JP2022165252A - Electric power conversion device - Google Patents

Abstract

To provide an electric power conversion device which can reduce a loss at the time of a power supply to a bi-direction.SOLUTION: In an electric power conversion device which can supply a power to a bi-direction, a control part makes a chopper circuit that is operated at the time of supplying a power of a first direction and a chopper circuit that is operated at the time of supplying the power of a second direction be different, and makes the number of chopper circuits that is operated at the time of supplying the power of the first direction and the number of chopper circuits that is operated at the time of supplying the power of the second direction be different, in the case where a power supply amount of the first direction and a power supply amount of the second direction are different.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a power conversion device capable of bidirectional power supply.

A chopper circuit is known as a circuit that converts a DC voltage into a different DC voltage. 2 and a reverse coupling reactor used as a phase reactor (see Patent Document 1, for example).

JP 2012-124977 A

However, by using a reactor magnetically coupled to a plurality of chopper circuits connected in parallel, a plurality of chopper circuits must always be operated. Therefore, if the power to be transmitted is different when transmitting power from a high voltage to a low voltage and when transmitting power from a low voltage to a high voltage, there is a problem that loss increases more than necessary in the direction of power transmission where the power is small. was there.

The present disclosure has been made in order to solve the above problems, and in particular, when the amount of power supplied in each direction is different, the number of circuits that operate depending on the direction of power supply is different. An object of the present invention is to provide a power conversion device capable of reducing loss during power supply.

A power conversion device according to the present disclosure is a power conversion device capable of bidirectional power supply, includes a plurality of chopper circuits, and a control unit that controls the chopper circuits, and supplies power in a first direction. and the amount of power supplied in the second direction are different, the control unit operates different chopper circuits when power is supplied in the first direction and when power is supplied in the second direction, and operates the first chopper circuit The number of chopper circuits operated when power is supplied in one direction is made different from the number of chopper circuits operated when power is supplied in the second direction.

According to the power conversion device of the present disclosure, it is possible to reduce loss during bidirectional power supply.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the power converter device which concerns on Embodiment 1 of this indication. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the power converter device which concerns on Embodiment 1 of this indication. It is a figure which shows the hardware configuration of the power converter device which concerns on Embodiment 1 of this indication. FIG. 4 is a diagram showing an example of waveforms of components when the power conversion device according to the first embodiment of the present disclosure is supplying power; FIG. 4 is a diagram showing an example of waveforms of components when the power conversion device according to the first embodiment of the present disclosure is supplying power; It is a figure which shows the modification of a structure of the power converter device which concerns on Embodiment 1 of this indication. It is a figure which shows the modification of a structure of the power converter device which concerns on Embodiment 1 of this indication. It is a figure which shows the modification of a structure of the power converter device which concerns on Embodiment 1 of this indication.

Description will be made below with reference to the drawings. It should be noted that the drawings are shown schematically, and the configuration is omitted or simplified for convenience of explanation. In addition, in the description given below, the same components are denoted by the same reference numerals, and their names and functions are also the same. Therefore, a detailed description thereof may be omitted to avoid duplication.

Embodiment 1.
FIG. 1 is a diagram showing the configuration of a power converter 1. As shown in FIG. As shown in FIG. 1, the power conversion device 1 of Embodiment 1 of the present disclosure includes a chopper circuit unit 10 that converts DC voltage into different DC voltages, a first capacitor 113, and a second capacitor 114. , provided. Electrolytic capacitors, for example, are used for the first capacitor 113 and the second capacitor 114 .

The chopper circuit unit 10 of the present disclosure is connected to a first power supply 120 and a second power supply 119, converts the DC voltage of the first power supply 120 into power of a different DC voltage, and supplies power to the second power supply 119. Output. The direction of power supply in which the DC voltage of the first power supply 120 is converted into power of a different DC voltage and output to the second power supply 119 is hereinafter referred to as the first direction or boosting direction. The chopper circuit unit 10 also converts the DC voltage of the second power supply 119 into power of a different DC voltage and outputs the power to the first power supply 120 . The direction of power supply in which the DC voltage of the second power supply 119 is converted into power of a different DC voltage and output to the first power supply 120 in this manner is hereinafter referred to as the second direction or step-down direction. That is, the chopper circuit section 10 can bidirectionally supply power. The power conversion of this chopper circuit unit 10 is controlled by the control unit 109, for example.

The positive electrode of the first power source 120 is connected with the positive electrode of the first capacitor 113 , and the negative electrode of the first power source 120 is connected with the negative electrode of the first capacitor 113 . Also, the positive electrode of the second power source 119 is connected to the positive electrode of the second capacitor 114 , and the negative electrode of the second power source 119 is connected to the negative electrode of the second capacitor 114 .

The chopper circuit unit 10 will be further described with reference to FIG. FIG. 2 is a diagram showing the configuration of the power converter 1 of Embodiment 1. As shown in FIG. The chopper circuit section 10 includes a first reactor 107, a second reactor 108, a plurality of diodes 102, 104 and 105 having anode terminals and cathode terminals, and a plurality of semiconductor switching elements having positive and negative electrodes and control terminals. 101, 103, 106 and . And these constitute a first switching leg, a second switching leg and a third switching leg. IGBTs (Insulated Gate Bipolar Transistors) are used as the semiconductor switching elements 101, 103, and 106, and the positive electrode is the collector, the negative electrode is the emitter, and the control electrode is the gate.

The first switching leg is configured by serially connecting a first diode 102 provided on the upper arm side and a first semiconductor switching element 101 provided on the lower arm side. The first reactor 107 has one terminal connected to the first capacitor 113 and the other terminal connected to the intermediate connection point of the first switching leg. In other words, one terminal of the first reactor 107 is connected to the positive electrode side of the first capacitor 113, and the other terminal of the first reactor 107 is connected to the anode of the first diode 102 and the first semiconductor switching terminal. It is connected to the positive electrode side of the element 101 . A component including the first switching leg and the first reactor 107 is defined as a first chopper circuit.

The second switching leg is configured by serially connecting a second semiconductor switching element 106 provided on the upper arm side and a second diode 105 provided on the lower arm side. The second diode 105 has one terminal connected to the first capacitor 113 and the other terminal connected to the intermediate connection point of the second switching leg. In other words, one terminal of the second reactor 108 is connected to the positive electrode side of the first capacitor 113, and the other terminal of the second reactor 108 is connected to the negative electrode of the second semiconductor switching element 106 and the second terminal. It is connected to the cathode of diode 105 . A component consisting of the second switching leg and the second reactor 108 is defined as a second chopper circuit.

The third switching leg is configured by serially connecting a third diode 104 provided on the upper arm side and a third semiconductor switching element 103 provided on the lower arm side. The other terminal of the second diode 105 is also connected to the middle junction of the third switching leg. In other words, the other terminal of second reactor 108 is connected to the anode of third diode 104 and the positive electrode side of third semiconductor switching element 103 . A component including the third switching leg and the second reactor 108 is defined as a third chopper circuit. The second reactor 108 forming the third chopper circuit is also the second reactor 108 forming the second chopper circuit.

As described above, chopper circuit portion 10 includes a plurality of chopper circuits whose switching legs are connected in parallel with each other. Of these, the second chopper circuit and the third chopper circuit are connected in parallel with the second switching leg that constitutes the second chopper circuit and the third switching leg that constitutes the third chopper circuit. be. They are respectively connected to the same second reactor 108 and share the second reactor 108 . That is, one second reactor 108 is part of the configuration of the second chopper circuit and the third chopper circuit. Furthermore, the second reactor 108 is also a path through which current flows during operation of the second chopper circuit, and a path through which current flows during operation of the third chopper circuit. Also, this has a different meaning from a magnetic coupling of a plurality of objects. On the other hand, the first reactor 107 of the first chopper circuit is part of the configuration of the first chopper circuit, but not part of the configuration of the other second chopper circuit or the third chopper circuit. not That is, there is no first reactor 107 in the current path generated by the second chopper circuit operation. The first reactor 107 and the second reactor 108 are separate and not magnetically coupled.

Also, as can be seen from the above description, the first chopper circuit and the third chopper circuit have the same configuration, and the first chopper circuit and the third chopper circuit are connected in parallel. That is, it is the same as the configuration in which a plurality of first chopper circuits are connected. And the second chopper circuit is connected in parallel with the plurality of first chopper circuits. Strictly speaking, the second switching leg forming the second chopper circuit and the first switching leg forming the first chopper circuit are connected in parallel. Hereinafter, when the first chopper circuit and the third chopper circuit are described together, the first chopper circuit and the third chopper circuit are collectively referred to as the first chopper circuit (or the first (third) chopper circuit). chopper circuit).

When the rated power of the first (third) chopper circuit and the second chopper circuit is the same, the same rating is selected for the parts constituting each chopper circuit. On the other hand, if the rated powers of the first chopper circuit and the third chopper circuit are different, for example, the first reactor 107 constituting the first chopper circuit and the second reactor 107 constituting the third chopper circuit Different ratings than 108 are used. Furthermore, it is assumed that the second reactor 108 shared with the second chopper circuit and the first reactor 107 not shared have different ratings. The rating of the reactor is determined by the inductance value, the number of turns, the resistance value, etc. When the ratings are the same, these are the same. However, if it is desired to maximize the effect of shifting the phases of the triangular wave carrier 203 and the triangular wave carrier 208 by 180 degrees, which will be described later, it is assumed that the reactors 107 and 108 have the same rating.

Further, for each diode and each semiconductor element, when the rated power of the first (third) chopper circuit and the second chopper circuit is different, the parts are selected according to the rating. Also, when the rated currents of the first chopper circuit and the third chopper circuit are different, similarly, components matching the rated currents are selected. However, if it is desired to maximize the effect of shifting the phases of the triangular wave carrier 203 and the triangular wave carrier 208 by 180 degrees in the same manner as the reactor, it is assumed that each switching element and each diode have the same rating. .

In the first embodiment, there are two first (third) chopper circuits that convert the voltage of the first power supply 120 to the voltage of the second power supply 119, and the voltage of the second power supply 119 is converted to the first is connected to one of the second chopper circuits for power conversion to the voltage of the power supply 120 of . In the third chopper circuit and the second chopper circuit, strictly speaking, the second switching leg forming the second chopper circuit and the first switching leg forming the first chopper circuit are connected in parallel. there is This configuration assumes that the amount of power supplied in the first direction is greater than the amount of power supplied in the second direction. That is, when the amounts of power supplied in the first direction and the amount of power supplied in the second direction are different, the chopper circuit that operates when the power is supplied in the first direction and the chopper circuit that operates when the power is supplied in the second direction have different configurations. there is Also, the number of first (third) chopper circuits that operate when power is supplied in the first direction with a large amount of power supply and the number of second chopper circuits that operate when power is supplied in the second direction with a small amount of power supply The numbers assume different configurations. Furthermore, it is assumed that the number of chopper circuits operating in the first direction is greater than the number of chopper circuits operating in the second direction.

Next, operation of the power converter 1 will be described. As described above, the power converter 1 is controlled by the controller 109 .

The control unit 109 includes a voltage detection unit 115 that detects the voltage of the first capacitor 113, a current detection unit 116 that detects the current of the second reactor 108, and a current detection unit that detects the current of the first reactor 107. 117 and a voltage detection unit 118 that detects the voltage of the second capacitor 114 . Further, each drive signal 110, 111, 112 is sent to each switching element based on at least one or more pieces of information.

The drive signal to the first semiconductor switching element 101 is set to the first drive signal 110, the drive signal to the second semiconductor switching element 106 is set to the second drive signal 112, and the drive signal to the third semiconductor switching element 103 is used. The signal is assumed to be a third drive signal 111 . Each drive signal 110, 111, 112 turns on each corresponding semiconductor switching element when it is High, and turns off each semiconductor switching element when it is Low. The semiconductor switching elements 101 , 106 and 103 are controlled by switching on and off of these drive signals 110 , 111 and 112 .

FIG. 3 is a diagram showing a hardware configuration diagram of the power converter 1. As shown in FIG. A control unit 109 in the power converter 1 is composed of a processor 20 that controls the chopper circuit unit 10 and a storage device 30 thereof.

The storage device 30 includes a volatile storage device such as a random access memory and a non-volatile auxiliary storage device such as a flash memory (not shown).

Processor 20 executes a program input from storage device 30 . Since the storage device 30 comprises an auxiliary storage device and a volatile storage device, a program is input to the processor 20 from the auxiliary storage device via the volatile storage device. Further, the processor 20 may output data such as calculation results to the volatile storage device of the storage device 30, or may store the data in the auxiliary storage device via the volatile storage device.

Here, the case where power is supplied from the first power supply 120 to the second power supply 119 will be further described with reference to FIG. FIG. 4 is a diagram showing an example of waveforms of components when the power conversion device 1 is supplying power from the first power supply 120 to the second power supply 119. As shown in FIG.

The upper graph in FIG. 4 shows the waveform 202 of the voltage Vdc1 of the first power supply 120 and the voltage Vdc2 waveform 201 of the second power supply 119 . The four graphs in the middle of FIG. 4 show the triangular wave carrier 203 generated in the control unit 109, the waveform 204 of the command value Iref1 for driving the first semiconductor switching element 101, and the current IL1 of the first reactor 107. A waveform 205, a waveform 206 of the current IQ1 flowing through the first semiconductor switching element 101, and a waveform 207 of the current ID1 flowing through the first diode 102 are shown, respectively. The lower four graphs in FIG. 4 show the triangular wave carrier 208 generated in the control unit 109, the waveform 209 of the command value Iref3 for driving the third semiconductor switching element 103, and the current IL2 of the second reactor 108. A waveform 210, a waveform 211 of the current IQ3 flowing through the third semiconductor switching element 103, and a waveform 212 of the current ID3 flowing through the third diode 104 are shown. Also, in the example of FIG. 4, the triangular wave carrier 203 and the triangular wave carrier 208 are out of phase by 180 degrees.

The command value Iref1 for driving the first semiconductor switching element 101 and the command value Iref3 for driving the third semiconductor switching element 103 are appropriately processed in the control unit 109 to generate necessary command values. be. At that time, for example, the voltage detection unit 115 of the first capacitor 113, the current detection unit 116 of the second reactor 108, the current detection unit 117 of the first reactor 107, and the voltage detection unit 118 of the second capacitor 114 detect specified value is used.

For example, when the voltage of the second power supply 119 is to follow a certain target voltage, the voltage value of the second capacitor 114 detected by the voltage detection unit 118 is compared with the target voltage, and based on the result of the comparison, A current command value is generated by proportional-integral control. Then, this current command value is compared with the current value of the first reactor 107 detected by the current detection unit 117, and the first semiconductor switching element 101 is driven by proportional-integral control based on the compared value. A command value is generated for

A period A in FIG. 4 is a period in which the first drive signal 110 is High. That is, the first semiconductor switching element 101 is controlled to be ON. During this period A, current flows through the route of first capacitor 113 - first reactor 107 - first semiconductor switching element 101 - first capacitor 113 . However, part of the current flows through first power supply 120 - first reactor 107 - first semiconductor switching element 101 - first power supply 120 . At this time, the current in the first reactor 107 increases at a speed related to the voltage of the first power supply 120 .

Specifically, the amount of current increase in the first reactor 107 can be obtained by multiplying the voltage of the first power supply 120 by the period A and dividing the result by the inductance value of the first reactor 107 (first voltage of one power supply 120×time of period A/inductance of first reactor 107). Therefore, the higher the voltage of the first power supply 120, the greater the amount of current increase. Also, the longer the period A, the greater the amount of current increase. Then, the current flowing through the first reactor 107 is larger at the end of the period A than at the beginning of the period A.

A period B in FIG. 4 is a period in which the first drive signal 110 is Low. That is, the first semiconductor switching element 101 is controlled to be off. During this period B, current flows through first capacitor 113 - first reactor 107 - first diode 102 - second capacitor 114 - first capacitor 113 . However, part of the current passes through first power supply 120 - first reactor 107 - first diode 102 - second power supply 119 - first power supply 120 . At this time, the current ID1 of the first reactor 107 decreases at a speed related to the voltage difference between the first power supply 120 and the second power supply 119 .

Specifically, the amount of decrease in the current of the first reactor 107 is obtained by subtracting the voltage of the first power supply 120 from the voltage of the second power supply 119 and multiplying the time period B by the inductance of the first reactor 107. ((voltage of second power supply 119−voltage of first power supply 120)×time of period B/inductance of first reactor 107). Therefore, the larger the difference between the voltage of the second power supply 119 and the voltage of the first power supply 120, the larger the amount of current decrease. Also, the longer the period B, the greater the amount of current decrease. Furthermore, the smaller the inductance of the first reactor 107, the greater the amount of current reduction. At the beginning of the period B, more current flows through the second reactor 108 than at the end of the period B.

Thus, the current increased in the first reactor 107 during the period when the first semiconductor switching element 101 is turned on by the first drive signal 110 of the control unit 109 is changed to It flows to the second power supply 119 via the path described above. By being controlled in this way, current flows from the first power supply 120 to the second power supply 119, and power can be supplied.

A period C in FIG. 4 is a period in which the third drive signal 111 is High. That is, the third semiconductor switching element 103 is controlled to be ON. During this period C, the current flows through the route of first capacitor 113-second reactor 108-third semiconductor switching element 103-first capacitor 113. FIG. However, part of the current flows through first power supply 120 - second reactor 108 - third semiconductor switching element 103 - first power supply 120 . At this time, the current IL2 of the second reactor 108 increases at a speed related to the voltage of the second power supply 119.

Specifically, the current increase amount of the second reactor 108 can be obtained by multiplying the voltage of the first power supply 120 by the period C and dividing the result by the inductance value of the second reactor 108 (second voltage of one power supply 120×time of period C/inductance of second reactor 108). Therefore, the higher the voltage of the first power supply 120, the greater the amount of current increase. Also, the longer the period C, the greater the amount of current increase. Then, more current flows through the second reactor 108 at the end of the period C than at the beginning of the period C.

A period D in FIG. 4 is a period in which the third drive signal 111 is Low. That is, the third semiconductor switching element 103 is controlled to be off. During this period D, current flows through first capacitor 113 - second reactor 108 - third diode 104 - second capacitor 114 - first capacitor 113 . However, part of the current passes through first power supply 120 - second reactor 108 - third diode 104 - second power supply 119 - first power supply 120 . At this time, the current in second reactor 108 decreases at a rate related to the voltage difference between first power supply 120 and second power supply 119 .

Specifically, the current decrease amount of the second reactor 108 is obtained by subtracting the voltage of the first power supply 120 from the voltage of the second power supply 119 and multiplying the time period C by the inductance of the second reactor 108. ((voltage of second power supply 119−voltage of first power supply 120)×time of period C/inductance of second reactor 108). Therefore, the larger the difference between the voltage of the second power supply 119 and the voltage of the first power supply 120, the larger the amount of current decrease. Also, the longer the period D, the greater the amount of current decrease. Then, more current flows through the second reactor 108 at the beginning of the period D than at the end of the period D. The greater the difference between the voltage of the second power supply 119 and the voltage of the first power supply 120, the longer the period during which the driving signals for the first semiconductor switching element 101 and the third semiconductor switching element 103 are High.

By controlling the third semiconductor switching element 103 by the third drive signal 111 of the control unit 109 in this way, current flows from the first power supply 120 to the second power supply 119, and power can be supplied. I can.

In the case of power supply in the first direction, the control unit 109 operates the first (third) chopper circuit with two circuits. Specifically, the first semiconductor switching element 101 and the third semiconductor switching element 103 are controlled by turning on and off corresponding drive signals by the control unit 109 with a phase shift of 180 degrees. By operating the two circuits in this manner, the sum of the current IL1 of the first reactor 107 and the current IL2 of the second reactor 108 flows through the first capacitor 113 . However, as described above, since the triangular wave carrier is shifted by 180 degrees, the increase/decrease in current is reduced. This is because by shifting the triangular wave carrier by 180 degrees, the increase/decrease in the current IL1 of the first reactor 107 and the current IL2 of the second reactor 108 are offset, and the increase/decrease cancels each other. Therefore, the current flowing into the first capacitor 113 can be reduced. Although this effect cannot be obtained if the triangular wave carriers are the same, it is possible to supply power from the first power supply 120 to the second power supply 119 . In this case, the timings of the driving signals for controlling the first semiconductor switching element 101 and the third semiconductor switching element 103 are the same. Also, in the case of power supply in the first direction, the second chopper circuit is not operated. That is, the drive signal 112 for the second semiconductor switching element 106 is Low.

Also, the sum of the current ID1 of the first diode 102 and the current ID2 of the second diode 105 flows through the second capacitor 114 . However, by shifting the triangular wave carrier by 180 degrees, the increase and decrease of the currents of the first diode 102 and the second diode 105 are deviated. Therefore, the instantaneous amount of current flowing into the second capacitor 114 can be reduced. Although this effect cannot be obtained if the triangular wave carriers are the same, it is possible to supply power from the first power supply 120 to the second power supply 119 .

Next, the operation when power is supplied from the second power supply 119 to the first power supply 120 will be described with reference to FIG. FIG. 5 is a diagram showing an example of waveforms of components when the power conversion device 1 is supplying power from the second power supply 119 to the first power supply 120 .

In FIG. 5 , the upper graph shows a waveform 302 of the voltage Vdc2 of the second power supply 119 and a waveform 301 of the voltage Vdc1 of the first power supply 120 . 5 are a triangular carrier waveform 303 generated in control unit 109, a waveform 304 of command value Iref2 for driving second semiconductor switching element 106, and current IL2 of second reactor 108. , a waveform 306 of the current IQ2 flowing through the second semiconductor switching element 106, and a waveform 307 of the current ID2 flowing through the second diode 105, respectively.

A command value Iref2 for driving the second semiconductor switching element 106 is obtained by a voltage detection unit 115 that detects the voltage of the first capacitor 113, a current detection unit 116 that detects the current of the second reactor 108, and the first Values detected by a current detection unit 117 that detects the current of the reactor 107 and a voltage detection unit 118 that detects the voltage of the second capacitor 114 are appropriately processed in the control unit 109 to generate a necessary command value.

For example, when the voltage of the first power supply 120 is desired to follow a certain target voltage, the target voltage is compared with the voltage value of the first capacitor 113 detected by the voltage detection unit 115, and based on the compared value A current command value is generated by proportional-integral control. Then, this current command value Iref1 is compared with the current value of the second reactor 108 detected by the current detection unit 116, and the second semiconductor switching element 106 is controlled by performing proportional integral control based on the compared value. A command value for driving is generated.

A period E in FIG. 5 is a period in which the second drive signal 112 is High. That is, the second drive signal 112 for the second semiconductor switching element 106 is controlled to be ON. During this period E, the current flows through the route of second capacitor 114 -second semiconductor switching element 106 -second reactor 108 -first capacitor 113 . However, part of the current flows through the path of second power supply 119 - second semiconductor switching element 106 - second reactor 108 - second power supply 119 . At this time, the current in second reactor 108 increases at a rate related to the differential voltage between second power supply 119 and first power supply 120 .

Specifically, the amount of increase in the current of the second reactor 108 is obtained by multiplying the difference voltage obtained by subtracting the voltage of the first power supply 120 from the voltage of the second power supply 119 by the period E, and obtaining the inductance of the second reactor 108 ((voltage of second power supply 119−voltage of first power supply 120)×time of period E÷inductance of second reactor 108). Therefore, the larger the difference between the voltage of the second power supply 119 and the voltage of the first power supply 120, the larger the amount of current increase. Also, the longer the period E, the greater the amount of current increase. Furthermore, the smaller the inductance of the second reactor 108, the larger the amount of current increase. Then, more current flows through the second reactor 108 at the end of the period E than at the beginning of the period E.

A period F in FIG. 5 is a period in which the second drive signal 112 is Low. That is, the second semiconductor switching element 106 is controlled to be off. During this period F, current flows through first capacitor 113 -second diode 105 -second reactor 108 -first capacitor 113 . However, part of the current passes through the path of first power supply 120 - second diode 105 - second reactor 108 - first power supply 120 . At this time, the second reactor current IL2 decreases at a rate related to the voltage of the first power supply 120. FIG.

Specifically, the amount of decrease in the current of the second reactor 108 can be obtained by multiplying the voltage of the second power supply 119 by the period F and dividing the result by the value of the inductance of the second reactor 108 (the second voltage of second power supply 119×time of period F/inductance of second reactor 108). Therefore, the higher the voltage of the second power supply 119, the greater the amount of current decrease. Also, the longer the period F, the greater the amount of current decrease. Then, more current flows through the second reactor 108 at the beginning of the period F than at the end of the period F.

Thus, power can be supplied by operating the second chopper circuit when power is supplied in the second direction. Therefore, power supply in the first direction and power supply in the second direction can be performed, and the power conversion device 1 can supply power in both directions.

When the amount of power supply in the first direction and the amount of power supply in the second direction are different, the control unit 109 controls which chopper circuit is operated when power is supplied in the first direction and which is operated when power is supplied in the second direction. It is different from the chopper circuit. That is, a separate chopper circuit is operated in each direction, and a chopper circuit that always operates in both directions can be eliminated. Further, the control unit 109 sets the number of first (third) chopper circuits to be operated when power is supplied in the first direction with a large amount of power supply to the second number of chopper circuits to be operated when power is supplied in the second direction with a small amount of power supply. are operated so as to be greater than the number of chopper circuits of . Specifically, two first (third) chopper circuits are operated and one second chopper circuit is operated.

4 and 5 show the same switching frequency, in the first embodiment, the switching frequency of the first semiconductor switching element 101 of the first (third) chopper circuit for boosting and the step-down frequency It is also assumed that the switching frequencies of the second semiconductor switching elements 106 of the second chopper circuits to be switched are different.

Next, the power supply amount will be explained. In Embodiment 1, two circuits, the first chopper circuit and the third chopper circuit, operate when power is supplied in the first direction, and the second chopper circuit operates when power is supplied in the second direction. are configured to operate in one circuit. This is because the power supply amount in the first direction is greater than the power supply amount in the second direction, as described above.

The reason for such a configuration will be further described using a specific example. For example, assume that the amount of power supplied from the first power supply 120 to the second power supply 119 is 3 kW, and the amount of power supplied from the second power supply 119 to the first power supply 120 is 1 kW. In this case, the amount of power supplied in the first direction is three times the amount of power supplied in the second direction.

Here, if two circuits, the first chopper circuit and the third chopper circuit, are operated as in Embodiment 1, power supply in the first direction is performed by the first chopper circuit and the third chopper circuit, respectively. Power to be supplied can be shared. The sharing here is assumed to be, for example, a case where the first chopper circuit and the third chopper circuit share half of the power to be supplied. In other words, the two circuits will each supply 1.5 kW. Moreover, since the power supply in the second direction operates the second chopper circuit with one circuit, one circuit supplies 1 kW. It should be noted that, in reality, it is not always necessary to divide the work in half, and the ratio of allocating the work may differ.

By doing so, it is possible to configure the converter in a state in which the capacity of the converter is close regardless of which direction power is supplied. Moreover, since each circuit has a separate semiconductor switching element, it is possible to select a semiconductor switching element according to the power.

Assume that the power supply amount in the first direction is 3 kW and the power supply amount in the second direction is 1 kW, all circuits are shared, and both power supplies are operated by the common circuit. In such a case, a reactor or a semiconductor switching element for transmitting 3 kW of power is required as a converter. In other words, even when transmitting 1 kW of power, the reactor and semiconductor switching elements are selected in accordance with the case of transmitting 3 kW of power. That is, when transmitting power of 1 kW, the reactor and the semiconductor switching element are over-specified.

In addition, since the switching speed of the semiconductor switching element is determined according to the conditions for supplying a large amount of power, operating at 1 kW may result in a larger semiconductor switching loss than when the semiconductor is designed exclusively for 1 kW. . Here, the semiconductor switching loss is a loss that occurs when turning on or off a semiconductor switching element. And switching losses in semiconductors decrease as the switching speed increases. The switching speed includes the speed at which the current drops to 0 A, the speed at which the current rises from 0 A to a certain current, the speed at which the voltage drops to 0 V, the speed at which the voltage rises to a certain voltage, and the like.

Generally, however, when turning off or turning on, a surge voltage, which is an overshoot voltage higher than the voltage of the second power supply 119, is applied between the positive electrode and the negative electrode of the semiconductor switching element. This increases as the switching speed increases, and tends to increase as the turn-on and turn-off current increases. Since the surge voltage must be kept within the element rating, the switching speed is adjusted according to the transmission of 3 kW of power with a large current. At 1 kW, the current is small, so the switching speed can be set a little faster, but when operating at 3 kW, the switching speed is adjusted to be slow so that the surge voltage does not exceed the allowable limit. Therefore, the switching loss may increase compared to the case where the switching loss is tuned exclusively for 1 kW.

Therefore, when the amount of power supply in the first direction and the amount of power supply in the second direction are different from each other as in the first embodiment, the operation with a large amount of power supply is performed with a larger number of circuits than the operation with a small amount of power supply. By doing so, it becomes possible to operate with an optimum circuit configuration in each direction.

Also, if a common circuit is used for 3 kW and 1 kW operations, the core loss of the reactor may become larger during 1 kW operation than the reactor core loss of the converter optimized for 1 kW. Iron loss is related to magnetic flux density and core weight, and iron loss increases as magnetic flux density increases and core weight increases. The magnetic flux density is proportional to the current, and the current has a ripple like a triangular wave with respect to the average current, and the magnitude of the current ripple leads to the height of the magnetic flux density. The current ripple is determined by the inductance of the reactor, the voltage applied to the reactor, and the time. For example, in the case of continuous current mode operation of the chopper, the current ripple does not depend on the average value of current flowing. That is, regardless of whether the operation is from the higher voltage to the lower voltage or from the lower voltage to the higher voltage, the inductance of the reactor and the voltage applied to the reactor are the same between the first power supply 120 and the first power supply 120 . As long as the voltages of the two power supplies 119 are constant, they are the same. Also, the current ripple is the same whether the power is 3 kW or 1 kW. Since the magnetic flux density of the core is the same at 3 kW and 1 kW, the core loss is the same at 3 kW and 1 kW.

In Embodiment 1, the first (third) chopper circuit converts the power of 3 kW in two parallel lines in which the first switching leg and the third switching leg are connected in parallel. Power of 1.5 kW can be supplied. Assuming that a common circuit is used for step-up and step-down, the step-down side will supply 1 kW of power in two circuits, so each circuit will supply 0.5 kW of power, and the core loss of the reactor at that time will be 3 kW. This is the same as when power is being transmitted. This means that the core loss of the reactor is doubled even when compared with the case of power transmission of 1 kW in one circuit, and the loss increases.

Therefore, in Embodiment 1, the power supply in the first direction with a large amount of power supply operates with two circuits, the first chopper circuit and the third chopper circuit, and the power in the second direction with a small amount of power supply is operated. The supply is configured such that one second chopper circuit operates, and the second reactor 108 is shared by the second chopper circuit and the third chopper circuit. In other words, one of the chopper circuits for supplying power in the first direction and the chopper circuit for supplying power in the second direction share one second reactor 108 to operate. This makes it possible to reduce the loss and operate with the optimum circuit configuration in each direction.

In this example, the amount of power supplied from the first power supply 120 to the second power supply 119 is 3 kW, and the amount of power supplied from the second power supply 119 to the first power supply 120 is 1 kW. It will be designed for .5 kW. In other words, when power is supplied from the second power supply 119 to the first power supply 120, there is some margin for the designed power capacity. Specifically, the flowing current is 1 kW, which is less than the designed power capacity of 1.5 kW. Since the current flowing is smaller than the power capacity, the conduction loss of the semiconductor switching element is reduced as a result, and the switching loss during turn-on and turn-off is also reduced, resulting in a margin in design.

On the other hand, the iron loss of the reactor is the same as at 3 kW (1.5 kW per circuit) as described above, and the copper loss is reduced by reducing the current flow. Iron loss can be reduced by lowering the current ripple. In a situation where the voltage applied to the reactor is constant and the inductance is fixed, the current ripple can be reduced by shortening the voltage application period. That is, the voltage application period can be shortened by increasing the switching frequency. Then, the current ripple flowing through the reactor is reduced, and as a result, the magnetic flux density is lowered, so that iron loss can be reduced.

In Embodiment 1, it is assumed that the switching frequency of first semiconductor switching element 101 and the frequency of second semiconductor switching element 106 are made different. Accordingly, by selecting an appropriate switching frequency for each switching element and increasing the switching frequency appropriately, the voltage application period can be shortened. Therefore, it becomes possible to reduce the loss of the reactor. However, increasing the switching frequency increases the loss of the semiconductor switching element. By finding the minimum point of the loss of the reactor and the loss of the switching frequency and operating at that point, it becomes possible to operate under conditions with less loss.

In the above example, when power is sent from the second power supply 119 to the first power supply 120, 1 kW per circuit is sufficient, and when power is sent from the first power supply 120 to the second power supply 119, 1.5 kW per circuit. becomes. That is, it is possible to select components suitable for the rated power in each chopper circuit. In the first embodiment, second semiconductor switching element 106 has a smaller current rating than first semiconductor switching element 101 and third semiconductor switching element 103 . As a result, the cost of the second semiconductor switching element 106 can be reduced as compared with the first semiconductor switching element 101 and the third semiconductor switching element 103 . The same is true for the diode 105 that selects a component with a lower current rating than the first diode 102 and the third diode 104 .

Furthermore, when the time for sending power from the first power supply 120 to the second power supply 119 is shorter than the time for sending power from the second power supply 119 to the first power supply 120, the first power supply 120 and the second power supply 119 is a storage battery, and there is a difference in the power and time until the storage battery is fully charged and the power and time until it is completely discharged, such as the allowable values for the current when charging the storage battery and the current when discharging the storage battery are different. coming out.

For example, it is assumed that the time to send power in the second direction is 1 hour and the time to send power in the first direction is 10 seconds. In this case, it is considered that the temperature rise due to the loss due to the current flow and the loss due to the switching operation of the semiconductor switching element is reduced. Therefore, when considering temperature rise as a reference, it is conceivable to further increase the switching frequency to reduce the core loss of the reactor. Also, when the time to send power in the first direction is longer than the time to send power in the second direction, that is, the time to send power in the second direction is 10 seconds and the time to send power in the first direction is 10 seconds. 1 hour. At this time, as a design that allows 1 kW of power to pass through the second reactor 108 for 1 hour, the power passing through the first reactor 107 is designed to have 2 kW for 10 seconds. Time management allows the use of devices with lower current ratings, even under conditions of high power transmission, without the need to construct a converter with a higher current rating.

Also, for example, when power is sent in the first direction, current flows through both the first reactor 107 and the second reactor 108 . On the other hand, no current flows through the first reactor 107 in the second direction. Therefore, the second reactor 108 has a longer operating time and a longer self-heating time. That is, the temperature tends to be higher than that of the first reactor 107 . Therefore, the winding of the second reactor 108 is made thicker than that of the first reactor 107 to reduce the resistance value and the conduction loss, or the inductance value of the second reactor 108 is made thicker than that of the first reactor 107. By making the current ripple of the second reactor 108 smaller than the current ripple of the first reactor 107 to reduce the iron loss, heat generation of the second reactor 108 having a long operating time can be suppressed. can.

Also in Embodiment 1, it is assumed that different rated currents are selected for the first reactor 107 and the second reactor. Also, it is assumed that the third semiconductor switching element 103 and the third diode 104 are selected to have a rated current different from that of the first semiconductor switching element 101 and the first diode 102 . Thereby, the loss can be further suppressed.

Effects of the configuration of the first embodiment of the present disclosure will be described.

The power converter 1 according to Embodiment 1 of the present disclosure includes a plurality of chopper circuits and a control section 109 that controls the chopper circuits. When the amount of power supply in the first direction and the amount of power supply in the second direction are different, the control unit 109 selects different choppers when supplying power in the first direction and when supplying power in the second direction. It is configured to operate the circuit. This eliminates the need to always operate the same circuit in both directions. Also, the number of chopper circuits, components, etc. can be selected according to each power supply amount. In addition, when the power supply amount in one direction and the power supply amount in the second direction are different, the control unit 109 controls the number of chopper circuits to be operated when power is supplied in the first direction and the power in the second direction. It is configured so that the number of chopper circuits to be operated at the time of supply is made different. As a result, when the amounts of power supply are different between the two directions, the number of chopper circuits, components, and the like can be selected according to each amount of power supply. Also, power conversion can be shared by a plurality of circuits. Therefore, loss during bidirectional power supply can be reduced.

Further, the number of chopper circuits operating when power is supplied in the first direction reduces the power in the second direction, especially when the amount of power supplied in the first direction is greater than the amount of power supplied in the second direction. It is configured so that the number of chopper circuits operating at the time of supply can be greater than the number. In particular, power conversion on the side to which a large amount of power is supplied can be shared by a plurality of circuits. Therefore, it is possible to configure the transducer with the transducer capacitance being close in either direction. Furthermore, by configuring the power supply in the first direction to operate with a plurality of chopper circuits, it is possible to reduce the current flowing more than the power capacity. That is, it is possible to give a margin to the designed power capacity. Therefore, the conduction loss of the semiconductor switching element is reduced, and the switching loss during turn-on and turn-off is also reduced. Then, each reactor and each semiconductor switching element constituting each chopper circuit can be selected according to the rated power of each circuit. Therefore, it is possible to prevent the reactor and the semiconductor switching element from becoming over-specified, and it is possible to suppress the switching loss.

In addition, one chopper circuit of the first (third) chopper circuits controlled when power is supplied in the first direction is configured to share a reactor with the chopper circuit controlled when power is supplied in the second direction. It is Specifically, the third chopper circuit controlled when power is supplied in the first direction includes a third switching element, a third diode, and a second reactor 108 that constitutes the second chopper circuit. It is composed by As a result, the iron loss of the reactor can be reduced, and the effect of suppressing the loss is exhibited. Therefore, it is possible to operate with separate circuit configurations in the respective directions of stepping up and stepping down, and it is possible to reduce the loss during bidirectional power supply.

Moreover, at least one of the plurality of first (third) chopper circuits is configured not to share the second reactor 108 with the second chopper circuit. As a result, it is possible to reduce the iron loss of the reactor while realizing appropriate bidirectional operation. Therefore, it is possible to operate with an optimum circuit configuration in each of the up-down and up-down directions, and it is possible to reduce loss during bi-directional power supply.

Among the reactors of the plurality of first (third) chopper circuits, the second reactor 108 shared with the second chopper circuit has a rating different from that of the other first reactors 107. ing. This makes it possible to cope with different operating times and suppress heat generation of the long second reactor 108 . Therefore, loss can be suppressed more.

The second semiconductor switching element 106 has a smaller rated current than the first semiconductor switching element 101 , and the second diode 105 has a smaller rated current than the first diode 102 . As a result, the cost of the second semiconductor switching element 106 in particular can be reduced compared to the first semiconductor switching element 101 and the third semiconductor switching element 103 . Also, the cost of the second diode 105 can be similarly reduced compared to the first diode 102 and the third diode 104 .

Also, the switching frequencies of the first semiconductor switching element 101 and the second semiconductor switching element 106 are different. Thereby, the switching frequency can be increased according to each switching element, and the period in which the voltage is applied can be shortened. Therefore, the current ripple flowing through the reactor is reduced, and as a result, the magnetic flux density is lowered, so that iron loss can be reduced. However, they do not necessarily have to be different, and even if the switching frequencies of the first semiconductor switching element 101 and the second semiconductor switching element 106 are the same, it is possible to reduce the loss during bidirectional power supply described above. is effective.

Also, the phase of the triangular wave carrier 203 and the phase of the triangular wave carrier 208 are shifted by 180 degrees. That is, the first semiconductor switching element 101 and the third semiconductor switching element 103 are controlled with phase timings shifted by 180 degrees. Thereby, the momentary current flowing into the first capacitor 113 and the second capacitor 114 can be reduced. Although this effect can be obtained by varying the rating of each reactor, it is better to make the rating of the reactors of all circuits the same in order to obtain the maximum effect. In this case, the effect of using different reactors cannot be obtained. As for the second reactor 108 and the second reactor 108, the parts can be made the same, so that the converter can be constructed at low cost.

Needless to say, the triangular wave carrier 203 and the triangular wave carrier 208 may have the same phase. That is, the first semiconductor switching element 101 and the third semiconductor switching element 103 may be controlled to operate simultaneously. Also, the phase shift may be other than 180 degrees. Even if the same triangular wave carrier is used, power can be supplied between the first power supply 120 and the second power supply 119, and there is an effect that loss can be reduced during step-up and step-down. In addition, there is no need to worry about the effect of shifting the triangular wave carrier, and by using components with different ratings according to each chopper circuit described above, the effect of reducing loss can be obtained. Further, even if the phase shift is other than 180 degrees, the increase/decrease of the current IL1 of the first reactor 107 and the current IL2 of the second reactor 108 can be shifted, and the increase/decrease of the current IL2 cancels each other, so that the first capacitor 113 can reduce the current flowing into the

Also, although the first capacitor 113 and the second capacitor 114 have been described as electrolytic capacitors, they may be film capacitors or ceramic capacitors. Even in this case, the same effects as described above are obtained.

Also, although IGBTs are used as the semiconductor switching elements, there are no particular restrictions as long as they have a self-extinguishing function. That is, it may be a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) or a HEMT (High Electron Mobility Transistor). The material of the semiconductor switching element may be silicon, silicon carbide, or gallium nitride. Even in these cases, the same effects as described above can be obtained.

The second power supply 119 may be a regulated DC power supply, a chargeable and dischargeable DC power supply such as a battery, or a power-consuming load. The same effect as described above can be obtained even if any power supply is adopted.

Moreover, although the case where each direction is made into a 1st direction and a 2nd direction and different electric power supply amounts were demonstrated, it is not always necessary to make them always different, and they may be equivalent. That is, when the amount of power supplied in both directions is the same, it is possible to operate with the same number of chopper circuits in each direction. In addition, when the number of chopper circuits that can operate when power is supplied in the first direction and the number of chopper circuits that can operate when power is supplied in the second direction are configured to be the same, and the amounts of power supplied in both directions are different. can also be configured to vary the number of chopper circuits to be operated according to the amount of power supply as described above. In any case, it is effective if the chopper circuits that operate bidirectionally can be made different in the case where the amount of bidirectional power supply is different.

Next, Modification 1 of Embodiment 1 will be described. FIG. 6 shows a circuit configuration of Modification 1 of Embodiment 1. In FIG. In the above description, the circuit configuration is based on the assumption that the amount of power supplied in the first direction is greater than the amount of power supplied in the second direction. The power supply amount converted to DC voltage power and output to the first power supply 120 is greater than the power supply amount converted to a different DC voltage power from the first power supply 120 and output to the second power supply 119 It is assumed that there are many cases. That is, in Modification 1, the first direction is the direction in which the DC voltage of the second power supply 119 is converted into power of a different DC voltage and output to the first power supply 120 . The second direction is the direction in which the DC voltage of the first power supply 120 is converted into power of a different DC voltage and output to the second power supply 119 .

The modification is that the plurality of diodes 401, 403, 406 and the plurality of semiconductor switching elements 402, 404, 405 form a fourth switching leg, a fifth switching leg, and a sixth switching leg. Other configurations are the same, and description thereof is omitted.

Specifically, the fourth switching leg is configured by serially connecting a fourth semiconductor switching element 402 provided on the upper arm side and a fourth diode 401 provided on the lower arm side. The first reactor 107 has one terminal connected to the intermediate connection point of the first capacitor 113 and the other terminal connected to the intermediate connection point of the fourth switching leg. The configuration of this fourth switching leg and first reactor 107 is called a fourth chopper circuit.

The fifth switching leg is configured by serially connecting a fifth semiconductor switching element 404 provided on the upper arm side and a fifth diode 403 provided on the lower arm side. The second reactor 108 has one terminal connected to the first capacitor 113 and the other terminal connected to the intermediate connection point of the fifth switching leg. The configuration of this fifth switching leg and the second reactor 108 is referred to as a fifth chopper circuit.

The sixth switching leg is configured by serially connecting a sixth diode 406 provided on the upper arm side and a sixth semiconductor switching element 405 provided on the lower arm side. Second reactor 108 has one terminal connected to first capacitor 113 and the other terminal connected to the intermediate connection point of the sixth switching leg. The configuration of this sixth switching leg and second reactor 108 is referred to as a sixth chopper circuit. By sharing the second reactor 108, loss can be reduced as in the configuration of the first embodiment.

Each semiconductor switching element 402, 404, 405 configured in this way is controlled based on each corresponding drive signal 410, 411, 412. FIG. When power conversion is performed from the voltage of the first power supply 120 to the voltage of the second power supply 119, the control unit 109 operates one sixth chopper circuit. Further, when power conversion is performed from the voltage of the second power supply 119 to the voltage of the first power supply 120, the control unit 109 operates the fourth chopper circuit and the fifth chopper circuit.

In other words, the configuration is such that the chopper circuits that operate can be changed according to the amount of bidirectional power supply. Also, the number of chopper circuits to be operated can be varied according to the amount of power supply. Therefore, even in the configuration of the modified example as described above, it is possible to reduce loss during bidirectional power supply as in the first embodiment.

Next, Modification 2 of Embodiment 1 will be described. FIG. 7 shows a circuit configuration of Modification 2 of Embodiment 1. In FIG. In Embodiment 1, the amount of power supplied in the first direction from the first power supply 120 to the second power supply 119 is the amount of power supplied in the second direction from the second power supply 119 to the first power supply 120. I expected more than that. In addition, in the power supply in the first direction, the first (third) chopper circuit is operated by two circuits, and in the power supply in the second direction, the second chopper circuit is operated by one circuit. Modification 2 shown in FIG. 7 is different in that a seventh switching leg and a third reactor 504 are provided, and the first chopper circuit is connected in parallel. Description of other similar configurations is omitted.

Specifically, the seventh switching leg is configured by serially connecting a seventh diode 502 provided on the upper arm side and a seventh semiconductor switching element 501 provided on the lower arm side. Furthermore, a third reactor 504 is provided, one terminal of the third reactor 504 is connected to the intermediate connection point of the first capacitor 113, and the other terminal is connected to the intermediate connection point of the seventh switching leg. . The configuration of the seventh switching leg and the third reactor 504 is referred to as a seventh chopper circuit.

That is, the seventh chopper circuit has the same configuration as the first chopper circuit, and the configuration in which the first chopper circuit, the third chopper circuit, and the seventh chopper circuit are connected is the same as the first chopper circuit. It is the same as the configuration in which three circuits are connected. Three first chopper circuits are operated in parallel for power supply in the first direction, and one second chopper circuit is operated for power supply in the second direction. Hereinafter, when the first chopper circuit, the third chopper circuit, and the seventh chopper circuit are collectively described, the first chopper circuit (or the first (third, seventh) chopper circuit) may be described as

With such a configuration, in addition to the effect of reducing the loss during bidirectional power supply as described in Embodiment 1, even when the amount of power supplied in the first direction is large, it is shared by a plurality of circuits. It is possible to equalize the amount of power shared by each circuit during bidirectional power supply.

Further, FIG. 8 shows the configuration of Modification 3 of Embodiment 1. As shown in FIG. Specifically, it shows a configuration in which a configuration of a second chopper circuit is added to Modification 2. FIG. The added chopper circuit is configured by serially connecting an eighth semiconductor switching element 602 provided on the upper arm side and an eighth diode 601 provided on the lower arm side. The first reactor 107 has one terminal connected to the intermediate connection point of the first capacitor 113 and the other terminal connected to the intermediate connection point of the eighth switching leg. The configuration of this eighth switching leg and first reactor 107 is referred to as an eighth chopper circuit.

That is, the eighth chopper circuit has the same configuration as the second chopper circuit, and the configuration in which the second chopper circuit and the eighth chopper circuit are connected has two second chopper circuits connected. Same as configuration. In the power conversion from the first power supply 120 to the second power supply 119, the first chopper circuit 3 is operated, and in the power conversion from the second power supply 119 to the first power supply 120, the second chopper The configuration is such that two circuits can be operated.

In this circuit configuration, among the plurality of first chopper circuits, the same number of first (third, seventh) chopper circuits as the number of second chopper circuits share a reactor with the second chopper circuit. there is Also, the number of chopper circuits that operate with a larger amount of power supply can be greater than the number of chopper circuits that operate with a smaller amount of power supply.

With this configuration, in addition to the effect of reducing the loss during bidirectional power supply as described in the first embodiment, each chopper circuit can finely share the amount of bidirectional power supply. , can be operated in a circuit that is more suitable for bi-directional power supplies. Further, by finely adjusting the number, it becomes possible to adjust the power supply amount per circuit shared by the chopper circuit in both directions to a closer amount.

Needless to say, the number of chopper circuits is not limited to that shown in the figure, and can be increased or decreased as appropriate. Further, even in the case shown in Modification 1, it is possible to apply the configuration as in Modification 3.

While this application describes various exemplary embodiments and examples, various features, aspects, and functions described in one or more embodiments may not apply to particular embodiments. can be applied to the embodiments singly or in various combinations.
Accordingly, numerous variations not illustrated are envisioned within the scope of the technology disclosed herein. For example, modification, addition or omission of at least one component, extraction of at least one component, and combination with components of other embodiments shall be included.

1 power conversion device 10 chopper circuit unit 20 processor 30 storage device 101 first semiconductor switching element 102 first diode 103 third semiconductor switching element 104 third diode 105 second diode , 106 second semiconductor switching element, 107 first reactor, 108 second reactor, 109 control unit, 113 first capacitor, 114 second capacitor, 119 second power supply, 120 first power supply, 401 fourth diode 402 fourth semiconductor switching element 403 fifth diode 404 fifth semiconductor switching element 405 sixth semiconductor switching element 406 sixth diode 501 seventh semiconductor switching element 502 7th diode, 504 3rd reactor, 601 8th diode, 602 8th semiconductor switching element.

Claims (9)

A power conversion device capable of bidirectional power supply,
a plurality of chopper circuits;
a control unit that controls the chopper circuit;
has
When the amount of power supplied in the first direction and the amount of power supplied in the second direction are different, the control unit determines whether the amount of power supplied in the first direction is different from the amount of power supplied in the second direction. A power conversion device that operates the chopper circuits and differentiates the number of chopper circuits that are operated when power is supplied in the first direction from the number of chopper circuits that are operated when power is supplied in the second direction. When the amount of power supplied in the first direction is greater than the amount of power supplied in the second direction,
2. The power conversion according to claim 1, wherein the control unit makes the number of the chopper circuits operated during the power supply in the first direction greater than the number of the chopper circuits operated during the power supply in the second direction. Device. One of the plurality of chopper circuits operated by the control unit when power is supplied in the first direction includes the chopper circuit operated by the control unit when power is supplied in the second direction and a reactor. The power converter according to claim 1 or claim 2, which is shared. The plurality of chopper circuits are
a first chopper circuit configured by a first semiconductor switching element, a first diode, and a first reactor and operated by the control unit when power is supplied in the first direction;
A second chopper circuit configured by a second semiconductor switching element, a second diode, and a second reactor, and operated by the control unit when power is supplied from the second direction to the first direction. When,
The third semiconductor switching element, the third diode, and the second reactor that constitutes the second chopper circuit, and is operated by the control unit when power is supplied in the second direction. three chopper circuits;
The power converter according to any one of claims 1 to 3, comprising: 5. The power according to claim 4, wherein the control unit operates the first chopper circuit and the third chopper circuit with a phase shift of 180 degrees when power is supplied from the first direction to the second direction. conversion device. 6. The power converter according to claim 4, wherein the rating of the first reactor and the rating of the second reactor are different ratings. 7. The power converter according to any one of claims 4 to 6, wherein the switching frequencies of said first semiconductor switching element and said third semiconductor switching element are different from the switching frequency of said second semiconductor switching element. The rated current of the second semiconductor switching element is smaller than the rated current of the first semiconductor switching element and the rated current of the third semiconductor switching element, and the rated current of the second diode is the rated current of the first diode. and the rated current of the third diode. The power converter according to any one of claims 4 to 8, wherein the rated power of said first chopper circuit and the rated power of said third chopper circuit are different from the rated power of said second chopper circuit.

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