CN214480274U - DC conversion circuit - Google Patents
DC conversion circuit Download PDFInfo
- Publication number
- CN214480274U CN214480274U CN202120856791.3U CN202120856791U CN214480274U CN 214480274 U CN214480274 U CN 214480274U CN 202120856791 U CN202120856791 U CN 202120856791U CN 214480274 U CN214480274 U CN 214480274U
- Authority
- CN
- China
- Prior art keywords
- circuit
- transistor
- voltage
- output
- capacitor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
Landscapes
- Dc-Dc Converters (AREA)
Abstract
The utility model provides a direct current conversion circuit, relates to circuit control technique, includes: the first and second booster circuits, the first and second resonant circuits and the control module; the first booster circuit is connected with the first end of the direct current power supply, and the second booster circuit is connected with the second end of the direct current power supply; the control module is respectively connected with a first transistor in the first booster circuit and a second transistor in the second booster circuit and controls the on-off states of the first transistor and the second transistor; the first resonance circuit and the second resonance circuit are respectively connected with the output ends of the first booster circuit and the second booster circuit; the first and second resonant circuits are respectively connected with the output circuit, and the converted electric energy is output through the first and second resonant circuits. The scheme provided by the disclosure enables the weight and the volume of the auxiliary power supply equipment to be reduced by using the high-frequency isolation transformer; and the low-voltage level IGBT and the soft switching technology are used, so that the overall power loss of the auxiliary power supply system is reduced.
Description
Technical Field
The present disclosure relates to circuit control technologies, and in particular, to a dc converter circuit.
Background
At present, an auxiliary power supply system is used as one of important electrical systems of the whole subway train, and a core device of the auxiliary power supply system is an auxiliary inverter circuit and a storage battery charger, and is responsible for supplying power to a passenger room air conditioner, a lighting device, a cooling fan, an air compressor, a passenger information and video monitoring system, a vehicle-mounted wireless communication device, a vehicle-mounted signal device, a storage battery (charging) and the like.
In the prior art, the auxiliary inverter circuit of the subway train adopts a power frequency auxiliary scheme, namely, the voltage of a direct-current contact network is sent into an IGBT inverter circuit through an input filter and a capacitor charging and discharging circuit, and is filtered by an output filter, a power frequency transformer is used for converting the voltage into 380V three-phase alternating current and 50Hz quasi-sine wave to supply power to load equipment.
However, the power frequency auxiliary scheme adopts the power frequency transformer, so that the transformer and the reactor have large volumes and heavy weights, and the auxiliary power supply equipment has large weight and volume. And the inverter circuit adopts the IGBT with 3300V voltage class, so that the whole power loss of the auxiliary power supply system is large.
SUMMERY OF THE UTILITY MODEL
The utility model provides a direct current conversion circuit, which aims to solve the problem that in the prior art, the auxiliary power supply equipment has larger weight and volume due to the adoption of a power frequency transformer, the large volume and heavy weight of the transformer and a reactor; and the inverter circuit adopts 3300V voltage level IGBT for the whole power loss of auxiliary power supply system is big problem.
According to a first aspect of the present application, there is provided a dc conversion circuit including: the device comprises a first booster circuit, a second booster circuit, a first resonant circuit, a second resonant circuit and a control module;
the first booster circuit is connected with the second booster circuit in series, the first booster circuit is connected with the first end of the direct-current power supply, and the second booster circuit is connected with the second end of the direct-current power supply; the control module is respectively connected with a first transistor in the first booster circuit and a second transistor in the second booster circuit and is used for controlling the on-off states of the first transistor and the second transistor; the first resonance circuit is connected with the output end of the first booster circuit, and the second resonance circuit is connected with the output end of the second booster circuit; the first resonant circuit and the second resonant circuit are respectively connected with the output circuit, and the electric energy converted from the direct-current power supply is output through the output circuit.
The present disclosure provides a direct current conversion circuit including: the device comprises a first booster circuit, a second booster circuit, a first resonant circuit, a second resonant circuit and a control module; the first booster circuit is connected with the second booster circuit in series, the first booster circuit is connected with the first end of the direct-current power supply, and the second booster circuit is connected with the second end of the direct-current power supply; the control module is respectively connected with a first transistor in the first booster circuit and a second transistor in the second booster circuit and is used for controlling the on-off states of the first transistor and the second transistor; the first resonance circuit is connected with the output end of the first booster circuit, and the second resonance circuit is connected with the output end of the second booster circuit; the first resonant circuit and the second resonant circuit are respectively connected with the output circuit, and the electric energy converted from the direct-current power supply is output through the output circuit. In the direct current conversion circuit provided by the disclosure, a high-frequency isolation transformer is used, so that the volume and weight of the transformer and the reactor are reduced, and the weight and volume of the auxiliary power supply equipment are reduced; the inverter circuit adopts low-voltage level IGBT and soft switching technology, so that the overall power loss of the auxiliary power supply system is reduced.
Drawings
Fig. 1 is a schematic structural diagram of a dc conversion circuit according to a first exemplary embodiment of the present application;
fig. 2 is a schematic structural diagram of a dc conversion circuit according to a second exemplary embodiment of the present application;
fig. 3(a) is a schematic diagram of a control process of a dc conversion circuit according to a first exemplary embodiment of the present application;
fig. 3(b) is a control schematic block diagram of a dc conversion circuit according to a first exemplary embodiment of the present application;
fig. 4 is a schematic structural diagram of a dc conversion circuit according to a third exemplary embodiment of the present application;
fig. 5 is a schematic diagram of an inverter circuit of the structural schematic diagram of the resonant circuit in the embodiment shown in fig. 4 shown in the first exemplary embodiment;
FIG. 6 is a schematic diagram of an inductive-capacitive resonant circuit illustrating a structural schematic of the resonant circuit in the embodiment of FIG. 4 in accordance with the first exemplary embodiment;
FIG. 7 is a schematic circuit diagram of a rectifier bridge of the structural schematic of the resonant circuit in the embodiment of FIG. 4 shown in the first exemplary embodiment;
fig. 8 is a schematic structural diagram of a dc conversion circuit according to a fourth exemplary embodiment of the present application.
Detailed Description
The auxiliary power supply system is one of important electrical systems of the whole subway train, and the core equipment of the auxiliary power supply system is an auxiliary inverter circuit and a storage battery charger, and is responsible for supplying power to a passenger room air conditioner, a lighting system, a cooling fan, an air compressor, a passenger information and video monitoring system, a vehicle-mounted wireless communication device, a vehicle-mounted signal device, a storage battery (charging) and the like. At present, the auxiliary inverter circuit of the subway train adopts a power frequency auxiliary scheme, namely, the voltage of a direct current contact network is sent into an IGBT inverter circuit through an input filter and a capacitor charging and discharging circuit, and is filtered by an output filter, a power frequency transformer is used for converting the voltage into 380V three-phase alternating current and 50Hz quasi-sine wave to supply power to load equipment.
However, the power frequency auxiliary scheme adopts a 50Hz power frequency transformer, which has large transformer and reactor volume and heavy weight, resulting in large weight and volume of the auxiliary power supply equipment. And the inverter circuit adopts the IGBT with 3300V voltage class, so that the whole power loss of the auxiliary power supply system is large.
In order to solve the technical problem, the scheme provided by the application comprises a direct current conversion circuit, a two-stage circuit structure is adopted, and a first stage adopts a series circuit structure, so that the input power voltage is divided into circuits connected in series, the voltage required to be borne by the circuit directly connected with the input power supply is reduced, and the withstand voltage grade of a transistor adopted in the first stage circuit structure can be reduced. Meanwhile, the voltage value input into the second-stage resonant circuit is reduced due to the adoption of a voltage division mode, and the withstand voltage grade of a transistor adopted in the second-stage circuit structure can be further reduced. Thereby reducing the energy loss generated in the transistor as a whole. The second-stage output adopts a parallel circuit structure, and can transmit the output voltage of each circuit to an output circuit, so that the electric energy obtained after the direct-current input power supply is converted is obtained.
Fig. 1 is a schematic structural diagram of a dc conversion circuit according to a first exemplary embodiment of the present application.
As shown in fig. 1, the structure of the dc conversion circuit provided in this embodiment includes: the circuit comprises a first booster circuit 11, a second booster circuit 12, a first resonant circuit 13, a second resonant circuit 14 and a control module 15.
The first booster circuit 11 and the second booster circuit 12 are connected in series, the first booster circuit 11 is connected to one end of the dc power supply, and the second booster circuit 12 is connected to the other end of the dc power supply.
Specifically, the first boost circuit 11 and the second boost circuit 12 are connected in series and coupled between the positive and negative poles of the dc power supply, and can divide the input voltage of the dc power supply. Thereby reducing the voltage levels required to be borne by the first booster circuit 11 and the second booster circuit 12. When the voltage level on the circuit is reduced, transistors having a low withstand voltage level may be provided in the first booster circuit 11 and the second booster circuit 12, and the power loss of the transistors may be reduced, thereby reducing the power loss of the auxiliary power supply system as a whole.
Further, transistors are provided in the first voltage boost circuit 11 and the second voltage boost circuit 12, a first transistor is provided in the first voltage boost circuit, and a second transistor is provided in the second voltage boost circuit.
In practical applications, the control module 15 may be connected to the first transistor in the first boost circuit 11 and the second transistor in the second boost circuit 12, and the control module 15 is configured to control the on/off states of the first transistor and the second transistor.
By controlling the switching states of the first transistor and the second transistor, the voltages input from the first booster circuit 11 and the second booster circuit 12 can be boosted. For example, the voltage of the dc input voltage is 1500V, if two voltage boosting circuits are provided, the voltage at the input end of each voltage boosting circuit is 750V, and each voltage boosting circuit outputs 1150V dc power after the voltage boosting processing by the voltage boosting circuits.
The first Transistor and the second Transistor have the same structure and are formed by an Insulated Gate Bipolar Transistor (IGBT) and a diode which are connected in parallel in an opposite direction. IGBTs belong to switching devices in circuits.
Specifically, the control module collects and analyzes related current and voltage values in the circuit and generates a first signal for driving the first transistor and a second signal for driving the second transistor, so that the first transistor and the second transistor are driven. The first and second signals may be in the form of duty cycles, whereby the first and second transistors may be controlled by the duty cycles. The control module may be, for example, a PWM controller, or may be implemented as a digital controller, such as a microcontroller and/or a digital signal processor, etc.
In this arrangement, if the dc power voltage input to the dc conversion circuit fluctuates in a wide range, the duty ratios of the first transistor and the second transistor can be adjusted by the control module, so as to adjust the output voltages of the first boost circuit and the second boost circuit, thereby meeting the requirement of adapting to the voltage fluctuation.
In the dc converter circuit, the first resonant circuit 13 is connected to the output terminal of the first booster circuit 11, and the second resonant circuit 14 is connected to the output terminal of the second booster circuit 12. The power output by the first boost circuit 11 and the second boost circuit 12 can be transmitted to the output circuit through the first resonant circuit 13 and the second resonant circuit 14 which are connected in parallel.
Specifically, the booster circuit converts a voltage input from the dc power supply, which fluctuates in a wide range, into a stable dc voltage, and takes the output stable dc voltage as an input to the resonant circuit.
For example, in practical application, the rated input voltage of the auxiliary DC power supply for the metro vehicle is DC1500V, and the DC voltage input voltage range is DC 1000V-DC 2000V. The direct current power supply inputs a first booster circuit 11 and a second booster circuit 12 which are connected in series, and the voltage value of each booster circuit is half of the direct current input voltage value; the boost circuits process the input DC voltage to obtain a stable output voltage, for example, the output voltage of each boost circuit can be set to DC 1150V. DC1150V was chosen because the output of the boost circuit is higher than the input voltage, again for the voltage class of the switching devices in the subsequent resonant circuit.
The first resonant circuit 13 and the second resonant circuit 14 are connected to an output circuit, respectively, and output electric energy converted from the dc power supply through the output circuit.
Specifically, the first resonant circuit and the second resonant circuit are connected in parallel to the output circuit, so that the electric energy output by the first boost circuit and the second boost circuit can be transmitted to the output circuit. For example, the output voltages of the first resonant circuit and the second resonant circuit can be set to DC 700V. The output voltage of the output circuit is also DC 700V.
In practical application, for the auxiliary power supply system of the subway vehicle, 700V direct current output by the output circuit can be used for supplying power to a direct current-alternating current inverter circuit at the rear stage, and then the power is filtered by an output filter and converted into 380V three-phase alternating current and 50Hz quasi-sine wave to supply power to load equipment.
The application provides a direct current conversion circuit, includes: the device comprises a first booster circuit, a second booster circuit, a first resonant circuit, a second resonant circuit and a control module; the first booster circuit is connected with the second booster circuit in series, the first booster circuit is connected with the first end of the direct-current power supply, and the second booster circuit is connected with the second end of the direct-current power supply; the control module is respectively connected with a first transistor in the first booster circuit and a second transistor in the second booster circuit and is used for controlling the on-off states of the first transistor and the second transistor; the first resonance circuit is connected with the output end of the first booster circuit, and the second resonance circuit is connected with the output end of the second booster circuit; the first resonant circuit and the second resonant circuit are respectively connected with the output circuit, and the electric energy converted from the direct-current power supply is output through the output circuit. The application provides a direct current conversion circuit adopts two-stage circuit structure, and the circuit topology structure that two boost circuit and two resonant circuit cluster go into and go out, first order are two boost circuit of series connection, and every boost circuit exports for a resonant circuit, and two resonant circuit are parallelly connected and are connected with output circuit, through the electric energy after output circuit output carries out the transform to DC power supply. The two serially connected booster circuits divide the input power supply voltage into the serially connected circuits, so that the voltage required to be borne by the circuit directly connected with the input power supply is reduced, the withstand voltage grade of the transistor adopted in the circuit structure can be reduced, and the overall power loss of the auxiliary power supply system is reduced.
In an alternative embodiment, the first boost circuit 11 and the second boost circuit 12 in fig. 1 are boost chopper circuits having the same structure. The Boost chopper circuit is also referred to as a Boost circuit. The boost chopper circuit is one of six basic chopper circuits, and is a switching direct current boost circuit, which can make the output voltage higher than the input voltage. The method is mainly applied to the transmission of a direct current motor, a single-phase power factor correction circuit and other alternating current and direct current power supplies.
Fig. 2 is a schematic structural diagram of a dc conversion circuit according to a second exemplary embodiment of the present application.
As shown in fig. 2, in the dc converter circuit provided in this embodiment, the first boost circuit 11 and the second boost circuit 12 have the same structure, and may specifically be boost chopper circuits, where the boost chopper circuits specifically include: an inductor 21, a filter capacitor 22, an energy storage capacitor 23, a transistor 24 and a diode 25; a first end of the filter capacitor 22 is connected with a first end of the inductor 21, a second end of the inductor 21 is connected with a first end of the transistor 24 and a first end of the diode 25 respectively, and a second end of the diode 25 is connected with a first end of the energy storage capacitor 23; a second terminal of the filter capacitor 22, a second terminal of the transistor 24, and a second terminal of the energy storage capacitor 23 are connected.
Note that since the circuit elements included in the first booster circuit 11 and the second booster circuit 12 are the same, they are denoted by the same reference numerals, and for example, inductors are provided in the first booster circuit 11 and the second booster circuit 12, and the inductor 21 is used for both the first booster circuit and the second booster circuit, which does not mean that the inductor 21 is shared by both the first booster circuit and the second booster circuit.
Two filter capacitors 22 in the two boost chopper circuits are connected in series between the positive and negative poles of the dc power supply. Namely, the voltage value of each filter capacitor is the voltage value of the boosting chopper circuit to which the filter capacitor belongs.
Specifically, for each boost chopper circuit, when the transistor 24 is turned on, the dc power supply, the inductor 21 in the first boost circuit 11, the transistor 24 in the first boost circuit 11, the inductor 21 in the second boost circuit 12, and the transistor 24 in the second boost circuit 12 form a loop so that the dc power supply charges the inductors 21 in the two boost circuits. For example, when the input voltage of the boost chopper circuit is 750V, the inductor 21 is charged with the 750V dc power, and energy is stored in the inductor 21.
When the transistor 24 is turned off, the dc power supply, the inductor 21 in the first voltage boost circuit 11, the diode 25 in the first voltage boost circuit 11, the energy storage capacitor 23 in the first voltage boost circuit 11, the inductor 21 in the second voltage boost circuit 12, the diode 25 in the second voltage boost circuit 12, and the energy storage capacitor 23 in the second voltage boost circuit 12 form a loop. The inductors 21 in both boost circuits are capable of generating a reverse induced voltage.
Meanwhile, since the conduction direction of the diode 25 is the direction from the inductor 21 to the energy storage capacitor 23, when the inductor 21 generates a reverse induction voltage, the diode 25 is turned on, so that the reverse induction voltage generated by the inductor 21 can be stored in the energy storage capacitor 23.
The electric energy in the energy storage capacitor 23 is output to the lower stage resonant circuit, and it is ensured that the voltage output to the lower stage resonant circuit is kept constant. By adjusting the duty ratio of the transistor 24, the current value of the inductor 21 when transmitting electric energy to the rear end can be controlled, and the energy transmitted from the inductor 21 to the energy storage capacitor 23 is further controlled, so that the voltage output from the energy storage capacitor 23 to the lower-stage resonant circuit can be guaranteed to be a constant value.
In an alternative embodiment, the boost chopper circuit boosts the input voltage, chops the regulated output voltage to DC1150V, and outputs it as an input to the resonant circuit of the next stage. Specifically, the output voltages of the two booster circuits are input to the first resonant circuit 13 and the second resonant circuit 14, respectively.
Fig. 3(a) is a schematic diagram of a control process of the dc conversion circuit according to the first exemplary embodiment of the present application.
As shown in fig. 3(a), in the dc conversion circuit provided in this embodiment, the first boost circuit includes a first inductor and a first filter capacitor, and the second boost circuit includes a second inductor and a second filter capacitor.
For example, referring to fig. 2, the first boost circuit 11 is provided with a first inductor 21 and a first filter capacitor 22, and the second boost circuit 12 is provided with a second inductor 21 and a second filter capacitor 22.
The control module can be connected with the first filter capacitor and used for collecting first voltage of the first filter capacitor, and the control module can be connected with the second filter capacitor and used for collecting second voltage of the second filter capacitor. The voltage of the first filter capacitor is the input voltage of the first booster circuit, and the voltage of the second filter capacitor is the input voltage of the second booster circuit. Therefore, the control module can acquire the input voltage values of the first booster circuit and the second booster circuit.
The control module can be further connected with the first inductor to acquire a first actual current of the first inductor, and the control module can be further connected with the second inductor to acquire a second actual current of the second inductor. The current on the first inductor is the current value in the first booster circuit, and the current on the second inductor is the current value in the second booster circuit. Therefore, the control module can acquire the current values in the first booster circuit and the second booster circuit.
The control module can be connected with the output circuit so as to collect the output voltage of the converted electric energy in the output circuit.
Specifically, the voltage and current values can be acquired through the sensor, and the acquired data is transmitted to the control module.
The control module may determine a first duty cycle of the first transistor and a second duty cycle of the second transistor based on the first voltage, the second voltage, the first actual current, the second actual current, the output voltage, and the reference voltage.
The control module may be arranged based on closed loop control logic known in the art, enabling it to adjust the duty cycle of the first and second transistors based on the collected data.
The reference voltage is a preset voltage value, and may be an output voltage converted by the dc conversion circuit in an ideal state. For example, the reference voltage may be DC 700V.
The control module controls the on-off state of the first transistor according to the first duty ratio, and the control module controls the on-off state of the second transistor according to the second duty ratio.
The specific control process of the control module comprises the following steps:
step 301, collecting a first voltage of a first filter capacitor, collecting a second voltage of a second filter capacitor, collecting a first actual current of a first inductor, and collecting a second actual current of a second inductor; and collecting the output voltage of the converted electric energy.
The control module of this application can gather the input voltage that two boost circuit shared, can also gather the current value in two boost circuit, can also gather whole DC conversion circuit's output voltage, and then can be according to the difference between output voltage and the reference voltage to and the input voltage that two boost circuit shared, the current value in two boost circuit, confirm the on-off state of the transistor in two boost circuit.
Specifically, a structural design of a current inner loop voltage outer loop double closed loop control system can be adopted. The direct current conversion circuit comprises two current inner rings which respectively regulate input currents of a first booster circuit and a second booster circuit, and a voltage outer ring ensures the output voltage of the direct current conversion circuit to be stable. Meanwhile, in order to ensure the balance of the input voltages of the two booster circuits, a grading ring control is added.
And 302, generating a voltage-sharing control variable according to the first voltage and the second voltage.
The two booster circuits can equally divide the input voltage, so that the voltage value borne by each booster circuit is minimum. In order to enable the two voltage boost circuits to share the input voltage of the dc power supply equally, a voltage-sharing control variable may be generated according to the first voltage and the second voltage, and the switching state of the transistor in the voltage boost circuit may be adjusted by the voltage-sharing control variable, so that the two voltage boost circuits share the voltage of the dc power supply equally.
Further, the control module may determine an input voltage difference according to the first voltage and the second voltage; and the control module performs proportional and integral processing on the input voltage difference value to obtain a voltage-sharing control variable.
Because in the circuit structure of the application, the two voltage boosting circuits are connected in series, and the two filter capacitors in the two voltage boosting circuits are connected in series between the positive electrode and the negative electrode of the direct current power supply, the voltage value shared by the two voltage boosting circuits can be obtained by detecting the first filter capacitor and the second filter capacitor which are connected in series. And then carrying out balance control on the midpoint voltage of the first capacitor and the second capacitor which are connected in series. Specifically, the input midpoint voltage can be adjusted by adjusting the inductor current in each of the boost circuits.
Specifically, the voltage difference between the sampled first filter capacitor and the sampled second filter capacitor can be made, and then the voltage difference is output as a voltage-sharing control variable of the first boost circuit and the second boost circuit through the PI regulator, and the voltage-sharing control variable can be used as a fine adjustment quantity of the inductor current reference value, that is, an adjustment quantity of the current reference value.
Specifically, the first voltage and the second voltage refer to input voltages of the first boost circuit and the second boost circuit, respectively, and it is assumed that the first voltage and the second voltage are input voltages of the first boost circuit and the second boost circuit, respectivelyIs v isin1And vin2，vin1And vin2And the difference value after difference comparison is the input voltage difference value. And the input voltage difference value enters a grading ring regulator, and a grading control variable is obtained through proportional and integral processing. Namely, obtaining the reference current value I of the first booster circuitBref1And a reference current value I of the second booster circuitBref2The fine adjustment amount of (3).
Step 303, determining a first duty ratio of the first transistor and a second duty ratio of the second transistor according to the voltage-sharing control variable, the first actual current, the second actual current, the output voltage and the reference voltage.
The reference voltage is a required output voltage, and the output voltage is a voltage actually output by the dc conversion circuit, so that a control amount for adjusting the transistor can be obtained by comparing the reference voltage with the output voltage. The voltage-sharing control variable is also a control quantity obtained based on voltage, reference values of currents in the two booster circuits can be obtained according to the two control quantities, the output voltage and the input voltages of the two booster circuits are control targets, the control targets cannot be directly controlled, the control targets can be indirectly achieved only through intermediate controllable control quantities, and the intermediate quantities are inductive currents in the two booster circuits, namely currents in the two booster circuits. Therefore, the reference value of the current in the two booster circuits can be obtained from the above two control amounts. And then, a first duty ratio of the first transistor and a second duty ratio of the second transistor can be determined according to the current reference values and the actual currents in the two booster circuits.
Further, the control module can determine a first reference current and a second reference current according to the output voltage, the reference voltage and the voltage-sharing control variable; the first reference current is a reference current corresponding to the first booster circuit, and the second reference current is a reference current corresponding to the second booster circuit.
The reference current respectively refers to a current value expected to flow through a first inductor in the first booster circuit and a current value expected to flow through a second inductor in the second booster circuit, and the current value actually flowing through the first booster circuit and the second booster circuit can be adjusted to the reference current value by adjusting the switching state of the transistor.
Specifically, in the scheme of the application, the voltage finally output by the direct current conversion circuit is controlled by controlling the current on the inductor. Specifically, when output voltage is low, the inductor current can be increased to increase the energy stored in the inductor to improve the energy stored in the energy storage capacitor, and further improve the voltage output by each booster circuit to improve the voltage output by the whole direct current conversion circuit, or vice versa, and the process can be completed by the PI controller.
The PI controller is used for realizing no-static tracking, and can realize target control, namely no-static tracking of output voltage by adjusting control quantity.
The control module determines a voltage control variable according to the output voltage and the reference voltage; further, the control module determines a bias voltage value according to the output voltage and the reference voltage; and the control module performs proportional integral processing on the bias pressure value to obtain a voltage control variable.
Specifically, the control module may compare the output voltage of the dc conversion circuit with a preset reference voltage, so as to determine the voltage control variable. The transistor is controlled based on the voltage control variable, and the voltage value output by the DC conversion circuit can be approximately the same as the reference voltage.
Further, the difference between the output voltage and the reference voltage can be calculated, so as to obtain a deviation voltage value between the output voltage and the reference voltage, and then the deviation voltage value is subjected to proportional-integral processing, so as to obtain a voltage control variable.
Further, the control module equally divides the voltage control variable to obtain the equally divided voltage control variable.
In the dc conversion circuit, the first stage of the boost circuit may be formed by connecting two boost circuits having the same structure in series, and the two boost circuits having the same structure may divide the voltage of the input dc power supply. Therefore, the obtained voltage control variables can be equally divided, and the two voltage boosting circuits are respectively controlled by the equally divided voltage control variables. For example, if the voltage controlled variable is u, the first booster circuit and the second booster circuit can be controlled by u/2.
Specifically, the current reference value of each boost circuit may be determined according to the equalized voltage control variable and the voltage-equalizing control variable. And determining a first reference current and a second reference current according to the equalized voltage control variable and the voltage-equalizing control variable.
Further, in order to enable the two voltage boost circuits to equally divide the input voltage, when the first voltage boost circuit and the second voltage boost circuit are controlled according to the equally divided voltage controlled variable and the voltage-sharing controlled variable, the difference value between the equally divided voltage controlled variable and the voltage-sharing controlled variable may be used as the first reference current, and the control module may use the sum of the equally divided voltage controlled variable and the voltage-sharing controlled variable as the second reference current.
The purpose of the equalizing ring control is to equalize the input voltages of the two booster circuits, so that the control module takes the difference value of the equalized voltage control variable and the equalizing control variable as a first reference current, and takes the sum of the equalized voltage control variable and the equalizing control variable as a second reference current. And the two booster circuits are controlled by using the obtained first reference current and second reference current.
The control module specifically determines a first duty ratio of the first transistor according to the first reference current and the first actual current; the control module determines a second duty ratio of the second transistor according to the second reference current and the second actual current.
Further, the control module obtains a first current deviation value according to the first reference current and the first actual current; the control module performs proportional and integral processing on the first current deviation value to determine a first duty ratio of the first transistor; and/or the control module obtains a second current deviation value according to the second reference current and the second actual current, and the control module performs proportional and integral processing on the second current deviation value to determine a second duty ratio of the second transistor.
The control module is used for controlling the on-off state of the transistor through the driving signal according to the obtained first duty ratio as the driving signal of the first transistor and the second duty ratio as the driving signal of the second transistor.
In step 304, the control module controls the on/off state of the first transistor according to the first duty ratio, and the control module controls the on/off state of the second transistor according to the second duty ratio.
Fig. 3(b) is a control schematic block diagram of the dc conversion circuit according to the first exemplary embodiment of the present application.
Specifically, as shown in fig. 3(b), the dc converter circuit outputs a voltage v by equalizing the power of the two voltage boosting circuits0And a reference voltage vorefComparing the reference values I of the two booster circuit inductive currents obtained after the voltage regulator and the power are equally dividedBref1，IBref2With respective actual currents IB1、IB2Comparing, and respectively passing through current regulator to obtain transistor control signals d in the first and second voltage boost circuits1，d2(ii) a Namely a first duty cycle and a second duty cycle.
Wherein: k1As a voltage loop sampling coefficient, K2Sampling a parameter for the current loop, K3Is the equalizer ring sampling coefficient. In the actual circuit, the sampling circuit has a modulation ratio, the larger current voltage is reduced to a smaller current voltage signal, and the original corresponding actual value can be restored by multiplying a set value in the control program.
Wherein, 1/sC is a transfer function of a controlled object of the voltage loop and also represents the corresponding impedance of the output capacitor C in the output circuit in a complex frequency domain. d1，d2The first duty cycle and the second duty cycle are respectively duty cycles for controlling the switching states of the transistors in the two booster circuits. Gid1(s)、Gid2(s) are each d1，d2Actual current I to the first and second boost circuitsB1、IB2I.e. the first actual current IB1Second actual current IB2The transfer function of (2). I isBref1，IBref2Is IB1、IB2Of (2), wherein IBref1Is a first reference current, IBref2Is a second reference current. Giod1(s)、Giod2(s) are each d1，d2Output current I to the first resonant circuit and the second resonant circuitO1、IO2The transfer function of (2).
Transfer function Gidj(s) the expression is:
wherein j is 1, 2,
is an inductor L in the first booster circuitB1(or inductor L in second booster circuitB2) The internal resistance of (1); s is a transfer function Gidj(s) a variable in the complex frequency domain; u shapeB1Is the output voltage of the first booster circuit; u shapeB2Is the output voltage of the second boost circuit.
Inductor current i.e. actual current I of booster circuitBjTo the first booster circuit (or second booster circuit) output voltage UBjTransfer function of
The expression of (a) is:
wherein j is 1, 2, d1，d2The duty ratios for controlling the switching states of the transistors in the two booster circuits are respectively a first duty ratio and a second duty ratio; s is a transfer function
A variable in the complex frequency domain; cB1The output capacitor of the first booster circuit; cB2The output capacitor of the second booster circuit; rB1A load resistor of the first booster circuit; rB2Is the load resistance of the second boost circuit.
Thus, a transfer function G can be obtainediodjThe expression of(s) is:
wherein R isLIs the load resistance of the output circuit.
The first resonant circuit and the second resonant circuit are resonant circuit structures with the same structure.
Fig. 4 is a schematic structural diagram of a dc conversion circuit according to a third exemplary embodiment of the present application.
The first resonance circuit 13 and the second resonance circuit 14 in fig. 1 have the same resonance circuit structure. As shown in fig. 4, the resonant circuit structure provided in this embodiment includes: an inverter circuit 41, an inductor-capacitor resonant circuit 42, and a rectifier bridge circuit 43.
The output end of the inverter circuit 41 is connected with the input end of the inductor-capacitor resonant circuit 42;
the output end of the inductor-capacitor resonant circuit 42 is connected with the input end of the rectifier bridge circuit 43;
wherein, the input end of the inverter circuit 41 is connected with the output end of the first booster circuit 11 or the output end of the second booster circuit 12;
the output terminal of the rectifier bridge circuit 43 is connected to the output circuit.
Wherein, two resonant circuit are the same resonant circuit structure of structure. The output end of the first booster circuit is connected with the input end of the first resonance circuit, and the output end of the second booster circuit is connected with the input end of the second resonance circuit. The output ends of the two resonant circuits are connected in parallel and are respectively connected with the output circuit.
Fig. 5 is a schematic diagram of an inverter circuit of the resonant circuit in the embodiment shown in fig. 4 according to the first exemplary embodiment.
In the resonance circuit, the inverter circuit includes:
a first group of transistors 411, a second group of transistors 412;
the first group of transistors 411 includes a third transistor 51 and a fourth transistor 52 connected in series, and the second group of transistors 412 includes a fifth transistor 53 and a sixth transistor 54 connected in series; the third transistor 51 and the fifth transistor 53 are turned on simultaneously, and the fourth transistor 52 and the sixth transistor 54 are turned on simultaneously.
When the third transistor 51 and the fifth transistor 53 are turned on simultaneously, the electric energy flows out from the positive electrode output end of the booster circuit, passes through the third transistor 51, the inductor-capacitor resonant circuit 42 and the fifth transistor 53, and returns to the negative electrode of the booster circuit. When the fourth transistor 52 and the sixth transistor 54 are turned on simultaneously, the electric energy flows from the positive output terminal of the voltage boosting circuit, passes through the sixth transistor 54, the inductor-capacitor resonant circuit 42 and the fourth transistor 52, and returns to the negative electrode of the voltage boosting circuit.
The first set of transistors 411 is connected in parallel with the second set of transistors 412.
Since the first resonant circuit 13 and the second resonant circuit 14 have the same resonant circuit configuration and the inverter circuit 41 is a component of the first resonant circuit 13 and the second resonant circuit 14, the circuit elements included therein are the same and are denoted by the same reference numerals. For example, the inverter circuit 41 is provided in each of the first resonant circuit 13 and the second resonant circuit 14, the transistors are provided in each of the inverter circuits 41, and the reference numeral 51 is used for the third transistor in each of the two resonant circuits, which does not indicate that the third transistor 51 is shared by the two resonant circuits, nor that the inverter circuit 41 is shared by the two resonant circuits. This description is also applicable to other circuit components in the first resonant circuit 13 and the second resonant circuit 14, and is not repeated.
Specifically, the inverter circuit is a single-phase full-bridge inverter circuit. The inverter circuit is composed of four transistors with the same structure. The direct current may be converted to alternating current by an inverter circuit. The switching frequency of the two sets of transistors, i.e. the switching frequency of the transistors, is the frequency of the output alternating current. For example, the first resonant circuit and the second resonant circuit have eight transistors in total, and the eight transistors have the same structure and the same switching frequency.
One end of the inductor-capacitor resonant circuit 42 is connected to a common node of the third transistor 51 and the fourth transistor 52, and the other end of the inductor-capacitor resonant circuit 42 is connected to a common node of the fifth transistor 53 and the sixth transistor 54.
The alternating current output from the inverter circuit 41 is used as an input to the inductor-capacitor resonant circuit 42. The frequency of the alternating current is the operating frequency of the resonant circuit.
Fig. 6 is a schematic diagram of an inductor-capacitor resonant circuit illustrating a structural schematic diagram of the resonant circuit in the embodiment shown in fig. 4 in the first exemplary embodiment.
In the resonance circuit, an inductor-capacitor resonance circuit includes:
a first capacitor 421, an isolation transformer 422;
a first capacitor 421 is connected in series with the primary side of the isolation transformer 422.
Further, the inductor-capacitor resonant circuit comprises two functions: a resonant circuit function and a high frequency isolation transformer function. Wherein the resonant circuit function is formed by primary inductance L of high-frequency isolation transformer TR1 (or TR2)r1(or L)r2) And an excitation inductor Lm1(or L)m2) And a resonance capacitor Cs1(or C)s2) And (4) the components are combined together. Resonant capacitor Cs1I.e. the first capacitor of the first resonant circuit, the resonant capacitor Cs2I.e. the second capacitance of the second resonant circuit.
The resonant frequency is determined by the circuit parameters of the whole machine and is a fixed value. The resonant frequency can be changed by changing the primary inductance L of the high-frequency isolation transformer TR1 (or TR2)r1(or L)r2) And a resonance capacitor Cs1(or C)s2) Is modified.
For example, in practical applications, the resonant frequency may be selected to be slightly greater than 20kHz, and the operating frequency may be slightly less than the resonant frequency or greater than 20 kHz. The larger the resonant frequency, the larger the operating frequency of the resonant circuit, i.e. the switching frequency of the transistors, and the larger the power loss, the lower the efficiency of the circuit, but the size and weight of the high frequency transformer and reactor will be reduced accordingly. Different transistor switching devices also have an effect on power loss. Therefore, the resonant frequency value and the resonant circuit working frequency value can be comprehensively considered and selected according to the design requirements in the actual circuit design process.
In addition, when the switching frequency of the transistor reaches 20kHz, the transistor is not audible to human ears. Therefore, the scheme provided by the application can reduce electromagnetic noise.
Fig. 7 is a schematic circuit diagram of a rectifier bridge of the structural schematic diagram of the resonant circuit in the embodiment shown in fig. 4 shown in the first exemplary embodiment.
In the resonance circuit, a rectifier bridge circuit includes:
a first set of diodes 431, a second set of diodes 432; the first set of diodes 431 is in parallel with the second set of diodes 432; the first group of diodes 431 includes a first diode 71 and a second diode 72 connected in series, and the second group of diodes 432 includes a third diode 73 and a fourth diode 74 connected in series;
the rectifier bridge circuit is a single-phase uncontrollable rectifier bridge circuit. The rectifier bridge circuit 43 is composed of 4 diodes with the same structure. The rectifier bridge circuit 43 converts the ac power transmitted from the inductor-capacitor resonant circuit 42 into dc power, and outputs the converted dc power through the output circuit.
Referring to fig. 6 and 7, one end of the secondary side of the isolation transformer 422 is connected to the common node of the first diode 71 and the second diode 72, and the other end of the secondary side of the isolation transformer 422 is connected to the common node of the third diode 73 and the fourth diode 74.
Specifically, the output terminal of the inductor-capacitor resonant circuit 42 is connected to the input terminal of the rectifier bridge circuit 43.
In practical application, the working frequency of the resonant circuit is slightly lower than the resonant frequency, so that the primary side excitation current of the high-frequency isolation transformer rises to the resonant current before the transistor switch in the inverter circuit acts, the secondary side current of the high-frequency isolation transformer is reduced to zero, and the diode in the rectifying circuit 43 is turned off at zero current. And meanwhile, the dead time of the IGBT in the inverter circuit is adjusted so that the resonant current can sufficiently discharge the parasitic capacitance connected in parallel with the IGBT, and the IGBT is switched on within the follow current time of the resonant current passing through the IGBT reverse diode, so that zero voltage switching-on is realized.
The power loss of the transistor in the whole direct current conversion circuit exceeds half of the power loss of the whole direct current conversion circuit. The power loss of the transistor comprises an on loss, an on loss and an off loss, wherein the most power loss is the on loss. The transistor is turned on, turned on and turned off once, so that the transistor is correspondingly turned on and turned off once, and accordingly, the higher the switching frequency of the transistor is, the higher the power loss is, the higher the heat generated by the corresponding transistor is, and the transistor is damaged when the generated heat reaches a certain degree. The power loss of all diodes in the whole dc conversion circuit also accounts for a large part of the power loss of the whole dc conversion circuit. The power loss of the diode comprises on-state loss and reverse recovery loss, and the two losses are equivalent in size.
The method provided by the application realizes zero-voltage switching-on of the transistor, so that the switching-on loss of the transistor can be reduced to be ignored; zero current turn-off of a secondary side rectifier bridge diode of the high-frequency isolation transformer is realized, and the reverse recovery loss of the rectifier bridge diode is reduced to be negligible. Through the two aspects, the power loss of the whole direct current conversion circuit can be effectively reduced.
Fig. 8 is a schematic structural diagram of a dc conversion circuit according to a fourth exemplary embodiment of the present application.
On the basis of the embodiment shown in fig. 1, the output circuit comprises an output capacitor 81;
the positive pole of the output end of the first resonant circuit 13 is connected with the first end of the output capacitor 81, and the negative pole of the output end of the first resonant circuit 13 is connected with the second end of the output capacitor 81;
the positive pole of the output terminal of the second resonant circuit 14 is connected to the first terminal of the output capacitor 81, and the negative pole of the output terminal of the second resonant circuit 14 is connected to the second terminal of the output capacitor 81.
Specifically, the output end 13 of the first resonant circuit, the output end of the second resonant circuit 14, and the output capacitor 81 are connected in parallel. Namely, the outputs of the two resonant circuits are connected in parallel and filtered by a filter capacitor C of the output circuit to output DC700V DC voltage, which is supplied to the lower-stage DC load.
Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.
Claims (10)
1. A dc conversion circuit, comprising: the device comprises a first booster circuit, a second booster circuit, a first resonant circuit, a second resonant circuit and a control module;
the first booster circuit is connected with the second booster circuit in series, the first booster circuit is connected with a first end of a direct current power supply, and the second booster circuit is connected with a second end of the direct current power supply;
the control module is connected with a first transistor in the first booster circuit and a second transistor in the second booster circuit respectively, and is used for controlling the switching states of the first transistor and the second transistor;
the first resonant circuit is connected with the output end of the first booster circuit, and the second resonant circuit is connected with the output end of the second booster circuit;
the first resonant circuit and the second resonant circuit are respectively connected with an output circuit, and the electric energy converted by the direct-current power supply is output through the output circuit.
2. The dc converter circuit according to claim 1, wherein the first boost circuit and the second boost circuit are boost chopper circuits having the same configuration.
3. The direct current conversion circuit according to claim 2, wherein the boost chopper circuit comprises an inductor, a filter capacitor, an energy storage capacitor, a transistor, a diode;
the first end of the filter capacitor is connected with the first end of the inductor, the second end of the inductor is respectively connected with the first end of the transistor and the first end of the diode, and the second end of the diode is connected with the first end of the energy storage capacitor;
the second end of the filter capacitor, the second end of the transistor and the second end of the energy storage capacitor are connected;
two filter capacitors in the two boost chopper circuits are connected in series between the positive electrode and the negative electrode of the direct-current power supply.
4. The dc converter circuit according to claim 1, wherein the first boost circuit comprises a first inductor and a first filter capacitor, and the second boost circuit comprises a second inductor and a second filter capacitor;
the control module is connected with the first filter capacitor and used for collecting first voltage of the first filter capacitor, and the control module is connected with the second filter capacitor and used for collecting second voltage of the second filter capacitor; the voltage of the first filter capacitor is the input voltage of the first booster circuit, and the voltage of the second filter capacitor is the input voltage of the second booster circuit;
the control module is connected with the first inductor and used for collecting a first actual current of the first inductor, and the control module is connected with the second inductor and used for collecting a second actual current of the second inductor;
the control module is connected with the output circuit and used for collecting the output voltage of the converted electric energy;
the control module is used for determining a first duty ratio of the first transistor and a second duty ratio of the second transistor according to the first voltage, the second voltage, the first actual current, the second actual current, the output voltage and a reference voltage;
the control module is used for controlling the switching state of the first transistor according to the first duty ratio, and the control module is used for controlling the switching state of the second transistor according to the second duty ratio.
5. The dc converter circuit according to claim 1, wherein the first resonant circuit and the second resonant circuit have a same resonant circuit structure.
6. The dc conversion circuit of claim 5, wherein the resonant circuit structure comprises:
the inverter circuit, the inductance-capacitance resonance circuit and the rectifier bridge circuit;
the output end of the inverter circuit is connected with the input end of the inductance-capacitance resonance circuit;
the output end of the inductance-capacitance resonance circuit is connected with the input end of the rectifier bridge circuit;
the input end of the inverter circuit is connected with the output end of the first booster circuit or the output end of the second booster circuit;
and the output end of the rectifier bridge circuit is connected with the output circuit.
7. The DC conversion circuit according to claim 6, wherein the inverter circuit comprises a first group of transistors and a second group of transistors;
the first group of transistors includes a third transistor and a fourth transistor connected in series, and the second group of transistors includes a fifth transistor and a sixth transistor connected in series; wherein the third transistor and the fifth transistor are turned on at the same time, and the fourth transistor and the sixth transistor are turned on at the same time;
the first group of transistors and the second group of transistors are connected in parallel, one end of the inductor-capacitor resonance circuit is connected to a common node of the third transistor and the fourth transistor, and the other end of the inductor-capacitor resonance circuit is connected to a common node of the fifth transistor and the sixth transistor.
8. The dc conversion circuit of claim 6, wherein the inductor-capacitor resonant circuit comprises: a first capacitor, an isolation transformer;
the first capacitor is connected in series with the primary side of the isolation transformer.
9. The dc conversion circuit of claim 6, wherein the rectifier bridge circuit comprises: a first group of diodes, a second group of diodes; the first set of diodes is connected in parallel with the second set of diodes;
the first group of diodes comprises a first diode and a second diode connected in series, and the second group of diodes comprises a third diode and a fourth diode connected in series;
the inductance-capacitance resonant circuit comprises an isolation transformer, one end of a secondary side of the isolation transformer is connected to a common node of the first diode and the second diode, and the other end of the secondary side of the isolation transformer is connected to a common node of the third diode and the fourth diode.
10. The dc conversion circuit according to any one of claims 1 to 9, wherein the output circuit includes an output capacitor;
the positive electrode of the output end of the first resonant circuit is connected with the first end of the output capacitor, and the negative electrode of the output end of the first resonant circuit is connected with the second end of the output capacitor;
and the positive pole of the output end of the second resonant circuit is connected with the first end of the output capacitor, and the negative pole of the output end of the second resonant circuit is connected with the second end of the output capacitor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120856791.3U CN214480274U (en) | 2021-04-23 | 2021-04-23 | DC conversion circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120856791.3U CN214480274U (en) | 2021-04-23 | 2021-04-23 | DC conversion circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN214480274U true CN214480274U (en) | 2021-10-22 |
Family
ID=78180153
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202120856791.3U Active CN214480274U (en) | 2021-04-23 | 2021-04-23 | DC conversion circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN214480274U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114465511A (en) * | 2022-01-17 | 2022-05-10 | 富士电机（珠海）有限公司 | Induction furnace and IGBT power supply for induction furnace |
| CN117614268A (en) * | 2024-01-18 | 2024-02-27 | 荣耀终端有限公司 | Power management circuit, power management chip and electronic equipment |
-
2021
- 2021-04-23 CN CN202120856791.3U patent/CN214480274U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114465511A (en) * | 2022-01-17 | 2022-05-10 | 富士电机（珠海）有限公司 | Induction furnace and IGBT power supply for induction furnace |
| CN114465511B (en) * | 2022-01-17 | 2022-12-13 | 富士电机（珠海）有限公司 | Induction furnace and IGBT power supply for induction furnace |
| CN117614268A (en) * | 2024-01-18 | 2024-02-27 | 荣耀终端有限公司 | Power management circuit, power management chip and electronic equipment |
| CN117614268B (en) * | 2024-01-18 | 2024-05-10 | 荣耀终端有限公司 | Power management circuit, power management chip and electronic equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Liu et al. | A three-phase single-stage AC–DC wireless-power-transfer converter with power factor correction and bus voltage control | |
| CN103227575A (en) | Three-phase soft-switched PCF rectifiers | |
| CN108879895B (en) | Electric automobile energy transmission system and transmission method | |
| CN112928919B (en) | Isolated high-frequency resonant DC-DC converter with wide output voltage range and method | |
| US11518246B2 (en) | Electric drive system, powertrain, and electric vehicle | |
| CN111660844B (en) | Three-phase integrated vehicle-mounted charging system of plug-in electric automobile | |
| CN214480274U (en) | DC conversion circuit | |
| CN108923663A (en) | Single-phase bipolar AC-AC converter topology structure and its modulator approach | |
| CN111049182A (en) | Five-level common-ground type single-phase non-isolated photovoltaic grid-connected inverter circuit and modulation method thereof | |
| KR102371910B1 (en) | Dc-dc converter | |
| Tawfik et al. | Single-stage isolated DC/AC converter with continuous dynamic model and controller design | |
| CN114157150B (en) | High-gain bidirectional Y source-LLC isolated DC-DC converter | |
| CN111628556A (en) | Control strategy for improving DCDC efficiency of charging station based on energy router | |
| CN108565990B (en) | Wireless power transmission device with constant current output characteristic | |
| CN107769599B (en) | Forward five-level inverter based on switched capacitor | |
| CN107171563B (en) | The combined converter of tight adjustment output | |
| CN110061523B (en) | Multifunctional single-phase grid-connected inversion system and method with novel topological structure | |
| US11791739B2 (en) | AC-AC converter | |
| CN108270356B (en) | Direct-current distribution network energy router based on PWM/diode hybrid rectification structure and control method thereof | |
| CN216216584U (en) | Buck-boost inverter | |
| CN111740603A (en) | Soft-switch isolation DC-DC converter for auxiliary power supply of train | |
| CN112436747B (en) | Electric drive system, power assembly and electric automobile | |
| CN115833598A (en) | Input indirect series output parallel variable frequency modulation direct current converter topology and control method thereof | |
| CN115549254A (en) | Half-bridge drive-based wireless power transmission control system and method | |
| Ganne et al. | Performance of Single-Stage and Dual-Stage EV Battery Chargers for G2V and V2G Operation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |