JPH08251701A - Electric power unit for vehicle - Google Patents

Abstract

PURPOSE: To ensure safety by surely discharging a filter capacitor even when a filter capacitor discharging contactor fails. CONSTITUTION: In a power unit for a vehicle, when a main circuit is turned off, not applying line voltage to an input end is detected by a line voltage detecting means 13. When the charge of a filter capacitor 7 is detected by a detecting means 14 for detecting the voltage of the filter capacitor 7, an overvoltage-protective switching element 8 of a power converter circuit 6 is turned on by a protective means 15, to discharge the filter capacitor 7 through an overvoltage discharging resistor 9. In this way, a residual charge in the filter capacitor 7 is consumed by the overvoltage discharging resistor 9, to prevent the filter capacitor 7 from being left at high voltage after the main circuit is turned off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle power supply device.

[0002]

2. Description of the Related Art Generally, a vehicle power supply device has a structure as shown in FIG. That is, the voltage of the overhead wire 1 is applied to the disconnector 2, the contactor 3, the filter reactor 4, and the semiconductor breaker 5.
It is taken in through the inverter 6 which is a power conversion circuit and the filter capacitor 7 which is provided in parallel with this via the inverter, and the inverter 6 converts the direct current into the alternating current to output the alternating current voltage. Further, in order to protect the inverter 6 from overvoltage, an overvoltage suppressing thyristor 8 and an overvoltage discharging resistor 9, and a filter capacitor discharging contactor 10 for discharging the electric charge remaining in the filter capacitor 7 when the main circuit is stopped. A filter capacitor discharging resistor 11 is provided between the B contact side of the disconnector 2 and the grounding point. A control circuit 12 is provided to control the operation of each part of these circuits, and the overhead wire voltage is supplied to the inverter 6 and the filter capacitor 7 via the disconnector 2, the contactor 3, the filter reactor 4, and the semiconductor breaker 5. Is supplied to the inverter 6 and the switching control of the inverter 6 is performed to convert the voltage into a predetermined AC voltage and output the AC voltage.

When stopping the apparatus, the control circuit 12 stops the switching control of the inverter 6, turns off the semiconductor circuit breaker 5, turns off the contactor 3 to disconnect the connection with the overhead line 1, and then In order to discharge the electric charge remaining in the filter capacitor 7, the discharging contactor 10 is turned on and the discharging resistor 11 consumes the electric charge of the filter capacitor 7.

The control circuit 12 further causes the overvoltage suppressing thyristor 8 to instantly turn on to cause an overvoltage to the overvoltage discharge resistor 9 when the overhead wire voltage rises rapidly and an overvoltage is applied to the input end of the inverter 6. Is conducted and consumed to perform a protective operation of lowering the voltage of the filter capacitor 7.

[0005]

However, in such a conventional vehicle power supply device, if the filter capacitor discharge contactor becomes inoperable for some reason and does not turn on when the main circuit is stopped, the filter capacitor does not turn on. There is a problem that the electric charge accumulated in the battery is not discharged and a high voltage flows when performing inspection work, which is dangerous.

The present invention has been made in view of the above conventional problems, and even if a failure occurs in the contactor for discharging the filter capacitor, the charge of the filter capacitor can be surely discharged, and the inspection work is safe. It is an object of the present invention to provide a vehicular power supply device capable of ensuring the reliability.

The present invention also provides a vehicle power supply device that does not have a filter capacitor discharge contactor and can reliably discharge the electric charge remaining in the filter capacitor when the main circuit is stopped. The purpose is to do.

[0008]

According to a first aspect of the present invention, there is provided a vehicle power supply device, a power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input end of the power conversion circuit, and a filter capacitor. Is connected in parallel with the protection resistor and the protection switching element in series, and the overvoltage protection circuit is connected in parallel with the filter capacitor, and the discharge resistor and the discharge contactor are connected in series. A connected circuit for discharging a filter capacitor, a detection means for detecting the voltage across the filter capacitor, and a protection switching element that is ignited when the detection value of the detection means exceeds a predetermined overvoltage set value. Overvoltage protection means and control means for turning on the discharge contactor when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off. Monitors the input voltage to the power conversion circuit, after the input voltage to the power converter circuit has detected that it is not supplied, when the detected value of the detection means is not reduced,
And a discharge means for firing the protective switching element.

According to a second aspect of the present invention, there is provided a vehicle power supply device including a power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input end of the power conversion circuit, and a filter capacitor connected in parallel. A filter capacitor formed by connecting a protection resistor and a protection switching element in series with an overvoltage protection circuit, and a filter capacitor connected in parallel, and a discharge resistor and a discharge contactor connected in series. A discharge circuit, a detection means for detecting the voltage across the filter capacitor, an overvoltage protection means for firing a protection switching element when the detection value of the detection means exceeds a predetermined overvoltage set value, and an electric power When the operation of the conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the control means for turning on the discharge contactor and the detection means for the detection means Monitors the input voltage to the power conversion circuit and the signal output means that outputs the discharge command signal when the value is above the preset discharge setting value, and detects that the input voltage is not supplied to the power conversion circuit After doing
When the discharge command signal is output from the signal output means,
And a discharge means for firing the protective switching element.

According to a third aspect of the present invention, there is provided a vehicle power supply device having a power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power conversion circuit, and a filter capacitor connected in parallel. A circuit for discharging a filter capacitor formed by connecting a discharging resistor and a discharging contactor in series, a detecting means for detecting a voltage across the filter capacitor, and a power converting circuit for stopping the operation of the power converting circuit. When the supply voltage is cut off, the control means for turning on the discharge contactor and the input voltage to the power conversion circuit are monitored, and after detecting that the input voltage is not supplied to the power conversion circuit, the detection means And a discharge means for firing a plurality of switching elements when the detected value does not decrease.

According to a fourth aspect of the present invention, there is provided a vehicle power supply device including a power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power conversion circuit, and a filter capacitor connected in parallel. A circuit for discharging a filter capacitor formed by connecting a discharging resistor and a discharging contactor in series, a detecting means for detecting a voltage across the filter capacitor, and a power converting circuit for stopping the operation of the power converting circuit. Control means for turning on the discharge contactor when the supply voltage is cut off, signal output means for outputting a discharge command signal when the detection value of the detection means is equal to or greater than a predetermined discharge set value, and power conversion When the discharge command signal is output from the signal output means after monitoring the input voltage to the circuit and detecting that the input voltage is not supplied to the power conversion circuit, It is obtained by a discharge means for firing the switching element.

According to a fifth aspect of the present invention, there is provided a vehicle power supply device including a power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power conversion circuit, and a filter capacitor connected in parallel. An overvoltage protection circuit consisting of a protection resistor and a protection switching element connected in series, detection means for detecting the voltage across the filter capacitor, and the detection value of the detection means exceeds the preset overvoltage setting value. The overvoltage protection means that fires the protection switching element and the input voltage to the power conversion circuit are monitored, and after detecting that the input voltage is not supplied to the power conversion circuit, the detection value of the detection means is detected. Discharge means for igniting the protection switching element when the voltage does not decrease.

According to a sixth aspect of the present invention, there is provided a vehicle power supply device including a power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input end of the power conversion circuit, and a filter capacitor connected in parallel. An overvoltage protection circuit consisting of a protection resistor and a protection switching element connected in series, detection means for detecting the voltage across the filter capacitor, and the detection value of the detection means exceeds the preset overvoltage setting value. To the power conversion circuit, an overvoltage protection means for firing the protection switching element, a signal output means for outputting a discharge command signal when the detection value of the detection means is equal to or more than a predetermined discharge set value, Of the discharge command signal is output from the signal output unit after detecting that the input voltage is not supplied to the power conversion circuit by monitoring the input voltage of When, in which the protective switching device and a discharge means for firing.

A vehicle power supply device according to a seventh aspect of the present invention detects a power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power conversion circuit, and a voltage across the filter capacitor. After monitoring the input voltage to the detection means and the power conversion circuit and detecting that the input voltage is not supplied to the power conversion circuit, the switching elements are ignited when the detection value of the detection means does not decrease. And a discharge means for performing the discharge.

According to another aspect of the present invention, there is provided a vehicle power supply device having a power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power conversion circuit, and a voltage across the filter capacitor. The detection means, the signal output means for outputting the discharge command signal when the detection value of the detection means is equal to or more than the preset discharge setting value, and the input voltage to the power conversion circuit is monitored by monitoring the input voltage to the power conversion circuit. And a discharge means for igniting the plurality of switching elements when the discharge command signal is output from the signal output means after it is detected that the discharge command signal is not supplied.

[0016]

In the vehicle power supply device according to the present invention, when the detected value of the detection means exceeds the predetermined overvoltage set value during the operation of the power conversion circuit, the overvoltage protection means causes the protection switching means to operate. It is turned on and the overvoltage current is consumed by the protective resistor. Then, when the operation of the power conversion circuit is stopped and the voltage supplied to the power conversion circuit is shut off, the control means turns on the discharge contactor to consume the electric charge remaining in the filter capacitor with the discharge resistor. Let

However, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the input voltage to the power conversion circuit is monitored and it is detected that the input voltage is not supplied. After that, when the detection value of the voltage detecting means of the filter capacitor does not decrease, the discharging means ignites the protection switching element so that the charge remaining in the filter capacitor is consumed by the protection resistor. Make sure that the filter capacitor is not kept at a high voltage after the power conversion circuit is stopped.

In the power supply device for a vehicle according to the second aspect of the present invention, when the detection value of the detection means exceeds a predetermined overvoltage set value during the operation of the power conversion circuit, the overvoltage protection means causes the protection switching means to operate. It is turned on and the overvoltage current is consumed by the protective resistor. Then, when the operation of the power conversion circuit is stopped and the voltage supplied to the power conversion circuit is shut off, the control means turns on the discharge contactor to consume the electric charge remaining in the filter capacitor with the discharge resistor. Let

However, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the input voltage to the power conversion circuit is monitored and it is detected that the input voltage is not supplied. Later, when the signal output means is outputting the discharge command signal because the detection value of the voltage across the filter capacitor is greater than or equal to the discharge setting value, the discharge means should ignite the protection switching element. Thus, the electric charge remaining in the filter capacitor is consumed by the protective resistor, and the filter capacitor is prevented from being held at a high voltage after the power conversion circuit is stopped.

In the vehicle power supply device according to the third aspect of the present invention, when the operation of the power conversion circuit is stopped and the voltage supplied to the power conversion circuit is cut off, the control means turns on the discharge contactor to filter the filter capacitor. The remaining electric charge is consumed by the discharging resistor.

However, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the input voltage to the power conversion circuit is monitored and it is detected that the input voltage is not supplied. After that, when the detection value of the voltage across the filter capacitor does not decrease, the discharging device fires a plurality of switching elements so that the electric charge remaining in the filter capacitor is consumed by the power conversion circuit to convert the power. Make sure that the filter capacitor is not kept at high voltage after the circuit is stopped.

In the vehicle power supply device according to the present invention, when the operation of the power conversion circuit is stopped and the voltage supplied to the power conversion circuit is cut off, the control means turns on the discharge contactor to filter the filter capacitor. The remaining electric charge is consumed by the discharging resistor.

However, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the input voltage to the power conversion circuit is monitored and it is detected that the input voltage is not supplied. After that, while the signal output unit is outputting the discharge command signal because the detection value of the voltage across the filter capacitor is greater than or equal to the set value for discharge, the discharge unit may ignite the plurality of switching elements. Thus, the electric charge remaining in the filter capacitor is consumed in the power conversion circuit so that the filter capacitor is not held at a high voltage after the power conversion circuit is stopped.

According to another aspect of the present invention, in the vehicle power supply device, when the detection value of the detection means exceeds the predetermined overvoltage set value during the operation of the power conversion circuit, the overvoltage protection means causes the protection switching means to operate. It is turned on and the overvoltage current is consumed by the protective resistor.

Then, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the input voltage to the power conversion circuit is monitored and it is detected that the input voltage is not supplied. After that, when the detection value of the voltage across the filter capacitor does not decrease, the discharge switching means fires the protection switching element so that the charge remaining in the filter capacitor is consumed by the protection resistor. Make sure that the filter capacitor is not kept at high voltage after the conversion circuit is stopped.

According to the sixth aspect of the present invention, when the detected value of the detection means exceeds the predetermined overvoltage set value during the operation of the power conversion circuit, the overvoltage protection means activates the protection switching means. It is turned on and the overvoltage current is consumed by the protective resistor.

Then, when the operation of the power conversion circuit is stopped and the voltage supplied to the power conversion circuit is cut off, the input voltage to the power conversion circuit is monitored, and after detecting that the input voltage is not supplied, By igniting the switching element for protection by the discharging means when the signal output means is outputting the discharge command signal because the detection value of the voltage across the filter capacitor is greater than or equal to the set value for discharging The electric charge remaining in the filter capacitor is consumed by the protective resistor so that the filter capacitor is not kept at a high voltage after the power conversion circuit is stopped.

According to the seventh aspect of the present invention, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is shut off, the input voltage to the power conversion circuit is monitored and the input voltage is monitored. After detecting that no voltage is being supplied, when the detection value of the voltage across the filter capacitor does not decrease, the discharge means fires a plurality of switching elements to cause the charge remaining in the filter capacitor. Is consumed by the power conversion circuit so that the filter capacitor is not kept at a high voltage after the power conversion circuit is stopped.

In the vehicle power supply device of the eighth aspect of the invention, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the input voltage to the power conversion circuit is monitored and the input voltage is monitored. After detecting that the voltage is not supplied, the discharge means is output when the signal output means is outputting the discharge command signal because the detection value of the voltage across the filter capacitor is greater than or equal to the discharge set value. By igniting a plurality of switching elements, the electric charge remaining in the filter capacitor is consumed in the power conversion circuit, and the filter capacitor is not held at a high voltage after the power conversion circuit is stopped.

[0030]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows the main circuit configuration of the first embodiment of the present invention. Like the conventional example shown in FIG. 7, the high voltage DC of the overhead wire 1 is used as a disconnector 2, a contactor 3, a filter reactor 4, a semiconductor. The inverter 6 which is a power conversion circuit and the filter capacitor 7 provided in parallel with the power conversion circuit are taken in through the circuit breaker 5, and the inverter 6 converts DC into AC and outputs AC voltage. Further, in order to protect the inverter 6 from overvoltage, an overvoltage suppressing thyristor 8 and an overvoltage discharging resistor 9, and a filter capacitor discharging contactor 10 for discharging the electric charge remaining in the filter capacitor 7 when the main circuit is stopped. A filter capacitor discharging resistor 11 is provided between the B contact side of the disconnector 2 and the grounding point. A control circuit 12 is provided for controlling the operation of each part of these circuits, and the overhead wire voltage is supplied to the inverter 6 and the filter capacitor 7 via the disconnector 2, the contactor 3, the filter reactor 4, and the semiconductor breaker 5. The voltage is supplied and the switching control of the inverter 6 is performed to convert the voltage into a predetermined AC voltage and output the AC voltage.

When the apparatus is stopped, the control circuit 12 stops switching control of the inverter 6, turns off the semiconductor circuit breaker 5, turns off the contactor 3 to disconnect the connection with the overhead line 1, and then In order to discharge the electric charge remaining in the filter capacitor 7, the discharging contactor 10 is turned on and the discharging resistor 11 consumes the electric charge of the filter capacitor 7. The control circuit 12 also instantly turns on the overvoltage suppressing thyristor 8 to quickly turn on the overvoltage suppressing thyristor 8 when the overhead wire voltage rises rapidly and the overvoltage is applied to the input terminal of the inverter 6.
A protective operation for lowering the voltage of the filter capacitor 7 is performed by guiding and consuming the overvoltage.

As a feature of this embodiment, an overhead line voltage detector 13 for detecting whether or not an overhead line voltage is applied to the input terminal and a filter capacitor voltage detector 14 for detecting the voltage across the filter capacitor 7 are provided. The detection signals are input to the control circuit 12.

The control circuit 12 further includes a protection operation circuit 15 for performing a protection operation for discharging the remaining charge when the remaining charge is stored in the filter capacitor 7 when the main circuit is stopped.

FIG. 2 shows the protection operation circuit 15 provided in the first embodiment, and the signal S1 from the overhead wire voltage detector 13 is shown.
And the signal S2 from the filter capacitor voltage detector 14, the AND circuit 16 that outputs the operation signal P1 to the overvoltage suppressing thyristor 8 when the overhead wire voltage is not applied and the filter capacitor voltage exists, and the filter An indicator lamp 17 is provided which lights up when there is a capacitor voltage.

Next, the operation of the first embodiment having the above structure will be described. During normal operation, the disconnector 2 is turned on,
The control circuit 12 turns on the contactor 3 and the semiconductor circuit breaker 5 to supply an overhead wire voltage to the filter capacitor 7 and the inverter 6, and performs switching control of the inverter 6 so that desired AC power is output from the inverter 6.

The control circuit 12 monitors the input voltage of the inverter 6, and upon detecting the overvoltage, immediately turns on the overvoltage suppressing thyristor 8 to discharge the overvoltage from the overvoltage discharging resistor 9
To discharge and protect the inverter 6 from overvoltage.

When the main circuit is stopped, the switching control of the inverter 6 is stopped and the semiconductor breaker 5 and the contactor 3 are turned off according to a predetermined sequence. Then, the disconnector 2 is manually cut. When the disconnector 2 is turned off, its B contact is on. Therefore, when the filter capacitor discharging contactor 10 is normal, the control circuit 12 causes the filter capacitor discharging contactor 10 to operate.
Is turned on to guide the remaining electric charge of the filter capacitor 7 to the filter capacitor discharging resistor 11 to be consumed, so that the filter capacitor 7 is not held at a high voltage.

On the other hand, in the protection operation circuit 15, the voltage detection signal S1 from the overhead wire voltage detector 13 and the voltage detection signal S2 from the filter capacitor voltage detector 14 are input. Therefore, if the filter capacitor discharging contactor 11 is operating normally, the overhead wire voltage is not applied, the filter capacitor voltage is also 0, and the operation signal P1 is not output from the AND circuit 16.

However, if the filter capacitor discharging contactor 11 becomes inoperative for some reason, the electric charge remains in the filter capacitor 7 and the signal S2 with voltage is input from the filter capacitor voltage detector 14. become. Therefore, the indicator lamp 17 lights up to indicate that the filter capacitor 7 has not been discharged, and the AND circuit 16 outputs the operation signal P1 to the overvoltage suppressing thyristor 8 to turn it on to discharge the charge of the filter capacitor 7 for overvoltage discharging. The voltage is led to the resistor 9 and consumed to reduce the voltage across the filter capacitor 7.

The discharge of the filter capacitor 7 progresses, and the voltage detection signal S2 from the filter capacitor voltage detector 14 is detected.
When is decreased to below a preset threshold value, the indicator lamp 17 is turned off, and the AND circuit 16 does not output the operation signal P1 either, thereby ending the discharging of the filter capacitor 7.

As a result, even if a situation occurs in which the contactor 10 for discharging the filter capacitor does not operate when the main circuit is stopped and discharge of the filter capacitor cannot be performed through this contactor 10, the overvoltage suppressing thyristor 8 and the overvoltage discharge are generated. The filter capacitor 7 can be discharged by using the resistor 9 for use, and the risk of electric shock due to the filter capacitor 7 being held at a high voltage during inspection work can be eliminated.

Next, the structure of the protection operation circuit 150 used in the second embodiment of the present invention will be described with reference to FIG.
The protection operation circuit 150 is used in place of the protection operation circuit 15 of the first embodiment shown in FIG. 2, and is a manual operation for causing the protection operation circuit 15 shown in FIG. 2 to perform a filter capacitor discharge operation. A switch 18 is additionally provided, and an AND circuit 160 is provided instead of the AND circuit 16.

The AND circuit 160 outputs the signal S1 from the overhead wire voltage detector 13 indicating no voltage, as in the first embodiment.
And a signal S2 indicating that there is a voltage from the filter capacitor voltage detector 14, and a closing signal S3 of the manual switch 18
When inputting, the operation signal P1 is output.

The protection operation circuit 150 of the second embodiment.
Does not perform the forced discharge operation of the filter capacitor 7 unless the manual switch 18 is operated.

Further, when the operator operates the manual switch 18 before the inspection when the main circuit is stopped and the closing signal S3 is input to the protection operation circuit 150, the overhead line voltage detector 1
3 and the voltage detection signal S2 from the filter capacitor voltage detector 14, the filter capacitor voltage is 0 because the filter capacitor discharge contactor 10 is operating normally. , AND circuit 160 does not output the operation signal P1.

However, when the filter capacitor discharging contactor 10 is inoperative for some reason and electric charges remain in the filter capacitor 7, and the signal S2 with voltage is input from the filter capacitor voltage detector 14. , The indicator lamp 17 lights up to indicate that the filter capacitor 7 is not discharged, and the AND circuit 160
Outputs the operation signal P1 to the overvoltage suppressing thyristor 8 to turn it on, and guides the charge of the filter capacitor 7 to the overvoltage discharging resistor 9 to be consumed, thereby lowering the voltage across the filter capacitor 7.

As the discharge of the filter capacitor 7 progresses, the voltage detection signal S2 from the filter capacitor voltage detector 14
When is decreased to below the preset threshold value, the indicator lamp 17 is turned off, and the AND circuit 160 does not output the operation signal P1 either, thereby ending the discharging of the filter capacitor 7.

As a result, even if a situation occurs in which the filter capacitor discharging contactor 10 becomes inoperative when the main circuit is stopped and the filter capacitor discharging cannot be performed through the contactor 10, the operation of turning on the manual switch 18 is performed. By doing so, the filter capacitor 7 can be discharged by using the overvoltage suppressing thyristor 8 and the overvoltage discharging resistor 9, eliminating the risk of electric shock due to the filter capacitor 7 being held at a high voltage during inspection work. Will be able to.

Next, a third embodiment of the present invention will be described with reference to FIGS.
It will be described based on. The main circuit configuration of the vehicle power supply device of the third embodiment is common to that shown in FIG. 1, and the internal configuration of the protection operation circuit 15 is common to the protection operation circuit 15 of the first embodiment shown in FIG. Therefore, the output condition of the operation signal P1 of the protection operation circuit 15 itself is the same as that of the first embodiment. The feature of this embodiment is that the switching element of the inverter 6 is operated by the operation signal P1 of the protection operation circuit 15.

That is, the protection operation circuit 15 shown in FIG.
Is a voltage detection signal S1 from the overhead line voltage detector 13 and a voltage detection signal S2 from the filter capacitor voltage detector 14.
Enter Therefore, if the contactor 10 for discharging the filter capacitor is operating normally, the overhead wire voltage is not applied and the filter capacitor voltage is also 0.
The operation signal P1 is not output from the D circuit 16.

However, if the filter capacitor discharging contactor 10 of the main circuit in FIG. 1 becomes inoperative for some reason, the electric charge remains in the filter capacitor 7 and the filter capacitor voltage detector 14 outputs a signal with voltage. S2 will be input. Therefore,
The indicator lamp 17 lights to indicate that the filter capacitor 7 has not been discharged, and the AND circuit 16 causes the operation signal P1 to be discharged.
Is input to the switching element group of the inverter 6 to operate, and the charge of the filter capacitor 7 is guided to the inverter 6 and consumed to reduce the voltage across the filter capacitor 7.

As described above, according to the vehicle power supply device of the third embodiment, the filter capacitor discharging contactor 10 becomes inoperative when the main circuit is stopped, and the filter capacitor discharging cannot be performed through the contactor 10. Even if a situation occurs, the inverter 6 can be operated again to discharge the filter capacitor 7, and the risk of electric shock due to the filter capacitor 7 being held at a high voltage during inspection work can be eliminated.

Next, a fourth embodiment of the present invention will be described with reference to FIGS.
It will be described based on. The main circuit configuration of the vehicle power supply device of the fourth embodiment is common to that shown in FIG. 1, and the internal configuration of the protection operation circuit 150 is common to the protection operation circuit of the second embodiment shown in FIG. Therefore, the output condition of the operation signal P1 of the protection operation circuit 150 itself is the same as that of the second embodiment. The feature of the fourth embodiment resides in that the switching element of the inverter 6 is operated by the operation signal P1 of the protection operation circuit 150.

That is, the protection operation circuit 15 shown in FIG.
When 0, the forced discharge operation of the filter capacitor 7 is not performed unless the manual switch 18 is operated.

Further, when the operator operates the manual switch 18 before the inspection when the main circuit is stopped and the closing signal S3 is input to the protection operation circuit 150, the overhead line voltage detector 1
3 and the voltage detection signal S2 from the filter capacitor voltage detector 14, the filter capacitor voltage is 0 because the filter capacitor discharge contactor 10 is operating normally. , AND circuit 160 does not output the operation signal P1.

However, when the filter capacitor discharging contactor 10 is inoperative for some reason, the charge remains in the filter capacitor 7, and the signal S2 with voltage is input from the filter capacitor voltage detector 14. , The indicator lamp 17 lights up to indicate that the filter capacitor 7 is not discharged, and the AND circuit 160
Causes the operation signal P1 to operate the switching element group of the inverter 6, and charges the filter capacitor 7 to the inverter 6
To reduce the voltage across the filter capacitor 7.

As a result, even if the filter capacitor discharging contactor 10 becomes inoperative when the main circuit is stopped and the filter capacitor discharging cannot be performed through the contactor 10, the operation of turning on the manual switch 18 is performed. By doing so, the inverter 6 can be operated again to discharge the filter capacitor 7, and the risk of electric shock due to the filter capacitor 7 being held at a high voltage during inspection work can be eliminated.

Next, a vehicle power supply device according to a fifth embodiment of the present invention will be described with reference to FIGS. 2 and 6. The vehicle power supply device according to the fifth embodiment has the main circuit configuration shown in FIG.
The feature is that the filter capacitor discharging contactor and the filter capacitor discharging resistor are not provided, and the filter capacitor discharging is performed by the overvoltage suppressing thyristor and the overvoltage discharging resistor. Explaining the configuration,
The high voltage DC of the overhead wire 1 is taken into an inverter 6 which is a power conversion circuit and a filter capacitor 7 provided in parallel with the same through a disconnector 2, a contactor 3, a filter reactor 4 and a semiconductor circuit breaker 5, and the inverter 6 DC-AC conversion is performed to output an AC voltage. In order to protect the inverter 6 against overvoltage, an overvoltage suppressing thyristor 8 and an overvoltage discharging resistor 9 are provided between the B contact side of the disconnector 2 and the ground point. A control circuit 120 is provided to control the operation of each part of these circuits, and the overhead wire voltage is supplied to the inverter 6 and the filter capacitor 7 via the disconnector 2, the contactor 3, the filter reactor 4, and the semiconductor breaker 5. The voltage is supplied and the switching control of the inverter 6 is performed to convert the voltage into a predetermined AC voltage and output the AC voltage.

Further, the control circuit 120 instantly turns on the overvoltage suppressing thyristor 8 to apply the overvoltage to the overvoltage discharging resistor 9 when the overhead wire voltage rises rapidly and the overvoltage is applied to the input end of the inverter 6. By conducting and consuming it, a protection operation of lowering the voltage of the filter capacitor 7 is performed. The control circuit 120 is provided with the protection operation circuit 15 having the configuration shown in FIG. 2 which is common to the first embodiment.

Next, the operation of the vehicle power supply device of the fifth embodiment will be described. During normal operation, the disconnector 2 is turned on and the control circuit 120 causes the contactor 3 and the semiconductor breaker 5 to operate.
Is supplied to supply the overhead line voltage to the filter capacitor 7 and the inverter 6, and the switching power of the inverter 6 is controlled to output the desired AC power from the inverter 6.

The control circuit 120 monitors the input voltage of the inverter 6, and upon detecting the overvoltage, immediately turns on the overvoltage suppressing thyristor 8 to guide the overvoltage to the overvoltage discharging resistor 9 to discharge it, thereby causing the inverter 6 to be discharged from the overvoltage. Protect.

When the main circuit is stopped, the switching control of the inverter 6 is stopped and the semiconductor breaker 5 and the contactor 3 are turned off according to a predetermined sequence. Then, the disconnector 2 is manually cut. When the disconnector 2 is turned off, its B contact is on.

In the protection operation circuit 15, the overhead line voltage detector 1
3 and the voltage detection signal S2 from the filter capacitor voltage detector 14 are input. Therefore,
If the overhead wire voltage is not applied and the filter capacitor voltage is also 0, the AND circuit 16 outputs the operation signal P1.
Is not output.

However, the electric charge remains in the filter capacitor 7, and when the signal S2 with voltage is input from the filter capacitor voltage detector 14, the indicator lamp 17 is turned on and the filter capacitor 7 is not discharged. At the same time, the AND circuit 16 outputs the operation signal P1 to the overvoltage suppressing thyristor 8 to turn it on, guide the electric charge of the filter capacitor 7 to the overvoltage discharging resistor 9 and consume it to reduce the voltage across the filter capacitor 7. Let

The discharge of the filter capacitor 7 progresses, and the voltage detection signal S2 from the filter capacitor voltage detector 14 is detected.
When is decreased to below a preset threshold value, the indicator lamp 17 is turned off, and the AND circuit 16 does not output the operation signal P1 either, thereby ending the discharging of the filter capacitor 7.

As a result, if there is residual charge in the filter capacitor when the main circuit is stopped, the filter capacitor 7 can be automatically discharged using the overvoltage suppressing thyristor 8 and the overvoltage discharge resistor 9, and the filter capacitor can be discharged during inspection work. It is possible to eliminate the risk of electric shock due to the capacitor 7 being held at a high voltage.

Next, a vehicle power supply device according to a sixth embodiment of the present invention will be described with reference to FIGS. The feature of the sixth embodiment resides in that, in the main circuit configuration shown in FIG. 6, the protection operation circuit 15 is replaced by the same protection operation circuit 150 as that of the second embodiment shown in FIG.

The protection operation circuit 150 does not perform the forced discharge operation of the filter capacitor 7 unless the manual switch 18 is operated.

When the operator operates the manual switch 18 before the inspection when the main circuit is stopped and the closing signal S3 is input to the protection operation circuit 150, the overhead line voltage detector 1
Looking at the voltage detection signal S1 from S3 and the voltage detection signal S2 from the filter capacitor voltage detector 14, if the filter capacitor voltage is 0, the AND circuit 16 does not output the operation signal P1. However, when the electric charge remains in the filter capacitor 7 and the signal S2 with voltage is input from the filter capacitor voltage detector 14, the indicator lamp 17 lights to indicate that the filter capacitor 7 has not been discharged. The AND circuit 16 outputs the operation signal P1 to the overvoltage suppressing thyristor 8 to turn it on,
The electric charge of the filter capacitor 7 is guided to the overvoltage discharging resistor 9 and consumed to reduce the voltage across the filter capacitor 7.

As a result, when the main circuit is stopped, the manual switch 1
When the operation of turning on 8 is performed, the filter capacitor 7 can be discharged by using the overvoltage suppressing thyristor 8 and the overvoltage discharging resistor 9, and the filter capacitor 7 is held at a high voltage at the time of inspection work, which causes an electric shock. It is possible to eliminate the danger.

Next, a vehicle power supply device according to a seventh embodiment of the present invention will be described with reference to FIGS. The vehicle power supply device of the seventh embodiment is characterized by having the main circuit configuration shown in FIG. 6 and the protection operation circuit 15 shown in FIG.
That is, the main circuit is not provided with a filter capacitor discharging contactor and a filter capacitor discharging resistor, and the filter capacitor discharging is performed by the switching element group of the inverter 6. Explaining the configuration, the high voltage DC of the overhead wire 1 is connected to an inverter 6 which is a power conversion circuit via a disconnector 2, a contactor 3, a filter reactor 4, and a semiconductor breaker 5, and a filter capacitor 7 provided in parallel therewith. The AC voltage is converted into a DC voltage by the inverter 6, and an AC voltage is output. In order to protect the inverter 6 against overvoltage, an overvoltage suppressing thyristor 8 and an overvoltage discharging resistor 9 are provided between the B contact side of the disconnector 2 and the ground point. A control circuit 120 is provided to control the operation of each part of these circuits, and the overhead wire voltage is supplied to the inverter 6 and the filter capacitor 7 via the disconnector 2, the contactor 3, the filter reactor 4, and the semiconductor breaker 5. The voltage is supplied and the switching control of the inverter 6 is performed to convert the voltage into a predetermined AC voltage and output the AC voltage.

Further, the control circuit 120 instantaneously turns on the overvoltage suppressing thyristor 8 to apply an overvoltage to the overvoltage discharging resistor 9 when the overhead wire voltage suddenly rises and the overvoltage is applied to the input end of the inverter 6. By conducting and consuming it, a protection operation of lowering the voltage of the filter capacitor 7 is performed. The control circuit 120 is provided with the protection operation circuit 15 having the configuration shown in FIG. 4, which is common to the third embodiment.

Next, the operation of the vehicle power supply device of the seventh embodiment will be described. During normal operation, the disconnector 2 is turned on and the control circuit 120 causes the contactor 3 and the semiconductor breaker 5 to operate.
Is supplied to supply the overhead line voltage to the filter capacitor 7 and the inverter 6, and the switching power of the inverter 6 is controlled to output the desired AC power from the inverter 6.

The control circuit 120 monitors the input voltage of the inverter 6, and upon detecting the overvoltage, immediately turns on the overvoltage suppressing thyristor 8 to guide the overvoltage to the overvoltage discharging resistor 9 to discharge the overvoltage, and the inverter 6 is discharged from the overvoltage. Protect.

When stopping the main circuit, the switching control of the inverter 6 is stopped and the semiconductor breaker 5 and the contactor 3 are turned off in accordance with a predetermined sequence. Then, the disconnector 2 is manually cut. When the disconnector 2 is turned off, its B contact is on.

In the protection operation circuit 15, the overhead line voltage detector 1
3 and the voltage detection signal S2 from the filter capacitor voltage detector 14 are input. Therefore,
If the overhead wire voltage is not applied and the filter capacitor voltage is also 0, the AND circuit 16 outputs the operation signal P1.
Is not output.

However, when the electric charge remains in the filter capacitor 7 and the signal S2 with voltage is input from the filter capacitor voltage detector 14, the indicator lamp 17 is turned on and the filter capacitor 7 is not discharged. At the same time, the AND circuit 16 outputs the operation signal P1 to the inverter 6 to operate it again, guides the charge of the filter capacitor 7 to the switching element group of the inverter 6 and consumes it, thereby lowering the voltage across the filter capacitor 7. .

As a result, if there is residual charge in the filter capacitor when the main circuit is stopped, the inverter 6 can be automatically restarted to discharge the filter capacitor 7, and the filter capacitor 7 remains at a high voltage during inspection work. The risk of electric shock being retained can be eliminated.

Next, a vehicle power supply device according to an eighth embodiment of the present invention will be described with reference to FIGS. The feature of the eighth embodiment resides in that, in the main circuit configuration shown in FIG. 6, the protection operation circuit 15 is replaced with the same protection operation circuit 150 as that of the fourth embodiment shown in FIG.

The protection operation circuit 150 does not perform the forced discharge operation of the filter capacitor 7 unless the manual switch 18 is operated. Further, when the main circuit is stopped, the operator operates the manual switch 18 prior to the inspection, and the closing signal S
When 3 is input to the protection operation circuit 150, the voltage detection signal S1 from the overhead wire voltage detector 13 and the voltage detection signal S2 from the filter capacitor voltage detector 14 are observed, and if the filter capacitor voltage is 0, AND circuit 16
The operation signal P1 is not output from 0. However, when the electric charge remains in the filter capacitor 7 and the signal S2 with voltage is input from the filter capacitor voltage detector 14, the indicator lamp 17 lights to indicate that the filter capacitor 7 has not been discharged. AND circuit 16
0 outputs the operation signal P1 to the inverter 6 to operate it again, guides the charge of the filter capacitor 7 to the switching element group of the inverter 6 and consumes it, thereby lowering the voltage across the filter capacitor 7.

As a result, when the main circuit is stopped, the manual switch 1
If the operation of turning on 8 is performed, the inverter 6 can be automatically re-operated to discharge the filter capacitor 7, and there is a risk that the filter capacitor 7 is held at a high voltage during an inspection work, resulting in electric shock. It can be lost.

[0082]

As described above, according to the first and fifth aspects of the present invention, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the power conversion circuit is supplied to the power conversion circuit. After monitoring the input voltage and detecting that the input voltage is not supplied, when the detection value of the detection voltage of both ends of the filter capacitor does not decrease, the discharge means should activate the protection switching element. Therefore, it is possible to consume the electric charge remaining in the filter capacitor with the protective resistor and prevent the filter capacitor from being held at a high voltage after the power conversion circuit is stopped.
You can eliminate the risk of electric shock during inspection work.

According to the second and sixth aspects of the invention, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the input voltage to the power conversion circuit is monitored, After detecting that the input voltage is not supplied, when the signal output means outputs the discharge command signal because the detection value of the detection means of the voltage across the filter capacitor is equal to or higher than the discharge setting value, Since the protection switching element is ignited by the discharging means, the electric charge remaining in the filter capacitor is consumed by the protection resistor so that the filter capacitor is not held at a high voltage after the power conversion circuit is stopped. It is possible to eliminate the risk of electric shock during inspection work.

According to the inventions of claims 3 and 7, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the input voltage to the power conversion circuit is monitored, After detecting that the input voltage is not supplied, when the detection value of the voltage across the filter capacitor does not decrease, the discharge device fires the plurality of switching elements. It is possible to dissipate the electric charge remaining in the power conversion circuit and prevent the filter capacitor from being held at a high voltage even after the power conversion circuit is stopped, thereby eliminating the risk of electric shock during inspection work.

According to the inventions of claims 4 and 8, when the operation of the power conversion circuit is stopped and the supply voltage to the power conversion circuit is cut off, the input voltage to the power conversion circuit is monitored, After detecting that the input voltage is not supplied, when the signal output means outputs the discharge command signal because the detection value of the detection means of the voltage across the filter capacitor is equal to or higher than the discharge setting value, Since multiple switching elements are ignited by the discharging means, the electric charge remaining in the filter capacitor should be consumed in the power conversion circuit so that the filter capacitor is not kept at a high voltage after the power conversion circuit is stopped. It is possible to eliminate the risk of electric shock during inspection work.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a main circuit according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a protection operation circuit used in the first embodiment.

FIG. 3 is a circuit diagram of a protection operation circuit used in a second embodiment of the present invention.

FIG. 4 is a circuit diagram of a protection operation circuit used in a third embodiment of the present invention.

FIG. 5 is a circuit diagram of a protection operation circuit used in a fourth embodiment of the present invention.

FIG. 6 is a circuit diagram of a main circuit according to a fifth embodiment of the present invention.

FIG. 7 is a circuit diagram of a conventional example.

[Explanation of symbols]

 1 Overhead Wire 2 Disconnector 3 Contactor 4 Filter Reactor 5 Semiconductor Circuit Breaker 6 Inverter 7 Filter Capacitor 8 Overvoltage Suppression Thyristor 9 Overvoltage Discharge Resistor 10 Filter Capacitor Discharge Contactor 11 Filter Capacitor Discharge Resistor 12 Control Circuit 13 Voltage Detection Device 14 voltage detector 15 protection operation circuit 16 AND circuit 17 indicator lamp 18 manual switch 120 control circuit 150 protection operation circuit 160 AND circuit

Claims (8)

[Claims] 1. A power converter circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power converter circuit, a filter capacitor connected in parallel to the filter capacitor, and a protection resistor and a protection switching device. An overvoltage protection circuit in which an element is connected in series, a filter capacitor discharge circuit connected in parallel with the filter capacitor, and a discharge resistor and a discharge contactor connected in series; A detection unit that detects the voltage across the capacitor, an overvoltage protection unit that fires the protection switching element when the detection value of the detection unit exceeds a predetermined overvoltage set value, and the power conversion circuit Control means for turning on the discharge contactor when the supply voltage to the power conversion circuit is cut off by stopping the operation; When the input voltage to the power conversion circuit is monitored and it is detected that the input voltage is not supplied to the power conversion circuit, the protection switching element is ignited when the detection value of the detection means does not decrease. A power supply device for a vehicle, which comprises: 2. A power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power conversion circuit, a filter resistor connected in parallel to the filter capacitor, and a protection resistor and a protection switching device. An overvoltage protection circuit in which an element is connected in series, a filter capacitor discharge circuit connected in parallel with the filter capacitor, and a discharge resistor and a discharge contactor connected in series; A detection unit that detects the voltage across the capacitor, an overvoltage protection unit that fires the protection switching element when the detection value of the detection unit exceeds a predetermined overvoltage set value, and the power conversion circuit Control means for turning on the discharge contactor when the supply voltage to the power conversion circuit is cut off by stopping the operation; A signal output unit that outputs a discharge command signal when the detected value of the output unit is equal to or greater than a predetermined discharge setting value, and monitors the input voltage to the power conversion circuit, and the input voltage to the power conversion circuit is A vehicle power supply device comprising: discharge means for igniting the protection switching element when the discharge command signal is output from the signal output means after detecting that the power is not being supplied. 3. A power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power conversion circuit, a discharge resistor and a discharge contact connected in parallel to the filter capacitor. Circuit for connecting a filter capacitor, which is connected in series with a detector, detecting means for detecting the voltage across the filter capacitor, and stopping the operation of the power conversion circuit to cut off the voltage supplied to the power conversion circuit. At this time, control means for turning on the discharge contactor, monitoring the input voltage to the power conversion circuit, after detecting that the input voltage is not supplied to the power conversion circuit, the detection means A vehicle power supply device comprising: a discharging unit that fires the plurality of switching elements when the detected value does not decrease. 4. A power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power conversion circuit, a discharge resistor and a discharge contact connected in parallel to the filter capacitor. Circuit for connecting a filter capacitor, which is connected in series with a detector, detecting means for detecting the voltage across the filter capacitor, and stopping the operation of the power conversion circuit to cut off the voltage supplied to the power conversion circuit. At this time, control means for turning on the discharge contactor, signal output means for outputting a discharge command signal when the detection value of the detection means is equal to or greater than a predetermined discharge setting value, and to the power conversion circuit Of the discharge command signal is output from the signal output means after detecting that the input voltage is not supplied to the power conversion circuit. And a discharge means for firing the plurality of switching elements while the vehicle power supply is in operation. 5. A power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power conversion circuit, a filter resistor connected in parallel to the filter capacitor, and a protection resistor and a protection switching device. An overvoltage protection circuit in which an element is connected in series, a detection means for detecting the voltage across the filter capacitor, and a protection value when the detection value of the detection means exceeds a predetermined overvoltage set value. Overvoltage protection means for firing the switching element for monitoring, the input voltage to the power conversion circuit is monitored, and after detecting that the input voltage is not supplied to the power conversion circuit, the detection value of the detection means is A power supply device for a vehicle, comprising: a discharge means for igniting the protection switching element when the voltage does not decrease. 6. A power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input terminal of the power conversion circuit, a protection resistor and a protection switching device connected in parallel to the filter capacitor. An overvoltage protection circuit in which an element is connected in series, a detection means for detecting the voltage across the filter capacitor, and a protection value when the detection value of the detection means exceeds a predetermined overvoltage set value. Means for activating the switching element for discharge, a signal output means for outputting a discharge command signal when the detection value of the detection means is equal to or more than a predetermined discharge set value, an input voltage to the power conversion circuit The discharge command signal from the signal output means after detecting that the input voltage is not supplied to the power conversion circuit. And a discharging means for igniting the protection switching element when the power is output. 7. A power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input end of the power conversion circuit, detection means for detecting a voltage across the filter capacitor, and the power conversion circuit. Discharge means for activating the plurality of switching elements when the detection value of the detection means does not decrease after monitoring that the input voltage is not supplied to the power conversion circuit by monitoring the input voltage to the power conversion circuit. A power supply device for a vehicle, comprising: 8. A power conversion circuit having a plurality of switching elements, a filter capacitor connected in parallel to an input end of the power conversion circuit, a detection unit that detects a voltage across the filter capacitor, and a detection unit of the detection unit. A signal output unit that outputs a discharge command signal when the detected value is equal to or greater than a preset discharge setting value, and monitors the input voltage to the power conversion circuit, and the input voltage is not supplied to the power conversion circuit. And a discharge means for igniting the plurality of switching elements when the discharge command signal is output from the signal output means.