifier 4 to the power system side via the initial charging transformer 5 during initial charging, and connects the initial charging rectifier 4 via the initial charging transformer 5 to the power system after system cooperation. A circuit breaker for disconnecting the circuit from the side, and 7 is a DC smoothing capacitor provided on the DC output side of the PWM converter 1.

Reference numeral 8 is a DC voltage detector for detecting a DC voltage output from the PWM converter 1, and reference numeral 9 is an AC provided between the converter transformer 2 and the circuit breaker 3 for detecting an AC current of the PWM converter 1. A current detector, 10 is a system voltage detector that detects the system voltage of the power supply system, 11 is an AC voltage detector that detects the AC voltage generated on the system side of the converter transformer 2, and 12 is a system voltage before integration. The circuit breaker 3 of the main circuit is turned off and the circuit breaker 6 is turned on by the switching timing signal τ, and the DC charging capacitor 7 is turned on by the initial charging circuit.
Is charged with a direct current voltage, and the direct current voltage is pulse-width modulated by the PWM converter 1 to operate the PWM converter 1 as an inverter to generate an alternating voltage Vc on the converter transformer 2 side of the circuit breaker 3 to generate a system voltage Vs. And a voltage control signal E _cs for synchronizing the AC voltage Vc with a control signal switching device 18 of a control circuit, which will be described later, selects the synchronization controller 12 side and outputs it to the pulse width modulation control circuit 20. is there.

Reference numeral 13 is a DC voltage reference setter, 14 is a subtractor for taking the difference between the DC voltage signal detected by the DC voltage detector 8 and the DC voltage reference set signal set by the DC voltage reference setter 13, and 15 Is a converter DC voltage controller for obtaining an AC current reference value (converter input current reference value) for controlling the DC voltage output from the PWM converter 1 based on the output of the subtractor 14, and 16 is an AC current detector 9. A subtracter 17 that takes the difference between the detected AC current signal and the AC current reference value output from the converter DC voltage controller 15, and 17 controls the voltage to a pulse width modulation control circuit 20 described later based on the output of the subtracter 16. It is a converter alternating current controller that delivers a signal E _cv .

Reference numeral 18 is a synchronization controller 1 before the system connection based on the switching timing signal τ output from the synchronization controller 12.
The control signal switching is performed so that the voltage control signal E _cs output from 2 is switched to the voltage control signal E _cv output from the converter AC current controller 17 after the system is inserted into the pulse width modulation control circuit 20. Reference numeral 19 is a triangular wave generator for generating a triangular wave, and 20 is a pulse width modulation control circuit for performing pulse width modulation control of the voltage control signal input through the control signal switch 18 by the triangular wave output from the triangular wave generator 19. The PWM converter 1 is controlled by the gate pulse signal output from the pulse width modulation control circuit 20.

Next, the operation of the above configuration will be described. First, before the system is connected, the circuit breaker 3 is turned off and the circuit breaker 6 is turned on in the main circuit by the switching timing signal τ output from the synchronous controller 12, and the switching timing signal τ in the control circuit. Thus, the control signal switch 18 selects the side of the synchronous controller 12, and the voltage control signal E _cs output from the synchronous controller 12 is output to the pulse width modulation control circuit 20. In the main circuit, the DC voltage is charged in the DC smoothing capacitor 7 by the initial charging rectifier 4 via the initial charging transformer 5, and the DC voltage is pulse width modulated by the PWM converter 1 to control the converter. An AC voltage Vc is generated on the converter transformer 2 side of the circuit breaker 3 via the transformer 2 for use.

The AC voltage Vc is detected by the AC voltage detector 11, the system voltage Vs is detected by the system voltage detector 10, and the system voltage V is detected by the synchronous controller 12.
A voltage control signal E _cs for synchronously controlling s and the AC voltage Vc is generated and output to the pulse width modulation control circuit 20 via the control signal switcher 18. The pulse width modulation control circuit 20 outputs a gate pulse signal for controlling the PWM converter 1 by comparing the voltage control signal E _cs with the triangular wave output from the triangular wave generator 19, and the gate pulse signal The PWM converter 1 generates a PWM AC voltage synchronized with the system voltage.

In this way, if the system voltage and the PWM AC voltage waveform output from the PWM converter 1 are synchronized, the switching timing signal τ output from the synchronization controller 12 causes the circuit breaker 3 in the main circuit. When the circuit breaker 6 is turned on and the circuit breaker 6 is turned off, the control signal switch 18 also outputs the voltage control signal E _cv output from the converter AC current controller 17 to the pulse width modulation control circuit 20. The control is switched to the one after the system is connected.

After the system is connected, the subtractor 14 subtracts the difference between the DC voltage signal detected by the DC voltage detector 8 and the DC voltage reference setting signal set by the DC voltage reference setting unit 13.
The converter DC voltage controller 15 outputs the converter AC current reference value corresponding to the difference. Then, the difference between the converter AC current reference value and the converter AC current signal detected by the converter AC current detector 9 is obtained by the subtractor 16 and input to the converter AC current controller 17, whereby voltage control is performed as an output. The signal E _cv is sent to the pulse width modulation control circuit 20 via the control signal switch 18. The pulse width modulation control circuit 20 outputs the voltage control signal E _cv to the triangular wave generator 19
The pulse width modulation control is performed by the triangular wave generated by to generate the gate pulse signal, the PWM converter 1 is controlled, and the DC voltage control and the AC current control are performed.

FIG. 10 is a block diagram showing the start-up control device of the PWM converter when the DC output of the PWM converter 1 is provided in two systems. In FIG. 10, 1-2
0 is the same as that in FIG. 9, and the alphabetical letter a added after the numeral as the code is the first PWM converter system, b
Relates to the second PWM converter system, and for example, 7a is a DC smoothing capacitor of the first PWM converter 1a system. Further, as a new configuration, reference numeral 21 is a proportional calculator that halves the voltage control signal E _CS output from the synchronization controller 12.

As the operation related to the configuration shown in FIG. 10, the control performed in the configuration shown in FIG. 9 is performed for two systems, and the same operation is performed. However, the voltage control signal output from the synchronization controller 12 is halved by the proportional calculator 21 and output to the control signal switcher 18. This is because the voltage for synchronizing with the power supply system side is the sum of the AC voltage generated by the P-side PWM converter 1a and the AC voltage generated by the N-side PWM converter 1b. This is because an AC voltage that is ½ the system voltage is generated.

Here, before the system is connected, that is, when the circuit breaker 3 is OFF, the first PWM converter 1a is used.
And the second PWM converter 1b are connected via the first converter transformer 2a and the second converter transformer 2b to form a circulation circuit. In this case, the first
AC voltage generated by the PWM converter 1a and the second P
If the AC voltage generated by the WM converter 1b has the same waveform, there is no exchange of current between the two converter systems, and the DC voltage between the two converter systems can be combined in the system while being balanced.

Further, FIG. 11 is a block diagram showing a start-up control device of a PWM converter in another case in which two DC outputs of the PWM converter are provided. In FIG. 11, 1
10 to 20 are the same as those in FIG. 10, the alphabetical letters a added after the numerals as symbols are related to the first PWM converter system, and b is related to the second PWM converter system,
For example, 7a is a DC smoothing capacitor of the first PWM converter 1a system.

The structure shown in FIG. 11 differs from the structure shown in FIG. 10 in that an initial charging rectifier 4 and an initial charging transformer 5 are provided corresponding to the first and second PWM converter systems. The operation is the same as that shown in FIG. 10.

[0016]

Since the conventional startup control device for the PWM converter is configured as described above, it has the following problems. (1) For example, a conventional P configured as shown in FIG.
In the start-up control device for the WM converter, the first and second PWM converters 1a and 1b are connected via the converter transformers 2a and 2b before the system is combined.
When performing pulse width modulation control, in order to remove harmonic components from the converter output, the triangular waves as carrier signals output from the triangular wave generator 19 to the pulse width modulation control circuits 20a and 20b are 180 ° out of phase. Due to the phase difference of the carrier signals, the same difficulty of offset adjustment in each control circuit of the two systems of the first and second PWM converters 1a and 1b, and the same timing of each control signal in each control circuit of the two systems. When there is a difference between the AC voltage waveforms generated by the first and second PWM converters 1a and 1b due to difficulty in initial soft start, etc., a converter is provided between the first and second PWM converters 1a and 1b. An alternating current will flow through the transformers 2a and 2b.

When this alternating current flows, the inflow of electric power from one of the initial charging circuits consisting of the initial charging rectifier 4 and the initial charging transformer 5 to the other PWM converter via the PWM converter can occur. Occurs, which causes one of the initial charging circuits to supply electric power that is equal to or higher than the rated value, which causes an overload in the initial charging circuit, and the loss of the PWM converter and the converter transformer due to the current flowing between the PWM converters. Could increase the loss.

(2) In addition, for example, in the conventional start-up control device for the PWM converter configured as shown in FIG. 11, the PWM converters 1a and 1b are connected to the converter transformers 2a and 2b before the grid connection. Are connected via the PWM converter 1 in the same manner as in the case of FIG.
When there is a difference between the AC voltage waveforms generated by a and 1b, an AC current flows between the PWM converters via the converter transformer.

The flow of this alternating current may cause the inflow of electric power from one PWM converter into the other PWM converter, which increases the output DC voltage of the PWM converter into which the electric power flows. The output DC voltage of the PWM converter where the power flows out drops,
As a result, the output DC voltage of the PWM converter may be unbalanced, resulting in overvoltage and undervoltage.

The present invention has been made to solve the above-mentioned problems, and in the initial start-up control of PWM converters of two or more systems, the overload use state of the initial charging circuit and the PWM converters of two or more systems. It is an object of the present invention to obtain a start-up control device for a power converter that can prevent an increase in loss due to an alternating current flowing through the power converter and can perform system integration while balancing the DC voltage applied from the initial charging circuit.

[0021]

A startup control device for a power converter according to claim 1 of the present invention is a converter for two or more systems connected in parallel to a commercial power supply system via a first circuit breaker. And two or more systems of initial charging in which the DC output side is connected to the commercial power supply system in parallel via a second circuit breaker, and the DC output side is connected to the DC output side of the converter via a DC smoothing capacitor. A circuit, an AC current detecting means for detecting an AC current of each converter, a system voltage detecting means for detecting a system voltage of the commercial power supply system, an AC voltage detecting means for detecting an AC voltage of the converter, and A DC voltage reference setter for transmitting a DC voltage reference set value, and a switching tie according to before and after system connection are provided. Signal is sent, the first circuit breaker is turned off and the second circuit breaker is turned on before the system is connected, and the DC smoothing capacitor is charged by the initial charging circuit to operate the converter as an inverter. To generate an AC voltage, and to send a voltage control signal for synchronously controlling the system voltage by the system voltage detection means and the AC voltage by the AC voltage detection means, and when synchronized, turn on the first circuit breaker. A synchronous controller for turning on the second circuit breaker and turning on the second circuit breaker, a DC voltage detected by the DC voltage detecting means, and a DC voltage reference set by the DC voltage reference setting device. Converter DC voltage control of two or more systems, each of which outputs a control signal for controlling the DC voltage output from each converter based on the deviation from the set value. And two or more systems of converter AC current controllers for sending voltage control signals for controlling the AC current respectively based on the deviation between the output of the converter DC voltage controller and the output of the AC current detecting means. In a start-up control device for a power converter, which includes a control circuit having two or more systems of pulse width modulation control means for performing pulse width modulation control of each converter based on an input control signal, a zero converter is provided in the control circuit. A zero voltage control signal generator for sending a voltage control signal, and a control signal based on the zero voltage control signal is given to each converter AC current controller based on the switching timing signal from the synchronous controller before system integration. By including a control signal switch, the commercial power supply system while controlling the AC current of each converter to zero based on the zero voltage control signal. It is characterized in that the voltage synchronized with the system voltage is controlled to be output to the AC side of each converter.

A starting control device for a power converter according to a second aspect of the present invention includes two or more converters connected in parallel to a commercial power supply system via a first circuit breaker, and the commercial power supply system. On the other hand, two or more systems of initial charging circuits are connected in parallel via the second circuit breaker, and the DC output side is connected to the DC output sides of the converters via DC smoothing capacitors, respectively, and the converters AC current detecting means for detecting AC current, system voltage detecting means for detecting system voltage of the commercial power supply system, AC voltage detecting means for detecting AC voltage of the converter, and DC voltage of each converter. With a DC voltage detecting means, a DC voltage reference setter for sending out a DC voltage reference set value, and a switching timing signal according to before and after system integration, Before the integration, the first circuit breaker is turned off, the second circuit breaker is turned on, the DC smoothing capacitor is charged by the initial charging circuit, and the converter is operated as an inverter to generate an AC voltage. A voltage control signal is generated to synchronously control the system voltage by the system voltage detection means and the AC voltage by the AC voltage detection means, and when synchronized, the first circuit breaker is turned on and the first circuit breaker is turned on. Turn off circuit breaker 2
Output from each of the converters on the basis of a synchronous controller to be inserted in the system, and a deviation between the DC voltage detected by the DC voltage detecting means and the DC voltage reference set value set by the DC voltage reference setter. Two or more systems of converter DC voltage controllers for sending control signals for controlling the DC voltage, and AC currents based on the deviation between the output of the converter DC voltage controller and the output of the AC current detecting means. Two or more systems of converter AC current controllers for sending voltage control signals for controlling, and two or more systems of pulse width modulation control means for respectively performing pulse width modulation control on the converters based on the input control signals. In a start-up control device for a power converter including a control circuit having the same, a zero-voltage control signal generation for sending a zero-voltage control signal to the control circuit. Prior to system integration, a first control signal switching device for providing the zero voltage control signal to each converter DC voltage controller based on a switching timing signal from the synchronous controller, and one of the converter systems. A second control signal switching device for providing the converter AC current controller with the zero voltage control signal, and a signal supply device for providing the voltage control signal by the synchronous controller only to the pulse width modulation control device of the converter system. Thus, the AC voltage control system and the AC current control system are controlled without interfering with each other.

Further, according to a third aspect of the present invention, there is provided a startup control device for a power converter in which two or more converters connected in parallel to the commercial power system via a first circuit breaker and the commercial power system. On the other hand, two or more systems of initial charging circuits are connected in parallel via the second circuit breaker, and the DC output side is connected to the DC output sides of the converters via DC smoothing capacitors, respectively, and the converters AC current detecting means for detecting AC current, system voltage detecting means for detecting system voltage of the commercial power supply system, AC voltage detecting means for detecting AC voltage of the converter, and DC voltage of each converter. With a DC voltage detecting means, a DC voltage reference setter for sending out a DC voltage reference set value, and a switching timing signal according to before and after system integration, Before the integration, the first circuit breaker is turned off, the second circuit breaker is turned on, the DC smoothing capacitor is charged by the initial charging circuit, and the converter is operated as an inverter to generate an AC voltage. A voltage control signal is generated to synchronously control the system voltage by the system voltage detection means and the AC voltage by the AC voltage detection means, and when synchronized, the first circuit breaker is turned on and the first circuit breaker is turned on. Turn off circuit breaker 2
Output from each of the converters on the basis of a synchronous controller to be inserted in the system, and a deviation between the DC voltage detected by the DC voltage detecting means and the DC voltage reference set value set by the DC voltage reference setter. Two or more systems of converter DC voltage controllers for sending control signals for controlling the DC voltage, and AC currents based on the deviation between the output of the converter DC voltage controller and the output of the AC current detecting means. Two or more systems of converter AC current controllers for sending voltage control signals for controlling, and two or more systems of pulse width modulation control means for respectively performing pulse width modulation control on the converters based on the input control signals. In a start-up control device for a power converter including a control circuit having the same, a zero-voltage control signal generation for sending a zero-voltage control signal to the control circuit. Prior to system integration, a first control signal switching device for providing the zero voltage control signal to each converter DC voltage controller based on a switching timing signal from the synchronous controller, and one of the converter systems. A second control signal switching device for providing the converter AC current controller with the zero voltage control signal, and a signal supply device for providing the voltage control signal by the synchronous controller only to the pulse width modulation control device of the converter system. Thus, the AC voltage control system and the AC current control system are controlled without interfering with each other, and each converter AC current controller is composed of a proportional calculator and an integral calculator, and each converter outputs After the AC voltage to be controlled becomes a constant voltage, the control signal is switched through the second control signal switching device which switches based on the switching timing signal from the synchronous controller. A voltage control signal based on the deviation between the output of the barter DC voltage controller and the output of the AC current detection means is output to the proportional calculator side of the converter AC current controller, and the AC current output by each converter is constant. And a third control signal switcher for outputting the voltage control signal to the integration calculator side of the converter AC current controller after the value becomes the value.

[0024] According to a fourth aspect of the present invention, there is provided a startup control device for a power converter in which two or more converters are connected in parallel to the commercial power supply system via a first circuit breaker and the commercial power supply system. On the other hand, one system of initial charging circuit connected in parallel via a second circuit breaker, and having a DC output side connected to a DC output side of the converter via a DC smoothing capacitor, and an AC of each converter. AC current detecting means for detecting a current, system voltage detecting means for detecting a system voltage of the commercial power supply system, AC voltage detecting means for detecting an AC voltage of the converter, and DC for detecting a DC voltage of each converter. In addition to the voltage detection means, a DC voltage reference setter that sends out a DC voltage reference set value, and a switching timing signal according to before and after system integration, Before turning on, the first circuit breaker is turned off, the second circuit breaker is turned on, the DC smoothing capacitor is charged by the initial charging circuit, and the converter is operated as an inverter to generate an AC voltage. A voltage control signal for synchronously controlling the system voltage by the system voltage detection means and the AC voltage by the AC voltage detection means is transmitted, and when synchronized, the first circuit breaker is turned on, and the second circuit breaker is turned on. Based on the difference between the DC voltage detected by the DC voltage detection means and the DC voltage reference set value set by the DC voltage reference setting device, a synchronous controller for turning off the circuit breaker and inserting the system in parallel. Converter DC voltage controllers of two or more systems, each of which outputs a control signal for controlling the DC voltage output from each converter, and the converter DC Two or more systems of converter AC current controllers for sending voltage control signals for controlling AC currents based on the deviation between the output of the pressure controller and the output of the AC current detecting means, and the input voltage control signal. In a start-up control device for a power converter having a control circuit having two or more systems of pulse width modulation control means for performing pulse width modulation control of each converter based on Control signal switcher for giving a signal based on the deviation of the DC voltage detected by the converter to the converter DC voltage controller, and a voltage control signal output from the converter AC current controller for voltage control from the synchronous controller. And adding means for adding the respective signals and sending them to the respective pulse width modulation control means.

[0025] According to a fifth aspect of the present invention, there is provided a startup control device for a power converter in which two or more converters are connected in parallel to the commercial power supply system via a first circuit breaker and the commercial power supply system. On the other hand, one system of initial charging circuit connected in parallel via a second circuit breaker, and having a DC output side connected to a DC output side of the converter via a DC smoothing capacitor, and an AC of each converter. AC current detecting means for detecting a current, system voltage detecting means for detecting a system voltage of the commercial power supply system, AC voltage detecting means for detecting an AC voltage of the converter, and DC for detecting a DC voltage of each converter. A voltage detecting means is provided, a DC voltage reference setter that sends out a DC voltage reference set value, and a switching timing signal according to before and after system connection Before turning on, the first circuit breaker is turned off, the second circuit breaker is turned on, the DC smoothing capacitor is charged by the initial charging circuit, and the converter is operated as an inverter to generate an AC voltage. A voltage control signal for synchronously controlling the system voltage by the system voltage detection means and the AC voltage by the AC voltage detection means is transmitted, and when synchronized, the first circuit breaker is turned on, and the second circuit breaker is turned on. Based on the difference between the DC voltage detected by the DC voltage detection means and the DC voltage reference set value set by the DC voltage reference setting device, a synchronous controller for turning off the circuit breaker and inserting the system in parallel. Converter DC voltage controllers of two or more systems, each of which outputs a control signal for controlling the DC voltage output from each converter, and the converter DC Two or more systems of converter AC current controllers for sending voltage control signals for controlling AC currents based on the deviation between the output of the pressure controller and the output of the AC current detecting means, and the input voltage control signal. In a start-up control device for a power converter including a control circuit having two or more pulse width modulation control means for controlling pulse width modulation of each converter based on the above, a zero voltage control signal is sent to the control circuit. Before the system is combined with the zero voltage control signal generator, the converter DC voltage controller of one of the converter systems detects the DC voltage detecting means based on the switching timing signal from the synchronous controller. The zero-voltage control signal is supplied to the first control signal switch that gives a signal based on the deviation of the DC voltage and the converter AC current controller of the remaining converter system. DC voltage control and AC voltage control are provided by providing a second control signal switch for giving a signal and a signal supplying means for giving a voltage control signal by the synchronous controller only to the pulse width modulation controlling means of the remaining converter system. The present invention is characterized in that the control is performed without interfering with the AC current control.

Further, according to a sixth aspect of the present invention, there is provided a start-up control device for a power converter in which two or more converters are connected in parallel to the commercial power supply system via a first circuit breaker and the commercial power supply system. On the other hand, one system of initial charging circuit connected in parallel via a second circuit breaker, and having a DC output side connected to a DC output side of the converter via a DC smoothing capacitor, and an AC of each converter. AC current detecting means for detecting a current, system voltage detecting means for detecting a system voltage of the commercial power supply system, AC voltage detecting means for detecting an AC voltage of the converter, and DC for detecting a DC voltage of each converter. A voltage detecting means is provided, a DC voltage reference setter that sends out a DC voltage reference set value, and a switching timing signal according to before and after system connection Before turning on, the first circuit breaker is turned off, the second circuit breaker is turned on, the DC smoothing capacitor is charged by the initial charging circuit, and the converter is operated as an inverter to generate an AC voltage. A voltage control signal for synchronously controlling the system voltage by the system voltage detection means and the AC voltage by the AC voltage detection means is transmitted, and when synchronized, the first circuit breaker is turned on, and the second circuit breaker is turned on. Based on the difference between the DC voltage detected by the DC voltage detection means and the DC voltage reference set value set by the DC voltage reference setting device, a synchronous controller for turning off the circuit breaker and inserting the system in parallel. Converter DC voltage controllers of two or more systems, each of which outputs a control signal for controlling the DC voltage output from each converter, and the converter DC Two or more systems of converter AC current controllers for sending voltage control signals for controlling AC currents based on the deviation between the output of the pressure controller and the output of the AC current detecting means, and the input voltage control signal. In a start-up control device for a power converter including a control circuit having two or more pulse width modulation control means for controlling pulse width modulation of each converter based on the above, a zero voltage control signal is sent to the control circuit. Zero voltage control signal generator, and before the system is connected to the deviation of the DC voltage detected by the DC voltage detection means in each converter DC voltage controller based on the switching timing signal from the synchronous controller Based on the first control signal switch, and a second controller for applying the zero voltage control signal to the converter AC current controller of either one of the converter systems. By providing the control signal switch and the signal supply means for supplying the voltage control signal by the synchronous controller only to the pulse width modulation control means of the converter system, without interfering the AC voltage control and the AC current control. In addition to the control configuration, each converter AC current controller is composed of a proportional calculator and an integral calculator, and after the AC voltage output by each converter becomes a constant voltage, switching from the synchronous controller is performed. A voltage control signal based on the deviation between the output of the converter DC voltage controller and the output of the AC current detecting means is output to the converter AC current controller via the second control signal switch that switches based on the timing signal. The voltage control signal is output to the proportional computing unit side, and after the AC current output from each of the converters reaches a constant value, the converter AC current control is performed on the voltage control signal. Third to output the integral calculator side
The control signal switch of the present invention is provided to control the DC voltage control and the AC voltage control and the AC current control without interfering with each other.

[0027] According to a seventh aspect of the present invention, there is provided a start-up control device for a power converter in which two or more converters are connected in parallel to the commercial power supply system via a first circuit breaker and the commercial power supply system. On the other hand, the first charging circuit is connected in parallel via the second circuit breaker, and the direct current output side is connected to the direct current output side for the single system of the converter via the direct current smoothing capacitor; AC current detection means for detecting the AC current of the converter, system voltage detection means for detecting the system voltage of the commercial power supply system, AC voltage detection means for detecting the AC voltage of the converter, the DC voltage of each converter A DC voltage reference setter for sending a DC voltage reference set value, and a switching timing signal according to before and after system integration, Before the insertion, the first circuit breaker is turned off, the second circuit breaker is turned on, the DC smoothing capacitor is charged by the initial charging circuit, and the converter is operated as an inverter to generate an AC voltage. Then, a voltage control signal for synchronously controlling the system voltage by the system voltage detection means and the AC voltage by the AC voltage detection means is transmitted, and when synchronized, the first circuit breaker is turned on and the second circuit breaker is turned on. Based on the deviation between the DC voltage detected by the DC voltage detection means and the DC voltage reference set value set by the DC voltage reference setter. And two or more systems of converter DC voltage controllers for sending control signals for controlling the DC voltages output from the converters, respectively, and Two or more systems of converter AC current controllers for sending voltage control signals for controlling AC currents based on the deviation between the output of the voltage controller and the output of the AC current detecting means, and the input voltage control signal. In a start-up control device for a power converter including a control circuit having two or more pulse width modulation control means for controlling pulse width modulation of each converter based on the above, a zero voltage control signal is sent to the control circuit. Before the system is combined with the zero voltage control signal generator, the converter DC voltage controller of one of the converter systems detects the DC voltage detecting means based on the switching timing signal from the synchronous controller. The zero-voltage control signal is supplied to the first control signal switching device which gives a signal based on the deviation of the DC voltage and the converter AC current controller of the remaining converter system. By providing a second control signal switcher for supplying the voltage control signal and a signal supply means for supplying the voltage control signal by the synchronous controller only to the pulse width modulation control means of the remaining converter system, DC voltage control and AC voltage control And the alternating current control are controlled without interfering with each other.

[0028]

In the power converter start-up control device according to the first aspect of the present invention, the control signal switch is provided to each converter AC current controller based on the switching timing signal from the synchronous controller before the system is connected. A control signal based on the zero-voltage control signal from the zero-voltage control signal generator is applied to control the AC current of each converter to zero based on the zero-voltage control signal while synchronizing with the system voltage of the commercial power supply system. The voltage is controlled to be output to the AC side of each converter.

In the start-up control device for a power converter according to a second aspect of the present invention, the converter DC is supplied via the first control signal switcher based on the switching timing signal from the synchronous controller before the system is connected. The zero voltage control signal from the zero voltage control signal generator is applied to the voltage controller, and the zero voltage control signal is applied to the converter AC current controller of either one of the converter systems via the second control signal switch. And, the AC voltage control system and the AC current control system are controlled without interfering by applying the voltage control signal by the synchronous controller only to the pulse width modulation control means of the converter system via the signal supply means. .

In the start-up control device for a power converter according to a third aspect of the present invention, the zero voltage control signal generator is provided to each converter DC voltage controller based on the switching timing signal from the synchronous controller before the grid connection. And a zero-voltage control signal from the converter AC current controller of one of the converter systems via the second control signal switch, and a pulse width modulation control means of the converter system. To the AC voltage control system without interfering with each other by giving a voltage control signal from the synchronous controller via the signal supply means to each converter, and each converter AC current controller is proportionally calculated. After the AC voltage output from each converter reaches a constant voltage, it is switched off based on the switching timing signal from the synchronous controller. A voltage control signal based on a deviation between the output of the converter DC voltage controller and the output of the AC current detecting means is output to the proportional calculator side of the converter AC current controller via the second control signal switching device to be replaced, and After the AC current output from each converter reaches a constant value, the voltage control signal is output to the integration calculator side of the converter AC current controller through the third control signal switcher to control the DC voltage. .

In the start-up control device for a power converter according to a fourth aspect of the present invention, a signal based on the deviation of the DC voltage detected by each DC voltage detecting means is transmitted via the control signal switcher before the grid connection. The voltage control signal from the synchronous controller is added to the voltage control signal output from each converter AC current controller by the addition means, and is sent to each pulse width modulation control means. As a result, an AC voltage that synchronizes with the system voltage is generated while balancing the DC voltage.

Further, in the start-up control device for the power converter according to the fifth aspect of the present invention, the converter DC voltage controller of either one of the converter systems is selected based on the switching timing signal from the synchronous controller before the system is connected. A signal based on the deviation of the DC voltage detected by each DC voltage detecting means is given through the first control signal switch, and the converter AC current controller of the remaining converter system is passed through the second control signal switch. The zero-voltage control signal from the zero-voltage control signal generator, and the voltage control signal from the synchronous controller is given to only the remaining pulse width modulation control means of the converter system via the signal supply means. The voltage control and the AC voltage control are controlled without interfering with the AC current control.

Further, in the power converter start-up control device according to a sixth aspect of the present invention, before the grid connection, each converter DC is connected via the first control signal switching device based on the switching timing signal from the synchronous controller. A signal based on the deviation of the DC voltage detected by each DC voltage detecting means is given to the voltage controller, and zero voltage control is performed to the converter AC current controller of either one of the converter systems via the second control signal switch. AC voltage control and AC current control by giving a zero voltage control signal from a signal generator and giving a voltage control signal by the synchronous controller only to the pulse width modulation control means of the converter system via the signal supply means. While controlling and without interfering with each other, each converter AC current controller is composed of a proportional calculator and an integral calculator, and the AC voltage output by each converter is Based on the deviation between the output of the converter DC voltage controller and the output of the AC current detecting means via the second control signal switcher that switches based on the switching timing signal from the synchronous controller after the constant voltage is reached. The voltage control signal is output to the proportional calculator side of the converter AC current controller, and after the AC current output from each converter reaches a constant value, the voltage control signal is converted via the third control signal switch. By outputting to the integration calculator side of the AC current controller, the DC voltage control and the AC voltage control and the AC current control are controlled without interfering with each other.

Further, in the start-up control device for the power converter according to the seventh aspect, the converter DC voltage controller of either one of the converter systems is selected based on the switching timing signal from the synchronous controller before the system is connected. A signal based on the deviation of the DC voltage detected by each DC voltage detecting means is given through the first control signal switch, and the converter AC current controller of the remaining converter system is passed through the second control signal switch. The zero voltage control signal from the zero voltage control signal generator, and by supplying the voltage control signal by the synchronous controller via the signal supply means only to the pulse width modulation control means of the remaining converter system. The voltage control and the AC voltage control are controlled without interfering with the AC current control.

[0035]

EXAMPLES Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram illustrating a startup control device for a power converter according to a first embodiment. In FIG. 1, an alphabetical character a after the numeral as a reference sign relates to the first PWM converter system, and b refers to the second PWM converter system, and these first and second PWM converter systems are collectively referred to. Reference numerals 1 to 17 and 19 to 21 indicate the same parts as in FIG. 10, 1 is a PWM converter, 2 is a converter transformer, and 3 is for connecting the PWM converter 1 to the power supply system side via the converter transformer 2. It is a circuit breaker.

Reference numeral 4 denotes an initial charging rectifier for applying a DC voltage before cooperation with the power supply system side of the PWM converter 1, reference numeral 5 denotes an initial charging transformer which forms an initial charging circuit together with the initial charging rectifier 4, and 6 denotes an initial charging circuit. At the time of charging, the initial charging rectifier 4 is connected to the power system side via the initial charging transformer 5, and after the system cooperation, the initial charging rectifier 4 is disconnected from the power system side via the initial charging transformer 5 described above. Circuit breaker for switching, 7 is PWM
It is a DC smoothing capacitor provided on the DC output side of the converter 1.

Reference numeral 8 is a DC voltage detector for detecting the DC voltage output from the PWM converter 1, 9 is an AC current detector provided between the converter transformer 2 and the circuit breaker 3,
10 is a system voltage detector for detecting the system voltage of the power supply system,
Reference numeral 11 is an AC voltage detector that detects an AC voltage generated on the system side of the converter transformer 2, 12 is a switching timing signal τ before the system is connected, and circuit breakers 3 and 6 in the main circuit and the later-described The control signal switch 23 is set to the position shown in the figure, a DC voltage is applied to the DC smoothing capacitor 7 from the initial charging circuit, the PWM converter 1 is operated as an inverter, and an AC voltage is generated on the converter transformer 2 side to generate a system voltage. The system voltage Vs detected by the detector 10 and the AC voltage Vc of the PWM converter 1 detected by the AC voltage detector 11 are input to input the system voltage Vs and the AC voltage Vc.
_Is a synchronous controller that generates a voltage control signal E _cs for synchronizing the signals. After the system is connected, the circuit breakers 3 and 6 and the control signal switch 23 in the main circuit are controlled to positions opposite to the illustrated positions based on the switching timing signal τ.

Reference numeral 13 is a DC voltage reference setting device, 14 is a subtractor for taking a difference between the DC voltage signal detected by the DC voltage detector 8 and the DC voltage reference setting signal set by the DC voltage reference setting device 15, and 15 Is a converter DC voltage controller for obtaining a converter AC current reference value for controlling the DC voltage output from the PWM converter 1 based on the output of the subtractor 14, and 16 is an AC current signal detected by the AC current detector 9. And a converter AC current reference value output from the converter DC voltage controller 15,
Reference numeral 17 is a converter AC current controller which sends a voltage control signal E _cv to a pulse width modulation control circuit 20 described later based on the output of the subtractor 16.

Reference numeral 19 is a triangular wave generator for generating a triangular wave, and 2
Reference numeral 0 denotes a pulse width modulation control circuit for performing pulse width modulation control on a voltage control signal input via an adder 23, which will be described later, by a triangular wave output from a triangular wave generator 19, and 21 a voltage control output from the synchronization controller 12. The PWM converter 1 is a proportional calculator that halves the signal, and is controlled by the gate pulse signal output from the pulse width modulation control circuit 20.

Further, as a new configuration, 22 is a zero voltage control signal generator for generating a 0 V zero voltage control signal to be applied to the DC voltage controller 15 to turn off the DC voltage control of the PWM converter 1 before the system is connected. , 23 are used to switch between the voltage control signal output from the subtractor 14 and the zero voltage control signal from the zero voltage control signal generator 22 according to the switching timing signal τ output from the synchronous control device 12 before the system is merged. A control signal switcher 24 performs addition of the voltage control signal output from the synchronous controller 12 and the voltage control signal output from the converter AC current controller 17 by halving the voltage control signal output from the proportional calculator 21. It is an adder that does.

Next, the operation of the first embodiment having the above configuration will be described. In FIG. 1, before the system is connected, the circuit breaker 3 is turned off and the circuit breaker 6 is turned on in the main circuit by the switching timing signal τ output from the synchronous controller 12, and the initial charging transformer 5 is used. Rectifier 4 for initial charging
The DC smoothing capacitor 7 is charged with a DC voltage by the PWM converter 1, and the pulse width modulation control of the DC voltage is performed by the PWM converter 1, so that the AC is applied to the converter transformer 2 side of the circuit breaker 3 via the converter transformer 2. Generating voltage.

On the other hand, in the control circuit, the synchronous controller 1
The zero-voltage control signal from the zero-voltage control signal generator 22 is output to the DC voltage controller 15 via the control signal switch 23 by the switching timing signal τ output from the control signal switch 23. Therefore, as the output of the DC voltage controller 15,
The zero voltage control signal is output, the control operation of the PWM converter 1 by the pulse width modulation control circuit 20 is not performed, and the DC voltage control is in the OFF state.

Since the input to the converter DC voltage controller 15 is a zero voltage control signal, the converter AC current reference value as an output is zero. It outputs a voltage control signal that makes the alternating current of the PWM converter 1 detected by the current detector 9 zero. Therefore, the output of the converter AC current controller 17 outputs a voltage control signal for zero control of the converter AC current.

Further, by the AC voltage detector 11, the PWM converter 1 via the converter transformers 2a and 2b.
The sum of the AC voltages generated by a and 1b is detected, and the synchronous controller 12 calculates the sum Vc of the AC voltages, the system voltage signal Vs detected by the system voltage detector 10, its frequency, phase, and A voltage control signal E _cs is generated as an output in order to perform control for synchronizing the amplitudes. Therefore, the voltage control signal E _cs output from the synchronous controller 12
Serves as a voltage control signal for synchronizing with the system voltage. However, since this voltage control signal should be generated by the PWM converter 1 as a whole, a voltage control signal that is halved by the proportional calculator 21 is required.

The voltage control signal output from the converter AC current controller 17 for zero control of the converter AC current and the voltage control signal for synchronizing with the system voltage output from the proportional calculator 21 are added together. 24, and the pulse width modulation control circuit 20 adds the triangular wave generator 19
By generating the gate pulse signal in comparison with the triangular wave output from the output, it is possible to generate an AC voltage synchronized with the system voltage while controlling the AC current flowing between the PWM converters 1a and 1b to zero.

Next, after the system is connected, the main circuit uses the switching timing signal τ output from the synchronization controller 12
The circuit breaker 3 is turned on and the circuit breaker 6 is turned off. As a result, the initial charging circuit including the initial charging rectifier 4 via the initial charging transformer 5 is disconnected from the commercial power supply system, and the PW
The M converter 1 is connected to the commercial power supply system via the converter transformer 2.

On the other hand, as the control circuit, the synchronous controller 12
The control signal switch 23 switches the output of the adder 14 to the converter DC voltage controller 15 according to the switch timing signal τ output by the converter. As a result, the difference between the DC voltage reference set value set by the DC voltage reference setter 13 and the output DC voltage of each PWM converter 1a and 1b detected by the DC voltage detector 8 is output by the subtractor 14, respectively. Therefore, DC voltage control is performed by the converter DC voltage controller 15, and each PW is controlled.
A converter AC current reference value corresponding to the deviation between the output DC voltage of the M converters 1a and 1b and the DC voltage reference set value is output.

For this reason, converter DC voltage control and AC current control are performed after the system is connected. Also,
The voltage control signal output from the proportional calculator 21 is a voltage control signal that is 1/2 the voltage control signal output from the synchronization controller 12, and is a signal synchronized with the system voltage. By doing so, it operates as feedforward compensation of the system voltage.

In the first embodiment, the output of the adder 14 is switched to the switching timing signal τ output by the synchronization controller 12.
Although it was output to the converter DC voltage controller 15 via the control signal switch 23 which is switched by the converter DC voltage controller 15, as shown in FIG.
5, the control signal switching unit 23 is provided between the converter DC voltage controller 15 and the subtractor 16, and the DC voltage control by the converter DC voltage controller 15 is switched by the control signal switching unit 23. However, there is a similar effect.

Therefore, according to the first embodiment, the DC voltage control of each of the PWM converters 1a and 1b is turned off based on the zero voltage control signal from the zero voltage control signal generator 22 before the system is combined. While controlling the AC current to zero, the voltage synchronized with the system voltage of the commercial power supply system is controlled to be output to the AC side of the PWM converters 1a and 1b. Therefore, between the two systems of PWM converters 1a and 1b. The exchange of current is eliminated, an AC voltage that is synchronized with the system voltage can be generated, and the system can be combined. Further, in the conventional configuration, there is a possibility of voltage imbalance between the systems, and it was necessary to make the element withstand voltage more than that determined by the rated value of each system. It has the effect that it can be set according to a value.

Example 2. Next, FIG. 3 is a configuration diagram illustrating a startup control device for a power converter according to a second embodiment. Figure 3
A function for controlling the AC voltage control and the AC current control of the PWM converter without interference is added to the first embodiment shown in FIG. 1, and the second P in FIG.
A control signal switch 25 for removing the adder 24b of the WM converter 1b system and switching the input to the converter AC current controller 17a of the first converter 1a to the output of either the subtractor 16a or the zero voltage control signal generator 22. Is added, and the control signal switch 25 is controlled by the synchronous controller 12A.

Here, the synchronization controller 12A causes the converter AC current controller 17a of the first converter 1a to apply the zero voltage from the zero voltage control signal generator 22 by the switching timing signal τ ₁ before the system is connected. The control signal switching device 25 is controlled so that the control signal is output, and after the system is combined, first, the switching timing signal τ ₁ outputs the control signal output from the subtracter 16a to the converter AC current controller 17a. The control signal switch 25 is controlled so that the AC current control of the first PWM converter 1a operates, and thereafter, by the switch timing signal τ ₂ output at a certain fixed timing, the subtractor 14 outputs the signal. The control signal switch 23 is controlled to output the deviation between the DC voltage and the DC voltage reference value to the converter DC voltage controller 15, and the PWM converter is controlled. So that to start the DC voltage control. In the main circuit, the circuit breaker 3 is turned off by the switching timing signal τ ₁ before the system is connected.
Circuit breaker 6 is turned on, and after the system is connected, circuit breaker 3 is turned on,
The circuit breaker 6 will be turned off.

Next, the operation will be described. In FIG. 3, before the grid connection, the circuit breaker 3 is turned off in the main circuit by the switching timing signal τ ₁ from the synchronous controller 12A.
The FF and the circuit breaker 6 are turned on, and the DC voltage is charged in the DC smoothing capacitor 7 by the initial charging rectifier 4 via the initial charging transformer 5, and this DC voltage is subjected to pulse width modulation control by the PWM converter 1. As a result, the converter transformer 2 of the circuit breaker 3 via the converter transformer 2
AC voltage is generated on the side.

By the way, the voltage control signal E _CS for synchronizing with the system voltage, which is the voltage control signal output from the synchronization controller 12A, is multiplied by ½ by the proportional calculator 21 and halved. The voltage control signal is added to the adder 24a.
As a result, it is input only to the control system of the first PWM converter 1a. On the other hand, the zero timing control signal from the zero voltage control signal generator 22 is output to the converter AC current controller 17a of the first PWM converter 1a by the switching timing signal τ ₁ output from the synchronization controller 12A, Zero is output as the output of the converter AC current controller 17a of the first PWM converter 1a. Therefore, the AC current control of the first PWM converter 1a is not performed.

Here, the voltage control signal output from the proportional calculator 21 causes only the first PWM converter 1a to generate an AC voltage, but if the second PWM converter 1b does not generate an AC voltage, An alternating current flows between the PWM converters 1a and 1b via the converter transformer 2. Second, to make this alternating current zero
PWM converter 1b converter AC current controller 1
7b outputs a voltage control signal, and as a result, the first
By generating an AC voltage similar to that of the PWM converter 1a, it is possible to generate an AC voltage synchronized with the system voltage while controlling the AC current flowing between the PWM converters 1a and 1b to zero, and at the same time, to generate the AC voltage. Control is
Since the first PWM converter 1a and the alternating current control are controlled by the second PWM converter 1b, respectively, the alternating voltage control and the alternating current control of the PWM converters 1a and 1b are controlled without interfering with each other. be able to.

After the system is connected, first, the control signal switching unit 25 outputs the control signal output from the subtracter 16a to the converter AC current controller 17a according to the switching timing signal τ ₁ output from the synchronous controller 12A. As a result, the alternating current control of the first PWM converter 1a comes into operation. After that, the control signal switch 23 is operated by the switching timing signal τ ₂ output from the synchronous controller 12A at a certain fixed timing, and the deviation between the detected DC voltage and the DC voltage reference set value is controlled by the subtracter 14 as described above. The signal is output to the converter DC voltage controller 15 via the signal switch 23, and DC voltage control of the PWM converters 1a and 1b is started. At this time, in the main circuit, the circuit breaker 3 is turned on and the circuit breaker 6 is turned off by the switching timing signal τ ₁ .

Therefore, according to the second embodiment, before the system insertion, the signal based on the voltage control signal output from the synchronous controller 12A is added to the zero voltage control signal from the zero voltage control signal generator 22. The signal added by 24a is used as the first PW
The AC voltage control is performed by inputting only to the control system of the M converter 1a, and the AC current control of the first PWM converter 1a is not performed. At that time, the converter transformer 2
An alternating current flows between the PWM converters 1a and 1b via the converter so that the alternating current becomes zero so that the converter alternating current controller 17 of the second PWM converter 1b
By outputting a voltage control signal by b, as a result, an AC voltage similar to that of the first PWM converter 1a is generated, and the AC current flowing between the PWM converters 1a and 1b is controlled to zero. By generating an AC voltage that is synchronized with the system voltage, AC voltage control
Since the first PWM converter 1a is controlled by the second PWM converter 1b and the alternating current control is controlled by the second PWM converter 1b, the PWM converters 1a and 1b are controlled.
There is an effect that the AC voltage control and the AC current control can be controlled without interfering with each other. Further, in the conventional configuration, there is a possibility of voltage imbalance between the systems, and it was necessary to make the element withstand voltage more than that determined by the rated value of each system. It has the effect that it can be set according to a value.

Example 3. Next, FIG. 4 is a configuration diagram illustrating a startup control device for a power converter according to a third embodiment. Figure 4
A function for improving the controllability of the converter AC current control is added to the second embodiment shown in FIG. 3, and the converter AC current controller 17 in FIG.
It is replaced with a converter AC current controller 17A composed of a proportional calculator and an integral calculator, and this converter AC current controller 17A is a proportional calculator 17a ₁ and an integral calculator 17a _{2 of} the first PWM converter 1a system. , The second PW
The M converter 1b system includes a proportional calculator 17b ₁ and an integral controller 17b ₂ .

Further, a control signal switch 26 for switching the input signal of the integration calculator 17a ₂ of the first PWM converter 1a is added, and the control signal switches 23, 25, 26 are
The switching is controlled based on the switching timing signal from the synchronization controller 12B.

Next, the operation will be described. In FIG. 4, before the system is combined, first, in the main circuit, the circuit breaker 3 is turned off and the circuit breaker 6 is turned on by the switching timing signal τ ₀ from the synchronous controller 12B to turn on the initial charging transformer 5. The DC smoothing capacitor 7 is charged with a DC voltage by the rectifier 4 for initial charging via the
By performing pulse width modulation control by the M converter 1, an AC voltage is generated on the converter transformer 2 side of the circuit breaker 3 via the converter transformer 2, and the control signal switching units 23, 25, 26 are also provided. Is controlled to the position shown in the figure based on the switching timing signals τ ₁ , τ ₂ , τ ₃ from the synchronous controller 12B, and switching is performed so as to output the zero voltage control signal from the zero voltage control signal generator 22. . In this state, the same control as that before the system insertion in the second embodiment shown in FIG. 3 is performed, and AC voltage control is performed for the first converter 1a and AC current control is performed for the second converter 1b. It is being appreciated.

The switching timing signal τ ₁ output from the synchronous controller 12B at the timing when the AC voltage output from the PWM converters 1a and 1b becomes a constant voltage.
Causes the control signal switch 25 to switch, and the subtractor 16a
The deviation between the AC current of the first PWM converter 1a and the AC current reference value output by the above is output to the proportional calculator 17a ₁ . Here, when the integral calculator 17a ₂ is also operated, the interference in the alternating current control of the PWM converter 1a and 1b occurs, integral calculator 17a to _2, the control signal switching device 26 by the zero voltage control signal generator 22 The zero voltage control signal from is applied to prevent the integral control from operating.

In such a state, the switching timing signal τ ₀ output from the synchronization controller 12B turns on the circuit breaker 3 of the main circuit and turns off the circuit breaker 6, so that the system is connected. At this time, in the control circuit, if the proportional calculator 17a ₁ is not operated, the first P
Since the AC current of the WM converter 1a is not controlled and there is a possibility of input overcurrent, the proportional calculator 17a ₁ needs to be continuously operated.

Next, the control signal switch 26 is switched by the switching timing signal τ ₂ output from the synchronous controller 12B at a timing when the AC currents of the PWM converters 1a and 1b are stabilized at a certain value, and the control signal is switched. The integration calculator 17a ₂ operates by outputting the output of the calculator 25.

Thereafter, at a certain fixed timing, the control signal switching unit 23 is switched by the switching timing signal τ ₃ output from the synchronous controller 12B, and the PWM converter DC voltage output from the subtractor 14 and the DC voltage reference value are output. The deviation of is output to the converter DC voltage controller 15 to operate the DC voltage control. By a series of these operations, it is possible to generate an AC voltage that is synchronized with the system voltage while controlling the AC current flowing between the PWM converters 1a and 1b to zero, and improve the controllability of the AC current control. it can.

Therefore, according to the third embodiment, before the system insertion, the converter DC voltage controllers 15a and 15b are supplied from the zero voltage control signal generator 22 based on the switching timing signal from the synchronous controller 12B. A zero voltage control signal is supplied, a zero voltage control signal is supplied to the converter AC current controller 17a of one converter system via the second control signal switching device 25, and the pulse width modulation control means 20 of the converter system is supplied. A voltage control signal from the synchronous controller 12B is given only via the adder 24a, and each converter AC current controller 17a and 17b is composed of a proportional calculator and an integral calculator so that the AC voltage output by each converter is After the constant voltage is reached, the second control signal switch 25 that switches based on the switching timing signal from the synchronous controller 12B is used. Converter DC voltage controller 15 and
Of a voltage control signal based on the deviation between the output of the AC current detector and the outputs of the AC current detectors 9a and 9b.
Output to the proportional calculator side of the converter, and after the AC current output by each converter reaches a constant value, the voltage control signal is set to the third value.
By outputting to the integration calculator side of the converter AC current controller via the control signal switch 26, the DC voltage control and the AC voltage control system can be controlled without interfering with the AC current control system. PWM converters 1a and 1
There is no exchange of electric current with b, an AC voltage that is synchronized with the system voltage can be generated, and the system can be combined. Further, in the conventional configuration, there is a possibility of voltage imbalance between the systems, and it was necessary to make the element withstand voltage more than that determined by the rated value of each system. It has the effect that it can be set according to a value.

Example 4. Next, FIG. 5 is a configuration diagram illustrating a startup control device for a power converter according to a fourth embodiment. Figure 5
A DC voltage control function is added to eliminate the imbalance of DC voltage before system integration, and when the DC voltage output by the initial charging rectifier 4 is applied to the PWM converters 1a and 1b collectively, the PWM converter Although the initial charging circuit is not overloaded by the alternating current flowing between 1a and 1b, the initial charging DC voltage of the PWM converters 1a and 1b may be unbalanced due to the alternating current flowing. To eliminate.

In FIG. 5, the same parts as those of the embodiment shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted. In FIG. 5, the initial charging transformers 5a and 5b and the initial charging rectifiers 4a and 4b in FIG. 1 are replaced with an initial charging circuit including one circuit of the initial charging transformer 5 and the initial charging rectifier 4, and the PWM The converters 1a and 1b are collectively connected to the DC circuit side.

Further, in the control circuit, the control signal switch 23 for switching the control signal input to the converter DC voltage controller 15 is eliminated, and the DC voltage of the first PWM converter 1a detected by the DC voltage detector 8a is eliminated. An adder 27 for obtaining the sum of the voltage value and the DC voltage value of the second PWM converter 1b detected by the DC voltage detector 8b, and a proportional operation for halving the DC voltage value output from the adder 27. And a subtracter 1 for the output of the proportional calculator 28 and the DC voltage reference set value output from the DC voltage reference setter 13.
4 is added to the control signal switching unit 29 for switching the input to 4 by the switching timing signal τ output from the synchronization controller 12.

Next, the operation will be described. In FIG. 5, the circuit breaker 3 is OF in the main circuit due to the switching timing signal τ from the synchronous controller 12 before the system is combined.
F, the circuit breaker 6 is turned on, and the DC voltage is charged in the DC smoothing capacitor 7 by the initial charging rectifier 4 through the initial charging transformer 5 and the PWM converter 1 controls the pulse width modulation of the DC voltage. As a result, an AC voltage is generated on the converter transformer 2 side of the circuit breaker 3 via the converter transformer 2, and the control signal switch 2
Reference numeral 9 outputs a voltage control signal output from the proportional calculator 28.

In this case, in the control circuit, the sum of the DC voltage values output from the adder 27 is 1 /
Since twice the voltage control signal V _ds is outputted from the subtractor 14 is detected from the voltage control signal V _ds inputted through the control signal switching device 29 the DC voltage detector 8a and 8b PWM The deviation from the DC voltage of the converters 1a and 1b is output. The deviations are input to the converter DC voltage controller 15, and the AC current reference value for controlling the DC voltage is output. Therefore, PW
DC voltage control is performed in the M converters 1a and 1b.

This AC current reference value and AC current detector 9a
And 1b detected by PWM converters 1a and 1b
Difference from the AC current is output by the subtractor 16 and PW
The M converter AC current controller 17 outputs a voltage control signal corresponding to the difference. And
The voltage control signal E _CS from the synchronous controller 12 is added by the adder 24 to the voltage control signal output from each PWM converter AC current controller 17 and sent to each pulse width modulation control circuit 20a and 20b. Therefore, since the DC voltage control and the AC current control are performed in the PWM converters 1a and 1b,
It is possible to generate an AC voltage that is synchronized with the system voltage while balancing the DC voltage.

Therefore, according to the fourth embodiment, when the DC voltage output from the initial charging rectifier 4 is applied to the PWM converters 1a and 1b all at once, the PWM converters 1a and 1b are driven by an alternating current. Even when there is a possibility that the initial charging DC voltages of 1a and 1b are unbalanced, a signal based on the deviation of the DC voltages detected by the DC voltage detectors 8a and 8b is output via the control signal switch 29. Converter DC voltage controller 15a
15b and 15b, and the voltage control signals from the synchronous controller 12 are added by the adders 24a and 24b to the voltage control signals output from the converter AC current controllers 17a and 17b, respectively.
Since it is sent to a and 20b, there is an effect that an AC voltage that is synchronized with the system voltage can be generated while balancing the DC voltage. Further, in the conventional configuration, there is a possibility of voltage imbalance between the systems, and it was necessary to make the element withstand voltage higher than that determined by the rated value of each system. It has the effect that it can be set according to a value.

Example 5. Next, FIG. 6 is a configuration diagram showing a startup control device for a power converter according to a fifth embodiment. Figure 6
A control function which does not interfere with the AC voltage control and the AC current control of the PWM converters 1a and 1b is added to the fourth embodiment shown in FIG. 5, and in FIG. The adder 24b on the converter side is eliminated, and as in the second embodiment, the zero voltage control signal generator 22 for generating the zero voltage control signal and the input to the converter AC current controller 17a of the first converter 1a are subtracted from each other. 16a or a control signal switch 25 for switching to the output of the zero voltage control signal generator 22 is added, and the control signal switch 25 is controlled by the synchronous controller 12, and the first converter is also used. The DC voltage reference of 1a is not switched by the control signal switch 29, and only the DC voltage reference set value output by the DC voltage reference setter 13 is reduced on the first converter 1a side. And to output the vessel 14a.

Next, the operation will be described. In FIG. 6, the circuit breaker 3 is OF in the main circuit due to the switching timing signal τ from the synchronous controller 12 before the system is combined.
F, the circuit breaker 6 is turned on, and the DC voltage is charged in the DC smoothing capacitor 7 by the initial charging rectifier 4 via the initial charging transformer 5 and this DC voltage is subjected to pulse width modulation control by the PWM converter 1. As a result, an AC voltage is generated on the converter transformer 2 side of the circuit breaker 3 via the converter transformer 2, and in the control circuit, the control signal switching device 25 causes the zero voltage control signal generator 22 to operate. , And the control signal switch 29 outputs the voltage control signal V _ds output by the proportional calculator 28.

In this case, the converter AC current controller 17a on the first PWM converter 1a side receives the zero-voltage control signal output from the control signal switch 25, so that the output is zero. The adder 24a adds the AC voltage control signal output from the proportional calculator 21. Therefore, the first PWM converter 1a is only performing AC voltage control.

On the other hand, in the second PWM converter 1b,
Since the voltage control signal V _ds obtained by multiplying the sum of the DC voltage values output from the adder 27 by the proportional calculator 28 is output, the subtractor 14 on the second PWM converter 1 b side is output.
From b, the deviation between the voltage control signal V _ds input through the control signal switch 29 and the DC voltage of the second PWM converter detected by the DC voltage detector 8 b on the second PWM converter 1 b side is shown. Will be output. This deviation is input to the converter DC voltage controller 15b on the side of the second PWM converter 1b, and the converter DC voltage controller 15b outputs a converter AC current reference value for controlling the converter DC voltage. Therefore, the second PW
In the M converter 1b, DC voltage control is being performed.

This converter AC current reference value and the second PWM converter 1b detected by the AC current detector 9b
The difference from the AC current is output by the subtractor 16b, and the voltage converter signal corresponding to the difference is output by the second converter AC current controller 17b. Therefore, in the second PWM converter 1b, DC voltage control and AC current control are being performed. That is, since the first PWM converter 1a performs AC voltage control and the second PWM converter 1b performs DC voltage control and AC current control, an AC voltage that is synchronized with the system voltage while balancing the DC voltage Can be generated, and the control can be performed without interfering with each other.

Therefore, according to the fifth embodiment, the converter DC voltage controller 1 of one converter system is based on the switching timing signal from the synchronous controller 12 before the system is combined.
5b is given a signal based on the deviation of the DC voltage detected by each of the DC voltage detectors 8a and 8b via the first control signal switch 29, and the second converter AC current controller 17a of the remaining converter system is provided with the second signal. Control signal switch 25
The zero voltage control signal from the zero voltage control signal generator 22 is given via the control circuit, and the voltage control signal by the synchronous controller 12 is given only to the remaining pulse width modulation control circuit 20a of the converter system by the adder 24a. Because I chose
Not only can an AC voltage that is synchronized with the system voltage be generated while balancing the DC voltage, but DC voltage control and AC voltage control can also be controlled without interfering with each other, and mutual control interference can be prevented. The effect is that it can be controlled without it. Also, in the conventional configuration,
There is a possibility of voltage imbalance between the systems, and it was necessary to make the element withstand voltage more than that determined by the rated value of each system, but in the above-mentioned embodiment, it is possible to set according to the rated value of each system. Has the effect.

Example 6. Next, FIG. 7 is a configuration diagram illustrating a startup control device for a power converter according to a sixth embodiment. Figure 7
A function for improving the controllability of the converter AC current control is added to the fifth embodiment shown in FIG. 6, and the converter AC current controller 17 in FIG. , A converter AC current controller 17A composed of a proportional calculator and an integral calculator, and this converter AC current controller 17A has a first P
WM converter 1a system of the proportional calculator 17a ₁ and integral calculator 17a _2, includes a proportional calculator 17b ₁ of the second PWM converter 1b system the integral calculator 17b _2.

Further, a control signal switch 26 for switching the input signal of the integration calculator 17a ₂ of the first PWM converter 1a is added, and the control signal switches 25, 26 and 29 are
The switching is controlled based on the switching timing signal from the synchronization controller 12B.

Next, the operation will be described. In FIG. 7, before the system is combined, first, in the main circuit, the circuit breaker 3 is turned off and the circuit breaker 6 is turned on by the switching timing signal τ ₀ from the synchronous controller 12B to turn on the initial charging transformer 5. The DC smoothing capacitor 7 is charged with a DC voltage by the rectifier 4 for initial charging via the
By performing pulse width modulation control by the M converter 1, an AC voltage is generated on the converter transformer 2 side of the circuit breaker 3 via the converter transformer 2, and in the control circuit, a control signal switch 25 is used. , 26, 29 are switching timing signals τ ₁ , τ ₂ , τ ₃ from the synchronization controller 12B.
The control signal switch 25 is controlled to the position shown in FIG.
Reference numeral 26 switches to output the zero voltage control signal from the zero voltage control signal generator 22, and control signal switch 29 switches to output the output of the comparison calculator 28. In this state, the same control as that before the system connection in FIG. 6 is performed, and the AC voltage control is performed on the first converter 1a by the second control.
The converter 1b is subjected to DC voltage control and AC current control.

Then, at the timing when the AC voltage output from the PWM converters 1a and 1b becomes a constant voltage, the control signal switch 25 is switched by the switch timing signal τ ₁ output from the synchronous controller 12B, and the subtractor 16a. The deviation between the AC current of the first PWM converter 1a and the AC current reference value output by the above is output to the proportional calculator 17a ₁ . Here, if the integration calculator 17a ₂ is also operated, interference occurs in the AC current control of the PWM converters 1a and 1b. Therefore, the control signal switch 26 supplies the zero voltage control signal from the zero voltage control signal generator 22. The integral control is not operated.

In such a state, the switching timing signal τ ₀ output from the synchronization controller 12B turns on the circuit breaker 3 of the main circuit and turns off the circuit breaker 6, so that the systems are connected together. At this time, the proportional calculator 17a ₁
If is not operated, it means that the AC current of the first PWM converter 1a is not controlled, and there is a possibility of input overcurrent. Therefore, it is necessary to operate the proportional calculator 17a ₁ .

Next, by the switching timing signal τ ₂ output from the synchronous controller 12B at a timing when the alternating currents of the PWM converters 1a and 1b are stabilized at a certain constant value,
When the control signal switch 26 switches and outputs the output of the control signal switch 25, the integration calculator 17a ₂ operates.

After that, at a certain fixed timing, the control signal switch 29 is switched by the switching timing signal τ ₃ output from the synchronous controller 12B, and the PWM converter DC voltage output from the subtractor 14 and the DC voltage reference setting. By outputting the deviation from the DC voltage reference set value set by the converter 13 to the converter DC voltage controller 15,
Operate DC voltage control. By these series of operations,
Before the system is combined, the AC current flowing between the PWM converters 1a and 1b can be controlled to a value corresponding to the unbalanced portion of the DC voltage, and an AC voltage synchronized with the system voltage can be generated. The controllability of AC current control can be improved.

Therefore, according to the sixth embodiment, before the system is combined, each converter DC voltage controller 15a and the converter DC voltage controller 15a via the first control signal switch 29 based on the switching timing signal from the synchronous controller 12B. Each DC voltage detector 8 on 15b
A signal based on the deviation of the DC voltage detected by a and 8b is given, and the converter AC current controller 17a of one converter system is supplied from the zero voltage control signal generator 22 via the second control signal switch 25. A pulse width modulation control circuit 20 for providing a zero voltage control signal and for the converter system thereof
The voltage control signal E _CS from the synchronous controller 12B is given only to a by the adder 24a, and each converter AC current controller 17a and 17b is composed of a proportional calculator and an integral calculator, and the AC output by each converter. The second control signal switching device 2 that switches based on the switching timing signal from the synchronous controller 12B after the voltage becomes a constant voltage.
A proportional control unit 17a of the converter AC current controller 17a outputs a voltage control signal based on the deviation between the output of the converter DC voltage controller 15a and the output of the AC current detector 9a.
_After the alternating current output from each converter has a constant value, the voltage control signal is output via the third control signal switch 26 to the proportional integrator 17a ₂ side of the converter alternating current controller. Since the output voltage is output to the DC voltage, it is possible not only to generate an AC voltage that is synchronized with the system voltage while balancing the DC voltage, but also to control the DC voltage control and AC voltage control without interfering with the AC current control. The effect that the controls can be performed without interfering with each other. Further, in the conventional configuration, there is a possibility of voltage imbalance between the systems, and it was necessary to make the element withstand voltage higher than that determined by the rated value of each system. It has the effect that it can be set according to a value.

Example 7. Next, FIG. 8 is a configuration diagram illustrating a startup control device for a power converter according to a seventh embodiment. Figure 8
With the addition of the DC voltage control function to eliminate the overload of the initial charging circuit and the imbalance of DC voltage before system integration,
The DC voltage output from the initial charging circuit including the initial charging rectifier 4 and the initial charging transformer 5 is converted into the PWM converter 1
When applied to only one system of a and 1b, there is a possibility that it will rise above the DC voltage specified value of the PWM converter that does not apply the DC voltage, and as a result, the initial charging is performed by the AC current flowing between the PWM converters 1a and 1b. Not only there is a possibility that the circuit will be overloaded, but there is a possibility that an imbalance will occur in the DC voltage for initial charging of the PWM converters 1a and 1b due to the flow of an alternating current, which is solved.

In FIG. 8, those parts which are the same as those of the fifth embodiment shown in FIG. 6 are designated by the same reference numerals, and a description thereof will be omitted. This Figure 8
Then, the initial charging transformer 5 and the initial charging rectifier 4 in FIG. 6 are connected to the PWM converter of only one arbitrary system of the PWM converter 1, that is, the DC circuit side of the PWM converter 1a, and in the control circuit, , P
The adder 27 for adding the DC voltage of the WM converter and the proportional calculator 28 for halving the sum of the DC voltage values are eliminated, and the DC voltage value of the first converter 1a is input to the control signal switch 29. I am trying.

Next, the operation will be described. In FIG. 8, the circuit breaker 3 is turned off in the main circuit based on the switching timing signal τ from the synchronous controller 12 before the system is combined.
The FF and the circuit breaker 6 are turned on, and the DC voltage is charged in the DC smoothing capacitor 7 by the initial charging rectifier 4 via the initial charging transformer 5, and this DC voltage is subjected to pulse width modulation control by the PWM converter 1. As a result, the converter transformer 2 of the circuit breaker 3 via the converter transformer 2
AC voltage is generated on the side, and in the control circuit, the control signal switching device 25 controls the zero voltage control signal generator 22.
Output a zero voltage control signal from the control signal switch 29
Outputs the DC voltage value of the first PWM converter 1a.

In this case, the converter AC current controller 17a of the first converter 1a receives the zero-voltage control signal output from the control signal switch 25, so that the output is zero, and the addition is performed. The proportional calculator 2 by the calculator 24a
The AC voltage control signal which is the output of 1 is added. Therefore, the first PWM converter 1a is only performing AC voltage control.

On the other hand, in the second PWM converter 1b,
Since the control signal switch 29 outputs the DC voltage value of the first PWM converter 1a, the subtractor 14b of the second PWM converter 1b includes the first PWM converter 1a.
The deviation between the DC voltage value of a and the DC voltage of the second PWM converter 1b detected by the DC voltage detector 8b is output. This deviation is input to the converter DC voltage controller 15b of the second PWM converter 1b, and the AC current reference value of the second PWM converter 1b is output. Therefore, in the second PWM converter 1b,
This means that DC voltage control is being performed.

The difference between this AC current reference value and the AC current detected by the AC current detector 9b of the second PWM converter 1b is output by the subtractor 16b, and the second PWM
The converter AC current controller 17b of the converter 1b outputs a voltage control signal corresponding to the difference. Therefore, in the second PWM converter 1b, DC voltage control and AC current control are being performed.

That is, AC voltage control is performed in the first PWM converter 1a, and the second PWM converter 1a is controlled.
Since the DC voltage control and the AC current control are performed in b, it is possible to use the initial charging circuit in the rated state and generate the AC voltage that is synchronized with the system voltage while balancing the DC voltage. It can be controlled by eliminating the mutual interference of.

Therefore, according to the seventh embodiment, the initial charging circuit for supplying the initial DC voltage to any one of the DC circuits of the PWM converter is provided before the two or more PWM converters are combined. In that case,
Based on the switching timing signal from the synchronous controller 12, the converter DC voltage controller 15b of one converter system is connected to each DC voltage detector 8 via the first control signal switch 29.
A signal based on the deviation of the DC voltage detected by a and 8b is given and the converter AC current controller 17a of the remaining converter system is supplied from the zero voltage control signal generator 22 via the second control signal switch 25. Since the zero voltage control signal is given and the voltage control signal E _CS from the synchronous controller 12 is given only to the remaining pulse width modulation control circuit 20a of the converter system by the adder 24a, it is outputted by the initial charging circuit. DC voltage is converted to PWM converter 1a
And 1b, if applied to only one system, there is a possibility that the voltage will rise above the DC voltage specified value of the PWM converter that does not apply the DC voltage.
Not only may the initial charging circuit be overloaded by the alternating current flowing between a and 1b, but there is also the possibility that an imbalance will occur in the initial charging DC voltage of the PWM converters 1a and 1b due to the alternating current flowing. However, there is an effect that these can be eliminated and the DC voltage control and the AC voltage control and the AC current control can be controlled without interfering with each other. Further, in the conventional configuration, there is a possibility of voltage imbalance between the systems, and it was necessary to make the element withstand voltage higher than that determined by the rated value of each system. It has the effect that it can be set according to a value.

As described above, the present invention is summarized as follows. According to the first to third embodiments, in the initial startup control of the PWM converters of two or more systems, the initial charging circuits that supply the initial DC voltage to the DC circuits of the PWM converters are respectively provided, and the converters are provided on the AC side of the PWM converters. Since the current controller for controlling the alternating current flowing through the transformer and the controller for controlling the alternating voltage of the PWM converter synchronized with the voltage of the commercial power system are provided, the alternating current flowing between the PWM converters is reduced to zero. It is possible to generate an AC voltage that is synchronized with the system voltage while controlling. In addition, since there is no possibility of voltage imbalance between systems, it is not necessary to make the element breakdown voltage higher than that determined by the rated value of each system, and it is possible to set according to the rated value of each system. Have.

Further, according to the fourth to sixth embodiments, each PW is provided before two or more systems of PWM converters are combined.
An initial charging circuit that supplies an initial DC voltage to the DC circuit of the M converter is collectively provided, and a DC voltage of each PWM converter and a current controller that controls the current flowing through each converter transformer on the AC side of each PWM converter are provided. Since the voltage controller for controlling and the controller for controlling the AC voltage of the PWM converter synchronized with the voltage of the commercial power system are provided, it is possible to generate the AC voltage in synchronization with the system voltage while balancing the DC voltage. it can. In addition, since there is no possibility of voltage imbalance between systems, it is not necessary to make the element breakdown voltage higher than that determined by the rated value of each system, and it is possible to set according to the rated value of each system. Have.

Further, according to the seventh embodiment, an initial charging circuit for supplying an initial DC voltage to any one of the DC circuits of the PWM converter is provided before the two or more systems of PWM converters are connected to each other. A current controller that controls the current that flows through each converter transformer on the AC side of the PWM converter, and a voltage controller that controls the DC voltage of each PWM converter except one system that supplies the initial charging DC voltage and a commercial power supply system Since a controller for controlling the AC voltage of the PWM converter synchronized with the voltage of
It is possible to generate an AC voltage that opposes the system voltage while balancing the DC voltage. In addition, since there is no possibility of occurrence of voltage imbalance between systems, it is not necessary to make the element breakdown voltage higher than that determined by the rated value of each system.
It has an effect that it can be set according to the rated value of each system.

[0098]

As described above, according to claim 1 of the present invention, before the system is combined, each converter AC current controller is provided with a control signal switching device based on the switching timing signal from the synchronous controller. A control signal based on the zero-voltage control signal from the zero-voltage control signal generator is applied to control the AC current of each converter to zero based on the zero-voltage control signal while controlling the voltage synchronized with the system voltage of the commercial power supply system. Is controlled so as to be output to the AC side of each converter, current is not exchanged between the PWM converters 1a and 1b of the two systems, an AC voltage that is synchronized with the system voltage can be generated, and the system can be used together. There is an effect that can be.
In addition, since there is no possibility of voltage imbalance between systems, it is not necessary to make the element breakdown voltage higher than that determined by the rated value of each system, and it is possible to set according to the rated value of each system. Have.

According to claim 2, before the system is combined,
Based on the switching timing signal from the synchronous controller, the zero voltage control signal from the zero voltage control signal generator is given to each converter DC voltage controller via the first control signal switch, and at least one converter system To the converter AC current controller via the second control signal switch, and voltage control by the synchronous controller via the signal supply means only to the pulse width modulation control means of the converter system. Since the signal is applied, the AC voltage flowing between the converters can be controlled to zero while generating the AC voltage synchronized with the system voltage, and the AC voltage control and the AC current control between the PWM converters can be interfered with each other. There is an effect that it can be controlled without. In addition, since there is no possibility of voltage imbalance between systems, it is not necessary to make the element breakdown voltage higher than that determined by the rated value of each system, and it is possible to set according to the rated value of each system. Have.

Further, according to claim 3, before the system is combined,
The zero voltage control signal from the zero voltage control signal generator is given to each converter DC voltage controller based on the switching timing signal from the synchronous controller, and the converter AC current controller of either one of the converter systems receives the second voltage. By providing a zero voltage control signal through the control signal switch and by supplying the voltage control signal by the synchronous controller through the signal supply means only to the pulse width modulation control means of the converter system, an AC voltage control system is provided. While controlling without interfering with the AC current control system, each converter AC current controller is composed of a proportional calculator and an integral calculator, and after the AC voltage output by each converter becomes a constant voltage, The output of the converter DC voltage controller and the AC current detection are performed through the second control signal switching device that switches based on the switching timing signal from the synchronous controller. The voltage control signal based on the deviation from the output of the means is output to the proportional calculator side of the converter AC current controller, and after the AC current output by each converter becomes a constant value, the voltage control signal is set to the third value. Since the DC voltage control is performed by outputting to the integration calculator side of the converter AC current controller via the control signal switcher, it is possible to interfere the DC voltage control and the AC voltage control system with the AC current control system. There is an effect that control can be performed without the need for current exchange between the two systems of PWM converters, an AC voltage synchronized with the system voltage can be generated, and the system can be combined. In addition, since there is no possibility of occurrence of voltage imbalance between systems, it is not necessary to make the element breakdown voltage higher than that determined by the rated value of each system.
It has an effect that it can be set according to the rated value of each system.

According to claim 4, more than two systems of P
When the initial charging circuits for supplying the initial DC voltage to the DC circuits of the PWM converters are collectively provided before the WM converter system is combined, the DC voltage detected by each DC voltage detection unit before the system combination is performed. The signal based on the deviation of is given to each converter DC voltage controller through the control signal switch, and the voltage control signal from the synchronous controller is added to the voltage control signal output from each converter AC current controller by the addition means. Since they are added to each other and sent to each pulse width modulation control means, it is possible to generate an AC voltage that is synchronized with the system voltage while balancing the DC voltage. In addition, since there is no possibility of voltage imbalance between systems, it is not necessary to make the element breakdown voltage higher than that determined by the rated value of each system, and it is possible to set according to the rated value of each system. Have.

Further, according to claim 5, P of two or more systems is used.
When the initial charging circuit that supplies the initial DC voltage to the DC circuits of the respective PWM converters is collectively provided before the WM converter system is combined, before the system combination is performed, based on the switching timing signal from the synchronous controller. A signal based on the deviation of the DC voltage detected by each DC voltage detecting means is given to the converter DC voltage controller of either one of the converter systems via the first control signal switching device, and the converter AC of the remaining converter system is supplied. The zero voltage control signal from the zero voltage control signal generator is applied to the current controller via the second control signal switch, and only the pulse width modulation control means of the remaining converter system is supplied via the signal supply means. Since the voltage control signal from the synchronous controller is applied, it is possible to generate an AC voltage that synchronizes with the system voltage while balancing the DC voltage. Not can be controlled without interfering with the AC current control with DC voltage control and AC voltage control,
It is possible to perform the control without interfering with each other. In addition, since there is no possibility of voltage imbalance between systems, it is not necessary to make the element breakdown voltage higher than that determined by the rated value of each system, and it is possible to set according to the rated value of each system. Have.

According to claim 6, P of two or more lines is used.
When the initial charging circuit that supplies the initial DC voltage to the DC circuits of the respective PWM converters is collectively provided before the WM converter system is combined, before the system combination is performed, based on the switching timing signal from the synchronous controller. A signal based on the deviation of the DC voltage detected by each DC voltage detecting means is given to each converter DC voltage controller via the first control signal switch, and at the same time, the converter AC current controller of either one of the converter systems is supplied. The zero voltage control signal from the zero voltage control signal generator is given via the second control signal switch, and the voltage control by the synchronous controller is provided only to the pulse width modulation control means of the converter system via the signal supply means. By giving a signal, AC voltage control and AC current control can be controlled without interfering with each other, and each converter AC current controller can be used as a proportional calculator. The converter DC voltage via the second control signal switching device, which is composed of a minute calculator and switches based on the switching timing signal from the synchronous controller after the AC voltage output from each converter becomes a constant voltage. After the voltage control signal based on the deviation between the output of the controller and the output of the alternating current detection means is output to the proportional calculator side of the converter alternating current controller, and the alternating current output by each converter becomes a constant value, Since the voltage control signal is output to the integration calculator side of the converter AC current controller through the third control signal switch, it is possible to generate an AC voltage that is synchronized with the system voltage while balancing the DC voltage. In addition, it is possible to control the DC voltage control and the AC voltage control without interfering with the AC current control, and it is possible to control without interfering with each other. The effect say. In addition, since there is no possibility of voltage imbalance between systems, it is not necessary to make the element breakdown voltage higher than that determined by the rated value of each system, and it is possible to set according to the rated value of each system. Have.

Therefore, according to the seventh embodiment, the initial charging circuit for supplying the initial DC voltage to any one of the DC circuits of the PWM converter is provided before the two or more PWM converters are combined. In that case,
A signal based on the deviation of the DC voltage detected by each DC voltage detecting means via the first control signal switch to the converter DC voltage controller of one of the converter systems based on the switching timing signal from the synchronous controller. And a zero-voltage control signal from the zero-voltage control signal generator to the converter AC current controller of the remaining converter system via the second control signal switch, and the pulse width modulation of the remaining converter system. Since the voltage control signal by the synchronous controller is given only to the control means through the signal supply means, the DC voltage output from the initial charging circuit is PWM.
When applied to only one of the converters, the DC voltage may rise above the DC voltage specified value of the PWM converter that does not apply the DC voltage. In addition, there is a possibility that the initial charging DC voltage between the PWM converters may become unbalanced due to the flow of AC current. However, these problems are eliminated, and DC voltage control and AC voltage control and AC current It is possible to perform control without interfering with control. Also,
Since there is no possibility of occurrence of voltage imbalance between the systems, it is not necessary to make the element breakdown voltage higher than that determined by the rated value of each system, and it is possible to set according to the rated value of each system.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a startup control device for a power converter according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram showing a start-up control device for a power converter according to a modification of the first embodiment.

FIG. 3 is a configuration diagram showing a startup control device for a power converter according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram showing a startup control device for a power converter according to a third embodiment of the present invention.

FIG. 5 is a configuration diagram showing a startup control device for a power converter according to a fourth embodiment of the present invention.

FIG. 6 is a configuration diagram showing a startup control device for a power converter according to a fifth embodiment of the present invention.

FIG. 7 is a configuration diagram showing a startup control device for a power converter according to a sixth embodiment of the present invention.

FIG. 8 is a configuration diagram showing a startup control device for a power converter according to a seventh embodiment of the present invention.

FIG. 9 is a configuration diagram showing a start-up control device for a power converter according to a conventional example when the PWM converter has one system.

FIG. 10 is a configuration diagram showing a start-up control device for a power converter according to a conventional example when the PWM converter has two systems.

FIG. 11 is a configuration diagram showing a start-up control device for a power converter according to a conventional modification when the PWM converter has two systems.

[Explanation of symbols]

1 Voltage type PWM converter 2 Converter transformer 3 Circuit breaker 4 Initial charging rectifier 5 Initial charging transformer 6 Circuit breaker 7 DC smoothing capacitor 8 DC voltage detector 9 AC current detector 10 System voltage detector 11 AC voltage detector 12 Synchronous controller 13 DC voltage reference setter 14 Subtractor 15 Converter DC voltage controller 16 Subtractor 17 Converter AC current controller 17a ₁ Proportional calculator 17b ₁ Proportional calculator 17a ₂ Integral calculator 17b ₂ Integral calculator 18 Control signal switcher 19 Triangular wave generator 20 Pulse width modulation control circuit 21 Proportional calculator 22 Zero voltage control signal generator 23 Control signal switcher 24 Adder 25 Control signal switcher 26 Control signal switcher 27 Adder 28 Proportional calculator 29 Control signal switch

Claims (7)

[Claims] 1. A converter having two or more systems connected in parallel to a commercial power supply system via a first circuit breaker, and a converter connected in parallel to the commercial power supply system via a second circuit breaker. The DC output side is connected to the DC output side of the converter via a DC smoothing capacitor, respectively.
System or higher initial charging circuit, AC current detection means for detecting AC current of each converter, system voltage detection means for detecting system voltage of the commercial power supply system, and AC voltage detection for detecting AC voltage of the converter Means and a DC voltage detecting means for detecting the DC voltage of each of the converters, a DC voltage reference setter for sending a DC voltage reference set value, and a switching timing signal according to before and after system integration Before turning on the system, turning off the first circuit breaker and turning on the second circuit breaker to charge the DC smoothing capacitor by the initial charging circuit to operate the converter as an inverter. To generate an AC voltage, and send a voltage control signal for synchronously controlling the system voltage by the system voltage detecting means and the AC voltage by the AC voltage detecting means. While, when the synchronization is the first
Of the DC voltage detected by the DC voltage detecting means and the DC voltage reference setting device. Of two or more systems of converter DC voltage controllers, each of which outputs a control signal for controlling the DC voltage output from each converter based on the deviation from the DC voltage reference set value, and the converter DC voltage controller Based on the deviation between the output and the output of the alternating current detecting means, two or more systems of converter alternating current controllers for sending voltage control signals for controlling the alternating current respectively, and each of the above based on the input control signal. A start-up control device for a power converter, comprising a control circuit having two or more systems of pulse-width modulation control means for pulse-width-modulating each converter. A zero-voltage control signal generator for sending a zero-voltage control signal to the control circuit, and before connecting the system to the converter AC current controller based on the switching timing signal from the synchronous controller. And a control signal switch for giving a control signal based on the zero voltage control signal to control the AC current of each converter to zero on the basis of the zero voltage control signal while controlling the voltage synchronized with the system voltage of the commercial power supply system. The starting control device for the power converter, which is configured to perform control so as to output to the alternating current side. 2. A converter of two or more systems connected in parallel to a commercial power supply system via a first circuit breaker, and a converter connected in parallel to the commercial power supply system via a second circuit breaker. The DC output side is connected to the DC output side of the converter via a DC smoothing capacitor, respectively.
System or higher initial charging circuit, AC current detection means for detecting AC current of each converter, system voltage detection means for detecting system voltage of the commercial power supply system, and AC voltage detection for detecting AC voltage of the converter Means and a DC voltage detecting means for detecting the DC voltage of each of the converters, a DC voltage reference setter for sending a DC voltage reference set value, and a switching timing signal according to before and after system integration Before turning on the system, turning off the first circuit breaker and turning on the second circuit breaker to charge the DC smoothing capacitor by the initial charging circuit to operate the converter as an inverter. To generate an AC voltage, and send a voltage control signal for synchronously controlling the system voltage by the system voltage detecting means and the AC voltage by the AC voltage detecting means. While, when the synchronization is the first
Of the DC voltage detected by the DC voltage detecting means and the DC voltage reference setting device. Of two or more systems of converter DC voltage controllers, each of which outputs a control signal for controlling the DC voltage output from each converter based on the deviation from the DC voltage reference set value, and the converter DC voltage controller Based on the deviation between the output and the output of the alternating current detecting means, two or more systems of converter alternating current controllers for sending voltage control signals for controlling the alternating current respectively, and each of the above based on the input control signal. A start-up control device for a power converter, comprising a control circuit having two or more systems of pulse-width modulation control means for pulse-width-modulating each converter. The zero voltage control signal generator for sending the zero voltage control signal to the control circuit, and before the system integration, the zero voltage control signal is sent to each converter DC voltage controller based on the switching timing signal from the synchronous controller. Only the first control signal switcher for giving the second control signal switcher for giving the zero voltage control signal to the converter AC current controller of either one of the converter system and the pulse width modulation control means of the converter system. A start-up of a power converter characterized in that it is configured to control an AC voltage control system and an AC current control system without interfering with each other by including a signal supply means for providing a voltage control signal by the synchronous controller. Control device. 3. A converter of two or more systems connected in parallel to a commercial power supply system via a first circuit breaker, and a converter connected in parallel to the commercial power supply system via a second circuit breaker. The DC output side is connected to the DC output side of the converter via a DC smoothing capacitor, respectively.
System or higher initial charging circuit, AC current detection means for detecting AC current of each converter, system voltage detection means for detecting system voltage of the commercial power supply system, and AC voltage detection for detecting AC voltage of the converter Means and a DC voltage detecting means for detecting the DC voltage of each of the converters, a DC voltage reference setter for sending a DC voltage reference set value, and a switching timing signal according to before and after system integration Before turning on the system, turning off the first circuit breaker and turning on the second circuit breaker to charge the DC smoothing capacitor by the initial charging circuit to operate the converter as an inverter. To generate an AC voltage, and send a voltage control signal for synchronously controlling the system voltage by the system voltage detecting means and the AC voltage by the AC voltage detecting means. While, when the synchronization is the first
Of the DC voltage detected by the DC voltage detecting means and the DC voltage reference setting device. Of two or more systems of converter DC voltage controllers, each of which outputs a control signal for controlling the DC voltage output from each converter based on the deviation from the DC voltage reference set value, and the converter DC voltage controller Based on the deviation between the output and the output of the alternating current detecting means, two or more systems of converter alternating current controllers for sending voltage control signals for controlling the alternating current respectively, and each of the above based on the input control signal. A start-up control device for a power converter, comprising a control circuit having two or more systems of pulse-width modulation control means for pulse-width-modulating each converter. The zero voltage control signal generator for sending the zero voltage control signal to the control circuit, and before the system integration, the zero voltage control signal is sent to each converter DC voltage controller based on the switching timing signal from the synchronous controller. Only the first control signal switcher for giving the second control signal switcher for giving the zero voltage control signal to the converter AC current controller of either one of the converter system and the pulse width modulation control means of the converter system. By including a signal supply means for giving a voltage control signal by the synchronous controller, the AC voltage control system and the AC current control system are controlled without interfering with each other, and the converter AC current controllers are provided. It is composed of a proportional calculator and an integral calculator, and after the AC voltage output by each converter becomes a constant voltage, it is based on the switching timing signal from the synchronous controller. A voltage control signal based on the deviation between the output of the converter DC voltage controller and the output of the AC current detecting means is passed through the second control signal switch which is switched to the proportional calculator side of the converter AC current controller. And a third control signal switcher for outputting the voltage control signal to the integration calculator side of the converter AC current controller after the AC current output by each converter reaches a constant value. A starting control device for a power converter characterized by the above. 4. A converter of two or more systems connected in parallel to a commercial power supply system via a first circuit breaker, and a converter connected in parallel to the commercial power supply system via a second circuit breaker. The DC output side is connected to the DC output side of the converter via a DC smoothing capacitor, respectively.
System initial charging circuit, AC current detecting means for detecting AC current of each converter, system voltage detecting means for detecting system voltage of the commercial power supply system, and AC voltage detecting means for detecting AC voltage of the converter And a DC voltage detecting means for detecting the DC voltage of each of the converters, a DC voltage reference setter for sending out a DC voltage reference set value, and a switching timing signal according to before and after system connection. By sending out and turning off the first circuit breaker before turning on the system and turning on the second circuit breaker to charge the DC smoothing capacitor by the initial charging circuit and operate the converter as an inverter. An AC voltage is generated, and a voltage control signal for synchronously controlling the system voltage by the system voltage detecting means and the AC voltage by the AC voltage detecting means is transmitted. Together, when synchronized to turn on the first circuit breaker, and turns off the second circuit breaker,
Output from each of the converters on the basis of a synchronous controller to be inserted in the system, and a deviation between the DC voltage detected by the DC voltage detecting means and the DC voltage reference set value set by the DC voltage reference setter. Two or more systems of converter DC voltage controllers for sending control signals for controlling the DC voltage, and AC currents based on the deviation between the output of the converter DC voltage controller and the output of the AC current detecting means. Two or more systems of converter AC current controllers for sending voltage control signals for controlling, and two or more systems of pulse width modulation control means for performing pulse width modulation control on each of the converters based on the input voltage control signals. In a start-up control device for a power converter equipped with a control circuit having a A control signal switch that gives a signal based on the deviation of the pressure to each converter DC voltage controller, and the voltage control signal from the synchronous controller is added to the voltage control signal output from each converter AC current controller. And an adding means for sending the pulse width modulation control means to each of the pulse width modulation control means. 5. A converter having two or more systems connected in parallel to a commercial power supply system via a first circuit breaker, and a converter connected in parallel to the commercial power supply system via a second circuit breaker. The DC output side is connected to the DC output side of the converter via a DC smoothing capacitor, respectively.
System initial charging circuit, AC current detecting means for detecting AC current of each converter, system voltage detecting means for detecting system voltage of the commercial power supply system, and AC voltage detecting means for detecting AC voltage of the converter And a DC voltage detecting means for detecting the DC voltage of each of the converters, a DC voltage reference setter for sending out a DC voltage reference set value, and a switching timing signal according to before and after system connection. By sending out and turning off the first circuit breaker before turning on the system and turning on the second circuit breaker to charge the DC smoothing capacitor by the initial charging circuit and operate the converter as an inverter. An AC voltage is generated, and a voltage control signal for synchronously controlling the system voltage by the system voltage detecting means and the AC voltage by the AC voltage detecting means is transmitted. Together, when synchronized to turn on the first circuit breaker, and turns off the second circuit breaker,
Output from each of the converters on the basis of a synchronous controller to be inserted in the system, and a deviation between the DC voltage detected by the DC voltage detecting means and the DC voltage reference set value set by the DC voltage reference setter. Two or more systems of converter DC voltage controllers for sending control signals for controlling the DC voltage, and AC currents based on the deviation between the output of the converter DC voltage controller and the output of the AC current detecting means. Two or more systems of converter AC current controllers for sending voltage control signals for controlling, and two or more systems of pulse width modulation control means for performing pulse width modulation control on each of the converters based on the input voltage control signals. A start-up control device for a power converter including a control circuit having a zero voltage control signal for sending a zero voltage control signal to the control circuit. Before connecting the generator and the system, the deviation of the DC voltage detected by the DC voltage detecting means in the converter DC voltage controller of one of the converter systems based on the switching timing signal from the synchronous controller Based on the first control signal switching device, a second control signal switching device for supplying the zero voltage control signal to the converter AC current controller of the remaining converter system, and the pulse width modulation control of the remaining converter system. It is characterized in that the DC voltage control and the AC voltage control and the AC current control are controlled without interfering with each other by providing only the means with a signal supply means for giving a voltage control signal by the synchronous controller. Power converter startup control device. 6. A converter having two or more systems connected in parallel to a commercial power supply system via a first circuit breaker, and a converter connected in parallel to the commercial power supply system via a second circuit breaker. The DC output side is connected to the DC output side of the converter via a DC smoothing capacitor, respectively.
System initial charging circuit, AC current detecting means for detecting AC current of each converter, system voltage detecting means for detecting system voltage of the commercial power supply system, and AC voltage detecting means for detecting AC voltage of the converter And a DC voltage detecting means for detecting the DC voltage of each of the converters, a DC voltage reference setter for sending out a DC voltage reference set value, and a switching timing signal according to before and after system connection. By sending out and turning off the first circuit breaker before turning on the system and turning on the second circuit breaker to charge the DC smoothing capacitor by the initial charging circuit and operate the converter as an inverter. An AC voltage is generated, and a voltage control signal for synchronously controlling the system voltage by the system voltage detecting means and the AC voltage by the AC voltage detecting means is transmitted. Together, when synchronized to turn on the first circuit breaker, and turns off the second circuit breaker,
Output from each of the converters on the basis of a synchronous controller to be inserted in the system, and a deviation between the DC voltage detected by the DC voltage detecting means and the DC voltage reference set value set by the DC voltage reference setter. Two or more systems of converter DC voltage controllers for sending control signals for controlling the DC voltage, and AC currents based on the deviation between the output of the converter DC voltage controller and the output of the AC current detecting means. Two or more systems of converter AC current controllers for sending voltage control signals for controlling, and two or more systems of pulse width modulation control means for performing pulse width modulation control on each of the converters based on the input voltage control signals. A start-up control device for a power converter including a control circuit having a zero voltage control signal for sending a zero voltage control signal to the control circuit. Before connecting the generator and the system, a signal based on the deviation of the DC voltage detected by the DC voltage detecting means is given to the converter DC voltage controllers based on the switching timing signal from the synchronous controller. A second control voltage switching device and a second converter AC current controller of either one of the converter systems for applying the zero voltage control signal
Control signal switcher and signal supply means for supplying a voltage control signal by the synchronous controller only to the pulse width modulation control means of the converter system, and control AC voltage control and AC current control without interfering with each other. With the configuration
Each converter AC current controller is composed of a proportional calculator and an integral calculator, and after the AC voltage output by each converter becomes a constant voltage, it is switched based on a switching timing signal from the synchronous controller. A voltage control signal based on the deviation between the output of the converter DC voltage controller and the output of the AC current detecting means is output to the proportional calculator side of the converter AC current controller via the second control signal switch. And a third control signal switcher for outputting the voltage control signal to the integration calculator side of the converter AC current controller after the AC current output by each converter becomes a constant value, A start-up control device for a power converter, which is configured to control DC voltage control and AC voltage control and AC current control without interfering with each other. 7. A converter of two or more systems connected in parallel to a commercial power supply system via a first circuit breaker, and a converter connected in parallel to the commercial power supply system via a second circuit breaker. At the same time, the DC output side is connected to the DC output side for one system of the converter via a DC smoothing capacitor, one system of initial charging circuit, AC current detecting means for detecting the AC current of each converter, A system voltage detecting means for detecting a system voltage of a commercial power system, an AC voltage detecting means for detecting an AC voltage of the converter, and a DC voltage detecting means for detecting a DC voltage of each of the converters, and a DC voltage reference A DC voltage reference setter that sends a set value, and a switching timing signal according to before and after system integration, and before the system integration, turn off the first circuit breaker and turn off the first circuit breaker. The circuit breaker No. 2 is turned on, the direct current smoothing capacitor is charged by the initial charging circuit and the converter is operated as an inverter to generate an alternating voltage, and the system voltage by the system voltage detecting means and the alternating voltage detecting means are generated. A synchronous controller that sends out a voltage control signal for synchronously controlling the AC voltage and, when synchronized, turns on the first circuit breaker and turns off the second circuit breaker so that the system is connected together. Control for controlling the DC voltage output from each of the converters based on the deviation between the DC voltage detected by each of the DC voltage detecting means and the DC voltage reference set value set by the DC voltage reference setter. Two or more systems of converter DC voltage controllers for transmitting signals, an output of the converter DC voltage controller and an output of the AC current detecting means Two or more converter AC current controllers for sending voltage control signals for controlling AC currents based on deviations, and two systems for pulse width modulation control of the converters on the basis of input voltage control signals In a start-up control device for a power converter including a control circuit having the above pulse width modulation control means, in the control circuit, a zero-voltage control signal generator that sends a zero-voltage control signal, and before the system integration, First control signal switching for giving a signal based on the deviation of the DC voltage detected by the DC voltage detecting means to the converter DC voltage controller of either one of the converter systems based on the switching timing signal from the synchronous controller. Controller, a second control signal switching device for providing the zero-voltage control signal to the converter AC current controller of the remaining converter system, and the remaining controller. By providing only the pulse width modulation control means of the data system with the signal supply means for giving the voltage control signal by the synchronous controller, the direct current voltage control and the alternating current voltage control and the alternating current control are controlled without interfering with each other. A start-up control device for a power converter having a configuration.