JP2015012640A - Power conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conversion device that allows obtaining further excellent power-factor improvement effect.SOLUTION: A power conversion device 10 of the present invention includes a rectifier circuit 13, an AC-side circuit 14, a DC-side circuit 15, a control section 16, and a DC current detection section 63. The DC current detection section 63 is provided in the DC-side circuit 15 so as to generate an output corresponding to a direct current flowing through the DC-side circuit 15. The control section 16 estimates an alternating current flowing through the AC-side circuit 14 on the basis of an output of the DC current detection section 63. Further, the control section 16 controls on/off operation of a switching element 47 on the basis of the estimated alternating current.

Description

  The present invention relates to a power conversion device.

  As this type of device, a device having a so-called power factor improving function is widely known. For example, an apparatus disclosed in Japanese Patent Application Laid-Open No. 2006-304586 includes a rectifier that rectifies an AC power supply, a capacitor that smoothes the output of the rectifier, and a short-circuit current that flows from the AC power supply or the rectifier through a reactor. And switch means for controlling the operation pulse of the switch means.

  Further, the apparatus disclosed in Japanese Patent Laid-Open No. 2006-304586 is provided with an input current detector that detects an input current flowing from an AC power supply. Then, the control means generates a drive signal for operating the switch means based on the detected input current.

JP 2006-304586 A

  When the current detection means is provided on the AC side as in the conventional apparatus described above, problems such as noise generation due to the provision of the means and a decrease in power factor improvement accuracy due to the noise occur. The present invention has been made in view of the circumstances exemplified above. That is, an object of the present invention is to provide a power conversion device that can obtain a good power factor improvement effect with low noise.

  The power converter of the present invention includes a rectifier circuit, an AC side circuit, a DC side circuit, and a control unit. The rectifier circuit is provided between the AC voltage input / output unit and the DC voltage input / output unit so as to perform conversion between the AC voltage and the DC voltage. The AC side circuit is an electric circuit through which an AC current flows, and is provided between the AC voltage input / output unit and the rectifier circuit. The DC side circuit is an electric circuit through which a DC current flows, and is provided between the DC voltage input / output unit and the rectifier circuit.

  A switching element is provided in the AC side circuit or the DC side circuit. When the switching element is turned on, a short circuit between a pair of power lines in the AC side circuit or the DC side circuit is performed. The control unit is provided to perform a power factor correction operation by controlling an on / off operation of the switching element.

  The present invention is characterized in that the power conversion device is further configured as follows: the control unit includes a direct current detection unit. The direct current detector is provided in the direct current circuit so as to generate an output corresponding to the direct current flowing through the direct current circuit. And the said control part estimates the alternating current which flows through the said alternating current side circuit based on the output of the said direct current detection part, and controls the on-off operation | movement of the said switching element based on the estimated alternating current It is configured.

  In the power conversion device of the present invention having such a configuration, the DC current detector generates an output corresponding to the DC current flowing through the DC side circuit. Moreover, the said control part estimates the alternating current which flows through the said AC side circuit based on the output of the said direct current detection part. And the said control part controls the ON / OFF operation | movement of the said switching element based on the estimated alternating current.

  Thus, in the power converter of the present invention, no current detection means is provided in the AC side circuit. For this reason, generation | occurrence | production of problems, such as the generation | occurrence | production of the noise resulting from providing this means in the said alternating current circuit, and the fall of the power factor improvement accuracy by this, are suppressed favorably. Therefore, according to the present invention, it is possible to obtain a good power factor improvement effect with low noise.

The figure which shows schematic structure of the power converter device which concerns on one Embodiment of this invention. The figure which shows schematic structure of the modification of the power converter device shown by FIG. The figure which shows schematic structure of the other modification of the power converter device shown by FIG. The figure which shows schematic structure of another modification of the power converter device shown by FIG.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings. In addition, since a modification will prevent understanding of description of one consistent embodiment, if it is inserted during the description of the said embodiment, it is described collectively at the end.

<Configuration>
Referring to FIG. 1, a power conversion device 10 according to an embodiment of the present invention is configured to be able to perform power conversion from an AC voltage to a DC voltage. Specifically, the power conversion device 10 includes an AC power supply 11, a DC load 12, a rectifier circuit 13, an AC side circuit 14, a DC side circuit 15, and a control unit 16.

  An AC power supply 11 (which functions only as an AC voltage output unit in the present embodiment) corresponding to the “AC voltage input / output unit” of the present invention is a so-called commercial power supply, and is provided so as to output an AC voltage having a predetermined waveform. It has been. The DC load 12 (which functions as a DC voltage input unit in the present embodiment) corresponding to the “DC voltage input / output unit” of the present invention includes a DC-DC converter, a secondary battery and / or a so-called motor generator, It is provided so that direct-current power can be input and output. That is, the power conversion device 10 of this embodiment is configured to convert AC power output from the AC power supply 11 into DC power and supply the DC power 12.

  The rectifier circuit 13 is provided between the AC power supply 11 and the DC load 12 so as to perform conversion between the AC voltage and the DC voltage. In this embodiment, the rectifier circuit 13 is a known full-wave rectifier circuit, and includes a plurality of rectifier elements connected to each other in a bridge shape.

  The AC side circuit 14 is an electric circuit through which an AC current flows, and is provided between the AC power supply 11 and the rectifier circuit 13. Specifically, in this embodiment, the AC side circuit 14 includes a first AC power line 41, a second AC power line 42, a filter 43, a first reactor 44, a second reactor 45, and an AC. A side short-circuit line 46 and a bidirectional switching element 47 are provided.

  One end of the first AC power line 41 is a power line (power wiring) connected to one input / output terminal TA <b> 1 in the AC power supply 11, and the other end is connected to the rectifier circuit 13. Similarly, the second AC power line 42 is a power line having one end connected to the other input / output terminal TA <b> 2 in the AC power supply 11, and the other end connected to the rectifier circuit 13. A known filter 43 for noise removal is interposed in the first AC power line 41 and the second AC power line 42 at a position closest to the AC power supply 11, and is connected in parallel with the AC power supply 11. .

  A first reactor 44 is interposed between the filter 43 and the rectifier circuit 13 in the first AC power line 41. Similarly, a second reactor 45 is interposed between the filter 43 and the rectifier circuit 13 in the second AC power line 42. That is, the first reactor 44 and the second reactor 45 are provided between the filter 43 and the AC side short-circuit line 46. In the present embodiment, reactors having the same model number (that is, the same characteristics) are used as the first reactor 44 and the second reactor 45.

  The AC side short-circuit line 46 is positioned between the first reactor 44 and the rectifier circuit 13 in the first AC power line 41, and is positioned between the second reactor 45 and the rectifier circuit 13 in the second AC power line 42. , Is a power line provided to short-circuit. In the present embodiment, a bidirectional switching element 47 is interposed in the AC side short circuit line 46. The bidirectional switching element 47 is a pair of semiconductor switching elements (IGBT or the like) connected in antiparallel, and is short-circuited between the first AC power line 41 and the second AC power line 42 when turned on. Is provided to do.

  The DC side circuit 15 is an electric circuit through which a DC current flows, and is provided between the DC load 12 and the rectifier circuit 13. Specifically, in the present embodiment, the DC side circuit 15 includes a first DC power line 51, a second DC power line 52, a DC side short-circuit line 53, and a smoothing capacitor 54.

  The first DC power line 51 is a power line having one end connected to one input / output terminal TD1 of the DC load 12 and the other end connected to the rectifier circuit 13. Similarly, the second DC power line 52 is a power line having one end connected to the other input / output terminal TD <b> 2 in the DC load 12 and the other end connected to the rectifier circuit 13.

  The DC side short circuit line 53 is provided so as to short circuit the first DC power line 51 and the second DC power line 52. A smoothing capacitor 54 is interposed in the DC short circuit line 53. That is, the smoothing capacitor 54 is connected in parallel with the rectifier circuit 13.

  The control unit 16 is provided to perform a power factor correction operation by controlling the on / off operation of the bidirectional switching element 47. Specifically, in the present embodiment, the control unit 16 includes an AC voltage detection unit 61, a DC voltage detection unit 62, a DC current detection unit 63, and a control circuit 64.

  The AC voltage detection unit 61 is provided in the AC side circuit 14 so as to generate an output corresponding to the input / output voltage of the DC load 12. The DC voltage detection unit 62 is provided in the DC side circuit 15 so as to generate an output corresponding to the input / output voltage of the DC load 12 (that is, the voltage across the terminals of the smoothing capacitor 54). The direct current detection unit 63 is more direct load than the smoothing capacitor 54 in the second direct current power line 52 so as to generate an output corresponding to the input / output current of the direct current load 12 (that is, direct current flowing through the direct current side circuit 15). It is interposed at a position on the 12 side.

  The control circuit 64 is provided to generate a gate signal for controlling the on / off operation of the bidirectional switching element 47 based on the outputs of the AC voltage detection unit 61, the DC voltage detection unit 62, and the DC current detection unit 63. It has been. That is, in the present embodiment, the control circuit 64 estimates the alternating current flowing through the alternating current circuit 14 based on the output of the direct current detection unit 63 instead of directly detecting the alternating current, and converts the estimated alternating current to the estimated alternating current. Based on this, the on / off operation of the bidirectional switching element 47 is controlled. Specifically, the control circuit 64 includes an alternating current estimation unit 64a, a current control value generation unit 64b, and a drive signal generation unit 64c.

  The alternating current estimation unit 64a is provided so as to estimate the alternating current flowing through the alternating circuit 14 based on the outputs of the alternating voltage detection unit 61, the direct voltage detection unit 62, and the direct current detection unit 63. (Details of estimation will be described later). The current control value generation unit 64b is a control value for controlling the input / output current in the AC power supply 11 to a predetermined current value based on the outputs of the AC voltage detection unit 61, the DC voltage detection unit 62, and the AC current estimation unit 64a. (Feedback control value in PWM control) is provided. The drive signal generation unit 64c is provided to generate the above-described gate signal based on the output of the current control value generation unit 64b.

  In the present embodiment, the control circuit 64 (drive signal generator 64c) controls the on / off operation of the bidirectional switching element 47 so as to execute the power factor correction operation in a so-called “full switching mode”. Yes. The “full switching mode” is a mode different from the well-known “partial switching mode”.

  Here, the “partial switching mode” refers to an operation mode in which a specific period (passive operation period) for prohibiting the on operation of the bidirectional switching element 47 is provided during a half cycle of the AC voltage. Specifically, in the “partial switching mode”, the bidirectional switching element 47 is turned on only in about half of the half cycle of the AC voltage. On the other hand, the “full switching mode” refers to an operation mode in which no passive operation period as described above is provided. That is, in the “full switching mode”, an ON pulse is always output from the drive signal generation unit 64c by PWM (for example, about 20 to 25 kHz) during a half cycle of the AC voltage.

<Operation>
Hereinafter, the operation, action and effect of the configuration of the present embodiment will be described. Here, the AC voltage output from the AC power supply 11 is hereinafter referred to as “input voltage”. The AC current that flows through the AC circuit 14 by the output of the sinusoidal AC voltage from the AC power supply 11 is hereinafter referred to as “input current”. Further, the voltage between the terminals of the smoothing capacitor 54 is hereinafter referred to as “output voltage”. The direct current flowing through the direct current side circuit 15 is hereinafter referred to as “load current”.

  The drive signal generation unit 64 c in the control circuit 64 generates a continuous PWM signal as a gate signal in one cycle of the input voltage and outputs it to the bidirectional switching element 47. By the ON / OFF operation of the bidirectional switching element 47 based on such a gate signal, the first AC power line 41 and the second AC power line 42 are intermittently short-circuited. Thereby, a power factor improvement operation is performed.

  Here, in the configuration of the present embodiment, as shown in FIG. 1, the first reactor 44 is provided in the first AC power line 41, and the first reactor is provided in the second AC power line 42. A second reactor 45 having the same model number as 44 is provided. Further, a bidirectional switching element 47 is provided in the AC side short circuit line 46.

  In other words, in the AC side circuit 14, the first AC power line 41 side and the second AC power line 42 side are completely symmetrical. For this reason, the power factor correction operation is similarly performed in one half cycle and the other half cycle in the AC input voltage.

  Specifically, in the present embodiment, the input current is estimated as follows.

If the loss is ignored, the relationship between input and output power is expressed by the following equation. In the following expression, Vin is an input voltage, Iin is an input current, Vdc is an output voltage, Io is a load current (output current), Pin is input power, Po is load power (output power), and Pc is a smoothing capacitor 54. , C is the electrostatic capacity of the smoothing capacitor 54, and t is time.
Pin = Po + Pc
Pin = Vin / Iin
Po = Vdc · Io
Pc = Vdc · C · (dVdc / dt)

For this reason, the input current Iin is expressed by the following equation.
Iin = (Vdc / Vin). {Io + C. (DVdc / dt)}

  Therefore, the input current Iin is estimated from the above formula, the output (Vin) of the AC voltage detector 61, the output (Vdc) of the DC voltage detector 62, and the output (Io) of the DC current detector 63. The The gate signal described above is generated using the input current Iin thus estimated.

  The differential value dVdc / dt of the output voltage Vdc is based on, for example, the difference in voltage value between the rising timing and falling timing of a certain pulse in the gate signal and the time interval between both timings. Is obtained. That is, for example, the rising and falling timings of the next pulse are set using the input current Iin estimated based on the differential value dVdc / dt acquired at the rising and falling of the current pulse.

  Here, in the present embodiment, the AC side circuit 14 is not provided with a circuit portion for detecting the input current Iin. For this reason, impedance imbalance does not occur between the first AC power line 41 side and the second AC power line 42 side. Further, the influence of the filter 43 on the acquisition result of the input current Iin is suppressed as much as possible. In this operation example, the input current Iin is about −25 to +25 A, for example, whereas the output current, that is, the load current Io is about 0 to 10 A, for example. For this reason, the resolution of the load current Io is higher than that of the input current Iin. Therefore, in the present embodiment, the input current Iin is acquired (estimated) with good accuracy.

  Thus, in the present embodiment, the occurrence of common noise due to the impedance imbalance between the first AC power line 41 side and the second AC power line 42 side is suppressed satisfactorily. Also, the accuracy of the acquired value of the input current Iin is good. Therefore, according to this embodiment, it is possible to obtain a good power factor improvement effect with low noise.

<Modification>
Hereinafter, some typical modifications will be exemplified. In the following description of the modified examples, the same reference numerals as those in the above embodiment can be used for portions having the same configurations and functions as those described in the above embodiment. And about description of this part, the description in the above-mentioned embodiment shall be used suitably in the range which is not technically consistent. Needless to say, the modifications are not limited to those listed below. In addition, a part of the above-described embodiment and all or a part of the plurality of modified examples can be combined appropriately as long as they are technically consistent.

  The present invention is not limited to the specific apparatus configuration and operation mode described above. For example, the position of the DC current detection unit 63 is not limited to the position on the DC load 12 side of the smoothing capacitor 54 in the second DC power line 52 as shown in FIG. That is, the DC current detection unit 63 can be provided at an arbitrary position in the first DC power line 51 or the second DC power line 52.

  The present invention is not limited to the configuration in which the AC voltage is boosted before full-wave rectification as in the above-described embodiment (this can be referred to as “AC direct boost type”). Specifically, for example, the present invention can be suitably applied to a so-called “bridgeless boost type” power conversion device 10 as shown in FIG. 2.

  Hereinafter, the configuration of the power conversion device 10 of the present modification will be described with reference to FIG.

  In this modification, the rectifier circuit 13 includes a first rectifier element 13a and a second rectifier element 13b. The first rectifying element 13a is interposed in the first short-circuit line 48a. The first short-circuit line 48 a is provided so as to short-circuit the first DC power line 51 and the second DC power line 52, and an intermediate position thereof is connected to the first reactor 44. Similarly, the second rectifying element 13b is interposed in the second short-circuit line 48b. The second short-circuit line 48 b is provided in parallel with the first short-circuit line 48 a so as to short-circuit the first DC power line 51 and the second DC power line 52, and an intermediate position thereof is connected to the second reactor 45. Has been.

  The cathodes of the first rectifying element 13 a and the second rectifying element 13 b are connected to the first DC power line 51. The anode of the first rectifying element 13 a is connected to the first reactor 44. The anode of the second rectifying element 13 b is connected to the second reactor 45.

  A first switching element 49a made of a semiconductor switching element such as an IGBT is interposed on the second DC power line 52 side of the first short-circuit line 48a. That is, the first switching element 49 a as the “switching element” of the present invention is provided between the connecting portion between the first reactor 44 and the first rectifying element 13 a and the second DC power line 52. Similarly, the 2nd switching element 49b which consists of semiconductor switching elements, such as IGBT, is provided between the connection part of the 2nd reactor 45 and the 2nd rectifier 13b, and the 2nd DC power line 52.

  The present invention can also be suitably applied to a so-called “boost chopper type” configuration as shown in FIG. Hereinafter, the configuration of the power conversion device 10 of the present modification will be described with reference to FIG.

  In this modification, the rectifier circuit 13 is configured as a well-known full-wave rectifier circuit as in the above-described embodiment. On the other hand, in this modification, the AC side circuit 14 is not provided with a reactor. On the other hand, in the DC side circuit 15, in addition to the first DC power line 51, the second DC power line 52, the DC side short circuit line 53, and the smoothing capacitor 54 described above, a boost reactor 55 and a backflow prevention diode 56 are provided. In addition, a boosting short-circuit line 57 and a switching element 58 are provided.

  The step-up reactor 55 is interposed in the first DC power line 51 closest to the rectifier circuit 13 (that is, the rectifier circuit 13 side from the backflow prevention diode 56 and the step-up short-circuit line 57). The backflow prevention diode 56 has an anode connected to the boost reactor 55 and a cathode connected to the smoothing capacitor 54. That is, the boost reactor 55, the backflow prevention diode 56, and the smoothing capacitor 54 are connected in series in this order.

  The boosting short-circuit line 57 includes a position between the boosting reactor 55 and the backflow prevention diode 56 in the first DC power line 51, a position between the rectifier circuit 13 and the smoothing capacitor 54 in the second DC power line 52, Are provided so as to short-circuit each other. A switching element 58 made of IGBT or the like is interposed in the boosting short-circuit line 57.

  The present invention is not limited to a configuration capable of performing only one-way power conversion from alternating current to direct current as in the above-described embodiment. That is, the present invention can be favorably applied to, for example, a configuration capable of bidirectional power conversion from direct current to alternating current and direct current to alternating current. FIG. 4 corresponds to such a modification. That is, in FIG. 4, the power conversion device 10 converts the AC power output from the AC power source 11 into DC power and supplies it to the DC load 12, and converts the DC power output from the DC load 12 into AC power. It is configured to convert and supply to the AC power supply 11 side.

  Specifically, in this modification, the rectifier circuit 13 is configured by a plurality of rectifying switching elements 131 to 134 that are bridge-connected (more specifically, full-bridge connection). Control terminals (gate terminals) in these rectifying switching elements 131 to 134 are connected to other signal generation units (not shown) in the control circuit 64.

  The rectifying switching element 131 and the rectifying switching element 132 are connected in series between the first DC power line 51 and the second DC power line 52 in this order. A connecting portion between the rectifying switching element 131 and the rectifying switching element 132 is connected to the first AC power line 41. Similarly, the rectifying switching element 133 and the rectifying switching element 134 are connected in series between the first DC power line 51 and the second DC power line 52 in this order. The series connection body of the rectification switching element 133 and the rectification switching element 134 is between the series connection body of the rectification switching element 131 and the rectification switching element 132 and the DC side short-circuit line 53 (smoothing capacitor 54). Is provided. A connecting portion between the rectifying switching element 133 and the rectifying switching element 134 is connected to the second AC power line 42.

  In such a modification, the power conversion device 10 can convert a DC voltage into an AC voltage. In this case, the AC power supply 11 is a commercial power supply (system power supply), the DC load 12 is an in-vehicle battery, and the main part of the circuit configuration in the power conversion device 10 is provided on the electric vehicle side. In such a configuration, there is a case where so-called “V2H (Vehicle to Home)” or “V2G (Vehicle to Grid)” is performed in which DC power is output from the DC load 12 and AC power is supplied to the AC power supply 11 side. .

  Also in this case, the alternating current flowing through the alternating current circuit 14 is estimated by the alternating current estimation unit 64a based on the outputs of the alternating voltage detection unit 61, the direct current voltage detection unit 62, and the direct current detection unit 63. . Based on the estimated value of the alternating current and the outputs of the alternating voltage detection unit 61 and the direct voltage detection unit 62, control of the rectifying switching elements 131 to 134, that is, inverter control is performed. At this time, in such an operation example, the control of V2H or V2G can be performed with high accuracy by using the output AC current estimated with good accuracy.

  Also in the configurations of these modified examples, the influence of the filter 43 on the acquisition result of the input current Iin is suppressed as much as possible as in the above-described embodiment. Therefore, according to the configuration of the present modification, an even better power factor improvement effect can be obtained. In particular, as described above, AC current is acquired not by direct detection by a sensor but by estimation based on a DC current detection value, and by using the “full switching mode”, more accurate power factor improvement control can be performed.

  When a current detection sensor for detecting a direct current is provided in advance in the direct current load 12 side or the direct current side circuit 15, such a current detection sensor can be used as the direct current detection unit 63. Specifically, for example, a secondary current detection sensor of a DC-DC converter provided on the DC load 12 side can also be used as the DC current detection unit 63.

  Other modifications not specifically mentioned are naturally included in the technical scope of the present invention without departing from the essential part of the present invention. In addition, in each element constituting the means for solving the problems of the present invention, elements expressed in terms of function and function are specific configurations disclosed in the above-described embodiments and modifications, and equivalents thereof. In addition to objects, any configuration capable of realizing the action / function is included.

  DESCRIPTION OF SYMBOLS 10 ... Power converter, 11 ... AC power supply, 12 ... DC load, 13 ... Rectifier circuit, 14 ... AC side circuit, 15 ... DC side circuit, 16 ... Control part, 41 ... First AC power line, 42 ... Second AC power line, 43 ... filter, 44 ... first reactor, 45 ... second reactor, 46 ... AC side short circuit line, 47 ... bidirectional switching element, 51 ... first DC power line, 52 ... second DC power line, 53 ... DC side short circuit line, 54 ... smoothing capacitor, 61 ... AC voltage detector, 62 ... DC voltage detector, 63 ... DC current detector, 64 ... control circuit, 64a ... AC current estimator, 64b ... current control value Generation unit, 64c... Drive signal generation unit.

Claims (5)

A rectifier circuit (13) provided between the AC voltage input / output unit (11) and the DC voltage input / output unit (12) so as to perform conversion between the AC voltage and the DC voltage;
An electric circuit through which an alternating current flows, an alternating circuit (14) provided between the alternating voltage input / output unit and the rectifier circuit;
An electric circuit through which a direct current flows, a direct current side circuit (15) provided between the direct current voltage input / output unit and the rectifier circuit;
By controlling the on / off operation of the switching element (47; 49a, 49b; 58) provided in the AC side circuit or the DC side circuit so as to short-circuit between the pair of power lines when turned on, A control unit (16) provided to perform rate improvement operation;
A power conversion device (10) comprising:
The controller is
A direct current detector (63) provided in the direct current circuit so as to generate an output corresponding to the direct current flowing through the direct current circuit;
The alternating current flowing through the alternating current side circuit is estimated based on the output of the direct current detection unit, and the on / off operation of the switching element is controlled based on the estimated alternating current. A power converter. The AC side circuit is:
A first AC power line (41), which is a power line connected to one input / output terminal (TA1) in the AC voltage input / output unit;
A second AC power line (42), which is a power line connected to the other input / output terminal (TA2) in the AC voltage input / output unit;
A first reactor (44), which is a reactor provided in the first AC power line;
A second reactor (45) which is a reactor provided in the second AC power line;
An AC side short-circuit line (which is a power line provided to short-circuit a power line between the first reactor and the rectifier circuit and a power line between the second reactor and the rectifier circuit ( 46) and
With
The rectifier circuit is a full-wave rectifier circuit connected in parallel with a smoothing capacitor (54) provided in the DC side circuit,
The power conversion device according to claim 1, wherein the switching element is a bidirectional switching element (47) provided in the short-circuit line. The AC side circuit is:
A first AC power line (41), which is a power line connected to one input / output terminal (TA1) in the AC voltage input / output unit;
A second AC power line (42), which is a power line connected to the other input / output terminal (TA2) in the AC voltage input / output unit;
A first reactor (44), which is a reactor provided in the first AC power line;
A second reactor (45) which is a reactor provided in the second AC power line;
With
The DC side circuit is:
A first DC power line (51), which is a power line connected to one input / output terminal (TD1) in the DC voltage input / output unit;
A second DC power line (52), which is a power line connected to the other input / output terminal (TD2) in the DC voltage input / output unit;
A DC side short-circuit line (53), which is a power line provided to short-circuit the first DC power line and the second DC power line;
A smoothing capacitor (54) provided in the short-circuit line;
With
The rectifier circuit is
A first rectifying element (13a), which is a rectifying element provided in a power line connecting the first reactor and the first DC power line;
A second rectifying element (13b), which is a rectifying element provided in a power line connecting the second reactor and the first DC power line;
With
The first switching element (49a) as the switching element is provided between a connection portion between the first reactor and the first rectifying element and the second DC power line,
The second switching element (49b) as the switching element is provided between a connection portion between the second reactor and the second rectifying element and the second DC power line. The power converter according to 1. The AC side circuit is:
A first AC power line (41), which is a power line connected to one input / output terminal (TA1) in the AC voltage input / output unit;
A second AC power line (42), which is a power line connected to the other input / output terminal (TA2) in the AC voltage input / output unit;
A first reactor (44), which is a reactor provided in the first AC power line;
A second reactor (45) which is a reactor provided in the second AC power line;
An AC side short-circuit line (which is a power line provided to short-circuit a power line between the first reactor and the rectifier circuit and a power line between the second reactor and the rectifier circuit ( 46) and
With
The rectifier circuit is composed of a plurality of semiconductor switching elements bridge-connected to each other, and is an inverter circuit connected in parallel with a smoothing capacitor (54) provided in the DC side circuit,
The power conversion device according to claim 1, wherein the switching element is a bidirectional switching element (47) provided in the short-circuit line.   The power conversion device according to claim 1, wherein the switching element is driven in a full switching mode different from the partial switching mode.

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