JP2010093868A - Bidirectional power converter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bidirectional power converter which can be used for a voltage type or a current type thereby improving convenience. <P>SOLUTION: The bidirectional power converter 10a for converting power between AC and DC by a matrix converter A includes: a DC side inductor L<SB>D</SB>provided on both or either of a positive terminal and a negative terminal of a DC power source Ga; AC side inductors L<SB>U</SB>, L<SB>V</SB>, L<SB>W</SB>provided on phases U, V, W of an AC line respectively; a DC side switch SW<SB>D</SB>provided in parallel to the DC inductor L<SB>D</SB>; and AC side switches SWU, SW<SB>V</SB>, SW<SB>W</SB>provided in parallel to the AC side inductors L<SB>U</SB>, L<SB>V</SB>, L<SB>W</SB>respectively. When the power converter is used as a current type, the DC side switch SW<SB>D</SB>is turned off, the AC side switches SW<SB>U</SB>, SW<SB>V</SB>, SW<SB>W</SB>are all turned on. When it is used as a voltage type, the DC side switch SW<SB>D</SB>is turned on and the AC side switches SW<SB>U</SB>, SW<SB>V</SB>, SW<SB>W</SB>are all turned off. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bidirectional power converter that performs power conversion between AC and DC.

  As a power converter for converting power from direct current to alternating current or from alternating current to direct current, a voltage type and a current type are known. When constructing a system using such a power converter, the choice between the voltage-type power converter and the current-type power converter usually depends on the magnitude of the voltage on the DC side and the voltage on the AC side. Determined by relationship. That is, when the AC side voltage is larger than the DC side voltage, the power converter is of a current type, and when the AC side voltage is smaller than the DC side voltage, the power converter is It shall be of voltage type.

  By the way, conventionally, there is one provided with a matrix converter as a bidirectional power converter that performs power conversion between AC and DC.

For example, Patent Document 1 below includes a matrix converter in which the upper and lower arms of each phase are bidirectional switches composed of a pair of switches whose conduction directions are opposite to each other. Bidirectional power converters that convert power to and from each other are disclosed.
JP 2005-348544 A

  However, although the conventional bidirectional power converter has the advantage of performing power conversion between AC and DC, the voltage type has a configuration of only the voltage type, and the current type has only the current type. The actual situation is that the voltage type and the current type are not properly used in one bidirectional power converter. For example, the bidirectional power converter described in Patent Document 1 has only a voltage type configuration.

  Therefore, for example, when the voltage on the AC side is larger (or smaller) than the voltage on the DC side, when using a voltage-type (or current-type) bidirectional power converter, the voltage on the DC side is It is necessary to step up (or step down) the voltage and input it to the voltage type (or current type) bidirectional power converter, which is not convenient.

  Therefore, an object of the present invention is to provide a bidirectional power converter that can be selectively used as a voltage type and a current type, thereby improving convenience.

  In order to solve the above-mentioned problems, the present invention provides a bidirectional power converter according to the following first to fourth aspects.

(1) Bidirectional power converter according to the first aspect As the upper and lower arms of each phase, a matrix converter using a bidirectional switch composed of a pair of switches whose conduction directions are opposite to each other is used to exchange between AC and DC. In a bidirectional power converter that performs power conversion, a DC side inductor is provided on both or one of the positive terminal side and negative terminal side of the DC power source connected to the DC side, and each phase or single phase of the AC line is provided. Is provided with an AC side inductor in each phase or any one phase, a DC side switch is provided in parallel with the DC side inductor, an AC side switch is provided in parallel with the AC side inductor, and when used as a current source, Turn off the DC side switch in parallel with the DC side inductor, and turn off all the AC side switches in parallel with the AC side inductor. When used as a voltage type, the bidirectional switch is characterized by turning on the direct current side switch in parallel with the direct current side inductor and turning off all the alternating current side switches in parallel with the alternating current side inductor. Power converter.

  In the bidirectional power converter according to the first aspect of the present invention, when the DC side switch parallel to the DC side inductor is turned off and all the AC side switches parallel to the AC side inductor are turned on, It is possible to realize a circuit configuration to be configured as a current type, that is, a circuit configuration of “DC power supply” → “DC inductor” → “matrix converter” → “AC load” from the DC side to the AC side.

  Further, when the DC side switch in parallel with the DC side inductor is turned on and all the AC side switches in parallel with the AC side inductor are turned off, the circuit configuration to be configured as a voltage form, that is, from the DC side It is possible to realize a circuit configuration of “DC power supply” → “matrix converter” → “AC inductor” → “AC load” to the AC side.

  As described above, according to the bidirectional power converter of the first aspect of the present invention, it is possible to use one bidirectional power converter in either a current type or a voltage type, thereby improving convenience. Can be achieved.

  The bidirectional power converter according to the first aspect of the present invention can be suitably used, for example, as a grid interconnection inverter.

(2) Bidirectional power converter according to the second mode As the upper and lower arms of each phase, the matrix converter using a bidirectional switch composed of a pair of switches whose conduction directions are opposite to each other is used to exchange between AC and DC. In a bidirectional power converter that performs power conversion, an inductor is provided on both or one of the positive terminal side and the negative terminal side of the DC power source connected to the DC side, and a capacitor is provided between each phase of the AC line, or When a capacitor Y-connected to each phase of the AC line is provided, a DC side switch is provided in parallel with the inductor, and an AC side switch is provided in series with the capacitor. Turn off the DC side switch and turn on all the AC side switches in series with the capacitor. When used as a pressure type, the bidirectional power converter is characterized in that the DC side switch in parallel with the inductor is turned on and all the AC side switches in series with the capacitor are turned off.

  In the bidirectional power converter according to the second aspect of the present invention, when the DC side switch in parallel with the inductor is turned off and all the AC side switches in series with the capacitor are turned on, the current type is configured. It is possible to realize a circuit configuration to be realized, that is, a circuit configuration of “DC power supply” → “inductor” → “matrix converter” → “capacitor” → “AC side load” from the DC side to the AC side.

  Further, when the DC side switch in parallel with the inductor is turned on and all the AC side switches in series with the capacitor are turned off, a circuit configuration to be configured as a voltage type, that is, from the DC side to the AC side. A circuit configuration of “DC power supply” → “matrix converter” → “AC side load” can be realized.

  As described above, according to the bidirectional power converter of the second aspect of the present invention, it is possible to use one bidirectional power converter of either current type or voltage type, thereby improving convenience. Can be achieved.

  The bidirectional power converter according to the second aspect of the present invention is, for example, as a motor driving inverter when converting power from DC to AC, and when converting power from AC to DC, for example, power generation It can be suitably used as a machine rectifier converter.

(3) Bidirectional power converter according to the third aspect The AC and DC are mutually exchanged by a matrix converter that uses a bidirectional switch composed of a pair of switches whose conduction directions are opposite to each other as the upper and lower arms of each phase. In a bidirectional power converter that performs power conversion, a DC side inductor is provided on both or one of the positive terminal side and the negative terminal side of a DC power source connected to the DC side, and the DC side inductor and the matrix converter A series circuit composed of a capacitor and a DC side switch is provided in parallel with the DC power supply. In the case of each phase or single phase of the AC line, an AC side inductor is provided for each phase or any one phase, and the AC side inductor If the AC side switch is provided in parallel with each other and used as a current source, the DC side switch in series with the capacitor And when all the AC side switches in parallel with the AC side inductor are turned on and used as a voltage type, the DC side switch in series with the capacitor is turned on and in parallel with the AC side inductor. A bidirectional power converter characterized in that all the AC side switches are turned off.

  In the bidirectional power converter according to the third aspect of the present invention, when the DC switch in series with the capacitor is turned off and all the AC switches in parallel with the AC inductor are turned on, In other words, a circuit configuration of “DC power supply” → “DC inductor” → “matrix converter” → “AC load” from the DC side to the AC side can be realized.

  In addition, when the DC side switch in series with the capacitor is turned on and all the AC side switches in parallel with the AC side inductor are turned off, a circuit configuration to be configured as a voltage type, that is, from the DC side to the AC side It is possible to realize a circuit configuration of “DC power supply” → “DC inductor” → “capacitor” → “matrix converter” → “AC inductor” → “AC load”.

  As described above, according to the bidirectional power converter of the third aspect of the present invention, one bidirectional power converter can be used in either a current type or a voltage type, thereby improving convenience. Can be achieved.

  The bidirectional power converter according to the third aspect of the present invention can be suitably used as a grid interconnection inverter, for example.

(4) Bidirectional power converter according to the fourth aspect As the upper and lower arms of each phase, the matrix converter using a bidirectional switch composed of a pair of switches whose conduction directions are opposite to each other is used to exchange between AC and DC. In a bidirectional power converter that performs power conversion, an inductor is provided on both or one of the positive terminal side and the negative terminal side of a direct current power source connected to the direct current side, and a direct current is provided between the inductor and the matrix converter. A series circuit consisting of a side capacitor and a DC side switch is provided in parallel with the DC power supply, and a series circuit consisting of an AC side capacitor and an AC side switch is provided between each phase of the AC line, or Y connection is made to each phase of the AC line In the case where a series circuit composed of an AC capacitor and an AC switch is provided and used as a current source, the DC side When the DC side switch in series with the capacitor is turned off and all the AC side switches in series with the AC side capacitor are turned on and used as a voltage type, the DC side switch in series with the DC side capacitor is turned on. And all the said AC side switches in series with the said AC side capacitor are turned off, The bidirectional | two-way power converter characterized by the above-mentioned.

  In the bidirectional power converter according to the fourth aspect of the present invention, when the DC side switch in series with the DC side capacitor is turned off and all the AC side switches in series with the AC side capacitor are turned on, It is possible to realize a circuit configuration that should be configured as a current type, that is, from the DC side to the AC side: “DC power supply” → “inductor” → “matrix converter” → “AC capacitor” → “AC load” It becomes.

  Further, when the DC side switch in series with the DC side capacitor is turned on and all the AC side switches in series with the AC side capacitor are turned off, the circuit configuration to be configured as a voltage form, that is, from the DC side It becomes possible to realize a circuit configuration of “DC power supply” → “inductor” → “DC capacitor” → “matrix converter” → “AC load” to the AC side.

  As described above, according to the bidirectional power converter of the fourth aspect of the present invention, it is possible to use one bidirectional power converter of either a current type or a voltage type, thereby improving convenience. Can be achieved.

  The bidirectional power converter according to the fourth aspect of the present invention is, for example, as a motor driving inverter when converting power from DC to AC, and when converting power from AC to DC, for example, power generation It can be suitably used as a machine rectifier converter.

  In the bidirectional power converter according to the first to fourth aspects of the present invention, when used as a current source, when power is supplied from the DC side to the AC side, the upper arm of each phase of the matrix converter is Among the constituent switches, the switch that conducts from the direct current side to the alternating current side is switched, while the switch that conducts from the alternating current side to the direct current side is always off, and the switch constituting the lower arm of each phase of the matrix converter Among these, a mode in which a switch conducting from the DC side to the AC side is always turned off, while a switch conducting from the AC side to the DC side is switched can be exemplified. With such switching control, it is possible to satisfactorily supply power from the DC side to the AC side when used as a current source.

  In the bidirectional power converter according to the first to fourth aspects of the present invention, when used as a current source, when power is supplied from the AC side to the DC side, the upper arm of each phase of the matrix converter is Among the constituent switches, the switch that conducts from the AC side to the DC side is switched, while the switch that conducts from the DC side to the AC side is always off, and the switch constituting the lower arm of each phase of the matrix converter Among them, a mode in which a switch conducting from the AC side to the DC side is always turned off, while a switch conducting from the DC side to the AC side is switched can be exemplified. With such switching control, power supply from the AC side to the DC side can be satisfactorily performed when used as a current source.

  In the bidirectional power converter according to the first to fourth aspects of the present invention, when used as a voltage type, the direction of the current flowing through each phase of the AC line is in the direction from the DC side to the AC side. Of the switches constituting the upper arm of the matrix converter, the switch that conducts from the DC side to the AC side is switched, while the switch that conducts from the AC side to the DC side is always off, and the matrix Of the switches constituting the lower arm of the converter, the switch that conducts from the DC side to the AC side is always on, while the switch that conducts from the AC side to the DC side is always off, and the switch from the AC side to the DC side is always on. When it is in the direction of heading, it conducts from the AC side to the DC side among the switches that constitute the lower arm of the phase of the matrix converter. While switching the switch, the switch that conducts from the DC side to the AC side is always turned off, and among the switches that constitute the upper arm of the phase of the matrix converter, the switch that conducts from the AC side to the DC side is always turned on On the other hand, the mode which always turns off the switch which conducts from the direct current side to the alternating current side can be illustrated. By such switching control, bidirectional power conversion can be performed satisfactorily when used as a voltage type.

  As described above, according to the present invention, it is possible to provide a bidirectional power converter that can be selectively used as a voltage type and a current type, thereby improving convenience.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, the following embodiment is an example which actualized this invention, Comprising: The thing of the character which limits the technical scope of this invention is not.

(First embodiment)
First, a case where the bidirectional power converter according to the first embodiment of the present invention is used as a grid interconnection inverter will be described as an example.

  FIG. 1 is a circuit diagram showing a schematic configuration of a bidirectional power converter 10a according to the first embodiment. The bidirectional power converter 10a shown in FIG. 1 controls the matrix converter A, the DC side circuit 11a of the matrix converter A, the AC side circuit 12a of the matrix converter A, and the entire bidirectional power converter 10a. And a control unit 13a.

  The matrix converter A is a three-phase converter in the present embodiment, and three pairs of arms B1, B2, and B3 are connected in parallel.

  In the arm pair B1, B2, B3, upper arms C1, C2, C3 and lower arms C6, C5, C4 are connected in series, respectively.

  The upper arms C1, C2, C3 and the lower arms C6, C5, C4 are all formed of bidirectional switches. The bidirectional switches C1, C2, C3, C4, C5, and C6 are respectively a pair of switches (S1a, S1b), (S2a, S2b), (S3a, S3b) that are connected in parallel with the conduction directions being opposite to each other. , (S4a, S4b), (S5a, S5b), (S6a, S6b). Here, each of the switches S1a to S6a and S1b to S6b is a reverse blocking IGBT (Insulated Gate Bipolar Transistor).

  Of the upper and lower arms referred to in this specification, the upper arm refers to an arm group (C1, C2, and C3 in FIG. 1) connected to the positive terminal side of the DC power supply, and the lower arm refers to the minus of the DC power supply. The arm group (C6, C5, C4 in FIG. 1) connected to the terminal side is indicated.

  The upper arm C1, C2, C3 and the lower arm C6, C5, C4 of the matrix converter A are switched (switching control) between an energized state (on state) and a non-energized state (off state) by the control unit 13a. And is connected to the output system of the control unit 13a.

  The DC side circuit 11a of the matrix converter A has a DC power supply Ga connected to the input side and a matrix converter A connected to the output side. The DC power source Ga may be any one as long as a desired DC output can be obtained. Examples of the direct current power source Ga include, but are not limited to, a solar cell, a fuel cell, and a combination of an engine, a generator, and a rectifier.

The DC side circuit 11a includes a DC side inductor L _D connected in series to the connection line on at least one of the plus terminal side and the minus terminal side (here, the plus terminal side) of the DC power supply Ga. Is provided.

The connection line provided with the DC side inductor L _D is provided with a DC side switch SW _D connected in parallel with the DC side inductor L _D. The DC-side switch SW _D is here, there is a relay switch. DC-side switch SW _D is, the control unit 13a, being adapted to switch (ON / OFF) control is performed, and is connected to the output system of the control unit 13a.

The AC side circuit 12a of the matrix converter A includes an arm pair B1, B2, B3 of each arm pair B1, B2, B3 between the upper arm C1, C2, C3 and the lower arm C6, C5, C4, respectively. , U-phase, V-phase, and W-phase three-phase lines U, V, and W are connected to an AC load (here, a three-phase system) Ea. The U-phase, V-phase, and W-phase lines U, V, and _W are provided with AC-side inductors L _U , L _V , and L _W connected in series to the lines U, V, and W, respectively. ing.

Each line U, V, _W is provided with AC side switches SW _U , SW _V , SW _W respectively connected in parallel with AC side inductors L _U , L _V , L _W. The AC switches SW _U , SW _V , and SW _W are relay switches here. The AC side switches SW _U , SW _V , and SW _W are subjected to switching (on / off) control by the control unit 13a and are connected to the output system of the control unit 13a.

Although not shown, inductors L _U , L _V , L connected in parallel to AC switches SW _U , SW _V , SW _W in U-phase, V-phase, and W-phase lines U, V, W are shown. _{Between W} and the load Ea, a capacitor connected in parallel to each of the lines U, V, and W, and a series connection on the load side of the lines U, V, and W from the capacitor, respectively. One or a plurality of filters including inductors may be provided. The same applies to the AC side circuit 12a of the third embodiment shown in FIG.

In bidirectional power converter 10a having such a configuration, each arm and the DC-side switch SW _D and AC-side switch SW _U matrix converter A by the control unit 13a, by SW _V, the control of the SW _W is carried out, The power converter 10a can perform power conversion between AC and DC in a state where the voltage converter or the current converter is appropriately selected.

  Specifically, the control unit 13 a includes a CPU (Central Processing Unit) 14 and a storage unit 15. The storage unit 15 includes a ROM (Read Only Memory) 151 and a RAM (Random Access Memory) 152, and stores various control programs and necessary functions and tables.

Control unit 13a, the CPU 14, reads out the switching control program from the storage unit 15 and executing the readout switching control program, each arm and the DC-side switch SW _D and AC-side switch SW _U of the matrix converter A, SW It is configured to perform switching control of _V and SW _W. This configuration is the same for the control units 13b to 13d of the second to fourth embodiments described later.

FIG. 2 is a diagram showing the switching control state of each arm of the matrix converter A and the DC side switch SW _D and the AC side switches SW _U , SW _V , SW _W in the bidirectional power converter 10a of the first embodiment. 2A shows the switching control state when used as a current type, and FIG. 2B shows the switching control state when used as a voltage type. In FIG. 2, the controller 13a is not shown. The same applies to FIGS. 4, 6 and 8 described later.

In the bidirectional power converter 10a of the first embodiment, the control unit 13a receives an instruction signal input from an input system (for example, from a switching unit such as a switch (not shown) that selectively switches between a current type and a voltage type). When the current type is used based on the instruction signal) (for example, when the AC side voltage is larger than the DC side voltage), the DC side switch SW _D parallel to the DC side inductor L _D is turned off, In addition, all the AC side switches SW _U , SW _V , SW _W in parallel with the AC side inductors L _U , L _V , L _W are turned on (see FIG. 2A).

On the other hand, when used as a voltage type (for example, when the voltage on the AC side is smaller than the voltage on the DC side), the DC side switch SW _D parallel to the DC side inductor L _D is turned on, and the AC side All the AC side switches SW _U , SW _V , SW _W in parallel with the inductors L _U , L _V , L _W are turned off (see FIG. 2B).

  It should be noted that the current type or the voltage type may be switched by direct human operation to the switching means without using the control unit 10a. Further, the control unit 10a may automatically perform switching between the current type and the voltage type of the switching unit based on detection signals from voltage sensors provided on the DC side and the AC side, respectively, regardless of human operation. . The same applies to the bidirectional power converters 10b to 10d of the second to fourth embodiments described later.

In bidirectional power converter 10a of the first embodiment described above, as shown in FIG. 2 (a), the current to the DC-side inductor L _D in parallel with the DC-side switch SW _D OFF (DC side inductor L _D a state) that passes through, and the AC side inductor L _U, L _V, L _W parallel with the AC side switch SW _U, SW _V, SW _W all on (AC side inductor L _U, L _V, current L _W Circuit state to be configured as a current type, that is, from the DC side to the AC side, “DC power supply Ga” → “DC inductor L _D ” → “matrix converter A” → “AC side system” The circuit configuration of “Ea” can be realized.

Further, as shown in FIG. 2B, the DC side switch SW _D in parallel with the DC side inductor L _D is turned on (the current does not pass through the DC side inductor L _D ), and the AC side inductors L _U , The AC side switches SW _U , SW _V , and SW _W in parallel with L _V and L _W are all turned off (current is passed through the AC side inductors L _U , L _V , and L _W ) to form a voltage type A circuit configuration to be realized, that is, a circuit configuration of “DC power supply Ga” → “matrix converter A” → “AC side inductors L _U , L _V , L _W ” → “AC side system Ea” from the DC side to the AC side is realized. It becomes possible.

  As described above, according to the bidirectional power converter 10a of the first embodiment, it is possible to selectively use the current type and the voltage type with one bidirectional power converter 10a. Can be easily used without being conscious of the magnitude relationship between the voltage on the AC side and the voltage on the AC side (for example, without providing a circuit for stepping up or down the voltage on the DC side).

(Second Embodiment)
Next, regarding the bidirectional power converter according to the second embodiment of the present invention, when converting power from direct current to alternating current, as a motor drive inverter, and when converting power from alternating current to direct current, A case of using as a machine rectifier converter will be described as an example.

  FIG. 3 is a circuit diagram showing a schematic configuration of the bidirectional power converter 10b according to the second embodiment. The bidirectional power converter 10b shown in FIG. 3 controls the matrix converter A, the DC side circuit 11a of the matrix converter A, the AC side circuit 12b of the matrix converter A, and the entire bidirectional power converter 10b. And a control unit 13b.

  Hereinafter, the bidirectional power converter 10b of the second embodiment will be described focusing on differences from the bidirectional power converter 10a of the first embodiment. In FIG. 3, the same components as those of the bidirectional power converter 10a of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The DC side circuit 11a of the matrix converter A has a DC power supply Gb connected to the input side and a matrix converter A connected to the output side. Here, the DC power supply Gb is a rechargeable secondary battery (storage battery), a capacitor, or the like.

The AC side circuit 12b of the matrix converter A is connected to the AC side between the upper and lower arms of each arm pair B1, B2, B3 via U-phase, V-phase, and W-phase three-phase lines U, V, and W, respectively. A load (here, a three-phase AC motor acting as a drive source and a generator) Eb is connected. The U-phase, V-phase, and W-phase lines U, V, and W are respectively replaced with the AC-side inductors L _U , L _V , and L _W and the switches SW _U , SW _V , and SW _{W according} to the first embodiment. The AC capacitors S _U , C _V , C _W and AC switches SW _U , SW _V , SW _W are connected in parallel to the lines U, V, W (Y-connected). A circuit is provided.

Although not shown, capacitors C _U , C _V , C connected in series to AC side switches SW _U , SW _V , SW _W in U-phase, V-phase, W-phase lines U, V, W. _{Between W} and a load Eb, an inductor connected in series with each of the lines U, V, and W and a parallel connection on the load side with respect to each of the lines U, V, and W from the inductor It is also possible to provide one or a plurality of filters composed of capacitors. The same applies to the AC side circuit 12b of the fourth embodiment shown in FIG.

In bidirectional power converter 10b having such a configuration, each arm and the DC-side switch SW _D and AC-side switch SW _U matrix converter A by the control unit 13b, by SW _V, the control of the SW _W is carried out, The power converter 10b can perform power conversion between AC and DC in a state where the voltage converter or the current converter is appropriately selected.

FIG. 4 is a diagram illustrating the switching control state of each arm of the matrix converter A and the DC side switch SW _D and the AC side switches SW _U , SW _V , SW _W in the bidirectional power converter 10b of the second embodiment. 4A shows a switching control state when used as a current type, and FIG. 4B shows a switching control state when used as a voltage type.

In the bidirectional power converter 10b of the second embodiment, the control unit 13b uses the DC-side inductor L _D when used as a current source (for example, when the AC-side voltage is larger than the DC-side voltage). and a parallel DC-side switch SW _D is turned off, and the AC-side capacitor C _U, C _V, C _W series with AC side switch SW _U, SW _V, and all the SW _W on (FIGS. 4 (a) reference).

On the other hand, when used as a voltage type (for example, when the voltage on the AC side is smaller than the voltage on the DC side), the DC side switch SW _D parallel to the DC side inductor L _D is turned on, and the AC side All the AC side switches SW _U , SW _V , SW _W in series with the capacitors C _U , C _V , C _W are turned off (see FIG. 4B).

In bidirectional power converter 10b of the second embodiment described above, as shown in FIG. 4 (a), the current to the DC-side inductor L _D in parallel with the DC-side switch SW _D OFF (DC side inductor L _D a state) that passes through, and the AC-side capacitor C _U, C _V, C _W series with AC side switch SW _U, SW _V, all SW _W on (AC side capacitor C _U, C _V, current C _W Circuit state to be configured as a current type, that is, from the DC side to the AC side, “DC power supply Gb” → “DC inductor L _D ” → “matrix converter A” → “AC capacitor It becomes possible to realize a circuit configuration of “C _U , C _V , C _W ” → “AC motor Eb”.

Further, as shown in FIG. 4B, the DC side switch SW _D parallel to the DC side inductor L _D is turned on (the current does not pass through the DC side inductor L _D ), and the AC side capacitors C _U , By configuring all AC side switches SW _U , SW _V , SW _W in series with C _V , C _W to be off (state in which no current passes through the AC side capacitors C _U , C _V , C _W ), it is configured as a voltage type The circuit configuration to be realized, that is, the circuit configuration of “DC power supply Gb” → “matrix converter A” → “AC motor Eb” from the DC side to the AC side can be realized.

  As described above, according to the bidirectional power converter 10b of the second embodiment, the current type and the voltage type can be properly used by one bidirectional power converter 10b. Can be easily used without being conscious of the magnitude relationship between the voltage on the AC side and the voltage on the AC side (for example, without providing a circuit for stepping up or down the voltage on the DC side).

(Third embodiment)
Next, a case where the bidirectional power converter according to the third embodiment of the present invention is used as a grid interconnection inverter will be described as an example.

  FIG. 5 is a circuit diagram showing a schematic configuration of the bidirectional power converter 10c according to the third embodiment. The bidirectional power converter 10c shown in FIG. 5 controls the matrix converter A, the DC side circuit 11b of the matrix converter A, the AC side circuit 12a of the matrix converter A, and the entire bidirectional power converter 10c. And a control unit 13c.

  Hereinafter, the bidirectional power converter 10c of the third embodiment will be described focusing on differences from the bidirectional power converter 10a of the first embodiment. In FIG. 5, the same components as those of the bidirectional power converter 10a of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The DC side circuit 11b of the matrix converter A has a DC power source Ga connected to the input side and a matrix converter A connected to the output side.

The DC side circuit 11b includes a DC side inductor L _D connected in series to the connection line on at least one of the plus terminal side and the minus terminal side of the DC power supply Ga (here, the plus terminal side). Is provided.

Further, a series circuit F connected in parallel with the DC power source Ga is provided between the DC side inductor L _D and the matrix converter A. Series circuit F is to a direct current side capacitor C _D and the DC-side switch SW _D are connected in series.

In bidirectional power converter 10c having such a configuration, each arm and the DC-side switch SW _D and AC-side switch SW _U matrix converter A by the control unit 13c, by SW _V, the control of the SW _W is carried out, It is possible to perform power conversion between AC and DC in a state where the power converter 10c is of a voltage type or a current type is appropriately selected.

FIG. 6 is a diagram illustrating a switching control state of each arm of the matrix converter A and the DC side switch SW _D and the AC side switches SW _U , SW _V , SW _W in the bidirectional power converter 10c of the third embodiment. 6A shows a switching control state when used as a current type, and FIG. 6B shows a switching control state when used as a voltage type.

In the bidirectional power converter 10c according to the third embodiment, when the control unit 13c is used as a current source (for example, when the AC side voltage is larger than the DC side voltage), the DC side capacitor C the _D series with the DC-side switch SW _D is turned off, and the AC side inductor L _U, L _V, L _W parallel with the AC side switch SW _U, SW _V, and all the SW _W on (FIG. 6 (a )reference).

On the other hand, when used as a voltage type (e.g., when the voltage on the AC side is smaller than the voltage of the DC side), the turns on the DC side capacitor C _D series with the DC-side switch SW _D, and AC side All the AC side switches SW _U , SW _V , SW _W in parallel with the inductors L _U , L _V , L _W are turned off (see FIG. 6B).

In bidirectional power converter 10c of the third embodiment described above, as shown in FIG. 6 (a), the current to the DC side capacitor C _D series with the DC-side switch SW _D OFF (DC side capacitor C _D and does not state) and the passage, and the AC side inductor L _U, L _V, L _W parallel with the AC side switch SW _U, SW _V, SW _W all on (AC side inductor L _U, L _V, current L _W Circuit state to be configured as a current type, that is, from the DC side to the AC side, “DC power supply Ga” → “DC inductor L _D ” → “matrix converter A” → “AC side system” The circuit configuration of “Ea” can be realized.

Further, as shown in FIG. 6 (b), the DC side capacitor C _D series with the DC-side switch SW _D on (state current to the DC side capacitor C _D passes), and the AC side inductor L _U, The AC side switches SW _U , SW _V , and SW _W in parallel with L _V and L _W are all turned off (current is passed through the AC side inductors L _U , L _V , and L _W ) to form a voltage type From the DC side to the AC side, “DC power supply Ga” → “DC side inductor L _D ” → “DC side capacitor C _D ” → “matrix converter A” → “AC side inductors L _U , L _V , The circuit configuration of “L _W ” → “AC side system Ea” can be realized.

  As described above, according to the bidirectional power converter 10c of the third embodiment, the current type and the voltage type can be selectively used by one bidirectional power converter 10c, as in the first and second embodiments. .

(Fourth embodiment)
Next, regarding the bidirectional power converter according to the fourth embodiment of the present invention, when converting power from direct current to alternating current, as a motor drive inverter, and when converting power from alternating current to direct current, A case of using as a machine rectifier converter will be described as an example.

  FIG. 7 is a circuit diagram showing a schematic configuration of a bidirectional power converter 10d according to the fourth embodiment. The bidirectional power converter 10d shown in FIG. 7 controls the matrix converter A, the DC side circuit 11b of the matrix converter A, the AC side circuit 12b of the matrix converter A, and the entire bidirectional power converter 10d. And a control unit 13d.

  Hereinafter, the bidirectional power converter 10d of the fourth embodiment will be described focusing on differences from the bidirectional power converter 10b of the second embodiment. In FIG. 7, the same components as those of the bidirectional power converter 10b of the second embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The DC side circuit 11b of the matrix converter A has a DC power supply Gb connected to the input side and a matrix converter A connected to the output side.

The DC side circuit 11b includes a DC side inductor L _D connected in series to at least one of the plus terminal side and the minus terminal side (here, the plus terminal side) of the DC power supply Gb with respect to the connection line. Is provided.

Further, between the DC side inductor L _D and the matrix converter A, the series circuit F is provided which is connected in parallel with the DC power supply Gb. Series circuit F is to a direct current side capacitor C _D and the DC-side switch SW _D are connected in series.

In bidirectional power converter 10d having such a configuration, each arm and the DC-side switch SW _D and AC-side switch SW _U matrix converter A by the control unit 13d, by SW _V, the control of the SW _W is carried out, It is possible to perform power conversion between AC and DC in a state where the power converter 10d is of a voltage type or a current type is appropriately selected.

FIG. 8 is a diagram illustrating the switching control state of each arm of the matrix converter A and the DC side switch SW _D and the AC side switches SW _U , SW _V , SW _W in the bidirectional power converter 10d of the fourth embodiment. FIG. 8A shows the switching control state when used as a current type, and FIG. 8B shows the switching control state when used as a voltage type.

In the bidirectional power converter 10d of the fourth embodiment, the control unit 13d uses the DC side capacitor C _D when used as a current source (for example, when the AC side voltage is larger than the DC side voltage). a series DC-side switch SW _D is turned off, and the AC-side capacitor C _U, C _V, C _W series with AC side switch SW _U, SW _V, and all the SW _W on (see FIG. 8 (a) reference).

On the other hand, when used as a voltage type (e.g., when the voltage on the AC side is smaller than the voltage of the DC side), the turns on the DC side capacitor C _D series with the DC-side switch SW _D, and AC side All the AC side switches SW _U , SW _V , SW _W in series with the capacitors C _U , C _V , C _W are turned off (see FIG. 8B).

In bidirectional power converter 10d of the fourth embodiment described above, as shown in FIG. 8 (a), the current to the DC side capacitor C _D series with the DC-side switch SW _D OFF (DC side capacitor C _D and does not state) and the passage, and the AC-side capacitor C _U, C _V, C _W series with AC side switch SW _U, SW _V, all SW _W on (AC side capacitor C _U, C _V, current C _W Circuit state to be configured as a current type, that is, from the DC side to the AC side, “DC power supply Gb” → “DC inductor L _D ” → “matrix converter A” → “AC capacitor It becomes possible to realize a circuit configuration of “C _U , C _V , C _W ” → “AC motor Eb”.

Further, as shown in FIG. 8 (b), the DC side capacitor C _D series with the DC-side switch SW _D on (state current to the DC side capacitor C _D passes), and the AC-side capacitor C _U, By configuring all AC side switches SW _U , SW _V , SW _W in series with C _V , C _W to be off (state in which no current passes through the AC side capacitors C _U , C _V , C _W ), it is configured as a voltage type From the DC side to the AC side, the circuit configuration of “DC power supply Gb” → “DC side inductor L _D ” → “DC side capacitor C _D ” → “matrix converter A” → “AC side motor Eb” It can be realized.

  As described above, according to the bidirectional power converter 10d of the fourth embodiment, the current type and the voltage type can be selectively used by one bidirectional power converter 10d, as in the first to third embodiments. .

  Next, in the bidirectional power converters 10a to 10d of the first to fourth embodiments, the switching operation of the matrix converter A when the current type is used, and the switching of the matrix converter A when the voltage type is used. The operation will be described below with reference to FIGS. 2, 4, 6 and 8.

[When used as a current source]
FIGS. 2A and 6A show the switching operation of the matrix converter A when power is supplied from the DC side to the AC side. FIGS. 4A and 8A show the switching operation of the matrix converter A when power is supplied from the AC side to the DC side.

  In the bidirectional power converters 10a to 10d of the first embodiment to the fourth embodiment, the control units 13a to 13d are respectively connected from the direct current side to the alternating current side as shown in FIGS. 2 (a) and 6 (a). When power is supplied to any one of the phase lines U, V, W, the switches (S1a, S1b), ( Of S2a, S2b) and (S3a, S3b), switches S1a, S2a, S3a that conduct from the DC side to the AC side are switched, while switches S1b, S2b, S3b that conduct from the AC side to the DC side are always off. Of the switches (S6a, S6b), (S5a, S5b), (S4a, S4b) constituting the lower arms C6, C5, C4, the switch S6 that conducts from the DC side to the AC side , S5a, while always off S4a, switch S6b to conduct from the AC side to the DC side, S5b, switching the S4b.

  4 (a) and 8 (a), although not shown, when power is supplied from the DC side to the AC side, FIGS. 2 (a) and 6 (a). The same operation as the switching operation shown in FIG.

  On the other hand, as shown in FIG. 4 (a) and FIG. 8 (a), when power is supplied from one of the lines U, V, W of each phase on the AC side to the DC side, it corresponds. Of the switches (S1a, S1b), (S2a, S2b), (S3a, S3b) constituting the upper arms C1, C2, C3 of the lines U, V, W, switches S1b, S2b that conduct from the AC side to the DC side , S3b are switched, while switches S1a, S2a, S3a conducting from the DC side to the AC side are always turned off, and lower arms (S6a, S6b), (S5a, S5b), (S4a, S4b) are configured. Among the switches, the switches S6b, S5b, and S4b that conduct from the AC side to the DC side are always turned off, while the switches S6a, S5a, and S4a that conduct from the DC side to the AC side are switched off. Ring to.

  Although not shown in the configurations shown in FIGS. 2A and 6A, when power is supplied from the AC side to the DC side, FIGS. 4A and 8A are used. The same operation as the switching operation shown in FIG.

  Thus, based on the circuit configuration in which the bidirectional power converters 10a to 10d are current sources, by performing switching control considering the conduction direction of each switch in the matrix converter A according to the direction of supplying power, Power supply from the DC side to the AC side or from the AC side to the DC side in the current source operation mode (here, the interconnection with the system Ea in the first and third embodiments, the motor in the second and fourth embodiments) Eb driving or charging of the storage battery or capacitor Gb) can be performed satisfactorily.

[When using as a voltage type]
FIGS. 2B and 6B show the switching operation of the matrix converter A when the direction of the current flowing through the lines U, V, and W of each phase is the direction from the DC side to the AC side. . FIGS. 4B and 8B show the switching operation of the matrix converter A when the direction of the current flowing through the lines U, V, W of each phase is the direction from the AC side to the DC side. ing.

  In the bidirectional power converters 10a to 10d of the first embodiment to the fourth embodiment, the control units 13a to 13d are related to the direction of the current flowing in each of the lines U, V, and W of each phase on the AC side. As shown in FIGS. 2B and 6B, in the direction from the DC side to the AC side, the switches (S1a) constituting the upper arms C1, C2, C3 of the corresponding lines U, V, W , S1b), (S2a, S2b), (S3a, S3b), switches S6a, S5a, S4a conducting from the DC side to the AC side, and switches S6b, S5b conducting from the AC side to the DC side. Of the switches (S6a, S6b), (S5a, S5b), and (S4a, S4b) that constitute the lower arms C6, C5, and C4, the S4b is always turned off. Switch S6a that conduct to the side, S5a, while regularly on the S4a, switch S6b to conduct from the AC side to the DC side, S5b, it is always turned off S4b.

  4B and 8B, although not shown, when the direction of the current flowing through the lines U, V, W of each phase is the direction from the DC side to the AC side, The same operation as the switching operation shown in FIGS. 2B and 6B is performed.

  On the other hand, as shown in FIGS. 4B and 8B, in the direction from the AC side to the DC side, the switches constituting the lower arms C6, C5, C4 of the corresponding lines U, V, W Among (S6a, S6b), (S5a, S5b), (S4a, S4b), the switch S6b, S5b, S4b that conducts from the AC side to the DC side is switched, while the switch S6a that conducts from the DC side to the AC side S5a, S4a are always off, and among the switches (S1a, S1b), (S2a, S2b), (S3a, S3b) constituting the upper arms C1, C2, C3, a switch conducting from the AC side to the DC side S1b, S2b, and S3b are always turned on, while switches S1a, S2a, and S3a that conduct from the DC side to the AC side are always turned off.

  In the configurations shown in FIGS. 2B and 6B, although not shown, when the direction of the current flowing through the lines U, V, W of each phase is the direction from the AC side to the DC side, The same operation as the switching operation shown in FIGS. 4B and 8B is performed.

  Here, when used as a voltage type, the direction of the current flowing through the lines U, V, W of each phase by the control units 13a to 13d is identified by, for example, a current for detecting the current flowing through the lines U, V, W. This can be done by recognizing the detected value of a sensor (not shown) and the direction of the current flowing through each line U, V, W that can be determined from the switching control configuration.

  As described above, based on the circuit configuration in which the bidirectional power converters 10a to 10d are in voltage form, the conduction direction of each switch in the matrix converter A is considered according to the direction of the current flowing through each line U, V, W. By performing switching control, bidirectional power conversion in the voltage-type operation mode (here, interconnection with the system Ea in the first and third embodiments, the motor Eb in the second and fourth embodiments) Driving or charging the storage battery or capacitor Gb) can be performed satisfactorily.

  The bidirectional switches C1, C2, C3, C4, C5, and C6 used in the bidirectional power converters 10a to 10d of the first to fourth embodiments (S1a, S1b) to (S6a, S6b). ) Is a reverse blocking type IGBT, but as shown in FIG. 9, the reverse blocking characteristic in which the diode 200 is connected in series with the IGBT 100 so as to be opposite to the conduction direction of the diode 110 in the IGBT 100 is shown. It is good also as another semiconductor element which shows IGBT to show or reverse blocking characteristics.

  Moreover, although the bidirectional | two-way power converter 10a-10d of 1st Embodiment-4th Embodiment is a thing of a three phase structure, it is good also as a thing of other phase structures, for example, a thing of a single phase structure. In the case of this single phase configuration, in the bidirectional power converters 10a and 10c of the first and third embodiments, the AC side inductor can be provided in each phase or any one phase.

Further, in the bidirectional power converters 10b and 10d of the second and fourth embodiments, the AC-side capacitors C _U , C _V , and C _W that are Y-connected to the phases U, V, and W of the AC line A series circuit comprising AC side switches SW _U , SW _V , SW _W is provided, but instead, between each phase U, V, between each phase V, W, between each phase W, U of the AC line. Such a series circuit may be provided.

It is a circuit diagram which shows schematic structure of the bidirectional | two-way power converter which concerns on 1st Embodiment. It is a figure which shows the switching control state of each arm of a matrix converter in a bidirectional | two-way power converter of 1st Embodiment, a DC side switch, and an AC side switch, Comprising: FIG. It is a figure which shows a state, and a figure (b) is a figure which shows the switching control state in the case of using as a voltage form. It is a circuit diagram which shows schematic structure of the bidirectional | two-way power converter which concerns on 2nd Embodiment. It is a figure which shows the switching control state of each arm of a matrix converter in a bidirectional | two-way power converter of 2nd Embodiment, a DC side switch, and an AC side switch, Comprising: FIG. It is a figure which shows a state, and a figure (b) is a figure which shows the switching control state in the case of using as a voltage form. It is a circuit diagram which shows schematic structure of the bidirectional | two-way power converter which concerns on 3rd Embodiment. It is a figure which shows the switching control state of each arm of a matrix converter in a bidirectional | two-way power converter of 3rd Embodiment, and a DC side switch and an AC side switch, Comprising: FIG. It is a figure which shows a state, and a figure (b) is a figure which shows the switching control state in the case of using as a voltage form. It is a circuit diagram which shows schematic structure of the bidirectional | two-way power converter which concerns on 4th Embodiment. It is a figure which shows the switching control state of each arm of a matrix converter in a bidirectional | two-way power converter of 4th Embodiment, and a DC side switch and an AC side switch, Comprising: FIG. It is a figure which shows a state, and a figure (b) is a figure which shows the switching control state in the case of using as a voltage form. It is a figure which shows the other example of each switch in the bidirectional | two-way switch used for the bidirectional | two-way power converter of 1st Embodiment to 4th Embodiment.

Explanation of symbols

10a bidirectional power converter A matrix converter C1~C4 bidirectional switch C1~C3 upper arm C4~C6 lower arm C _D DC side capacitor C _U, C _V, C _W AC side capacitor Ga DC power L _D DC side inductor L _U, L _V, L _W AC side inductor S1a~S6a one S1b~S6b bidirectional switch of the other SW _D DC side switch SW _U bidirectional switches, SW _V, SW _W AC side switches U, V, and W AC side Line for each phase

Claims (7)

In the bidirectional power converter that performs mutual power conversion between AC and DC by a matrix converter that uses a bidirectional switch composed of a pair of switches whose conduction directions are opposite to each other as the upper and lower arms of each phase,
Provide a DC side inductor on both or one of the positive terminal side and negative terminal side of the DC power source connected to the DC side,
In the case of each phase or single phase of the AC line, an AC side inductor is provided for each phase or any one phase,
A DC switch is provided in parallel with the DC inductor,
An AC switch is provided in parallel with the AC inductor,
When used as a current source, turn off the DC side switch in parallel with the DC side inductor, and turn on all the AC side switches in parallel with the AC side inductor,
When used as a voltage type, the bidirectional power converter is characterized in that the direct current side switch parallel to the direct current side inductor is turned on and the alternating current side switch parallel to the alternating current side inductor is turned off. . In the bidirectional power converter that performs mutual power conversion between AC and DC by a matrix converter that uses a bidirectional switch composed of a pair of switches whose conduction directions are opposite to each other as the upper and lower arms of each phase,
Provide an inductor on both or one of the positive terminal side and negative terminal side of the DC power source connected to the DC side,
A capacitor is provided between each phase of the AC line, or a Y-connected capacitor is provided for each phase of the AC line,
A DC side switch is provided in parallel with the inductor,
An AC side switch is provided in series with the capacitor,
When used as a current source, turn off the DC side switch in parallel with the inductor, and turn on all the AC side switches in series with the capacitor,
When used as a voltage type, a bidirectional power converter characterized in that the DC side switch in parallel with the inductor is turned on and all the AC side switches in series with the capacitor are turned off. In the bidirectional power converter that performs mutual power conversion between AC and DC by a matrix converter that uses a bidirectional switch composed of a pair of switches whose conduction directions are opposite to each other as the upper and lower arms of each phase,
Provide a DC side inductor on both or one of the positive terminal side and negative terminal side of the DC power source connected to the DC side,
Between the DC inductor and the matrix converter, a series circuit composed of a capacitor and a DC switch is provided in parallel with the DC power supply,
In the case of each phase or single phase of the AC line, an AC side inductor is provided for each phase or any one phase,
An AC switch is provided in parallel with the AC inductor,
When used as a current source, turn off the DC side switch in series with the capacitor, and turn on all the AC side switches in parallel with the AC side inductor,
When used as a voltage type, a bidirectional power converter characterized in that the DC side switch in series with the capacitor is turned on, and all the AC side switches in parallel with the AC side inductor are turned off. In the bidirectional power converter that performs mutual power conversion between AC and DC by a matrix converter that uses a bidirectional switch composed of a pair of switches whose conduction directions are opposite to each other as the upper and lower arms of each phase,
Provide an inductor on both or one of the positive terminal side and negative terminal side of the DC power source connected to the DC side,
Between the inductor and the matrix converter, a series circuit composed of a DC capacitor and a DC switch is provided in parallel with the DC power supply,
Provide a series circuit consisting of an AC side capacitor and an AC side switch between each phase of the AC line, or provide a series circuit consisting of an AC side capacitor and an AC side switch Y-connected to each phase of the AC line,
When used as a current source, turn off the DC side switch in series with the DC side capacitor, and turn on all the AC side switches in series with the AC side capacitor,
When used as a voltage type, a bidirectional power converter characterized in that the DC side switch in series with the DC side capacitor is turned on, and all the AC side switches in series with the AC side capacitor are turned off. . The bidirectional power converter according to any one of claims 1 to 4,
When using as a current source, when supplying power from the DC side to the AC side,
Among the switches constituting the upper arm of each phase of the matrix converter, the switch that conducts from the DC side to the AC side is switched, while the switch that conducts from the AC side to the DC side is always off, and the switch of the matrix converter Of the switches constituting the lower arm of each phase, the switch that conducts from the DC side to the AC side is always off, while the switch that conducts from the AC side to the DC side is switched. . The bidirectional power converter according to any one of claims 1 to 4,
When using as a current source, when supplying power from the AC side to the DC side,
Of the switches constituting the upper arm of each phase of the matrix converter, the switch that conducts from the AC side to the DC side is switched, while the switch that conducts from the DC side to the AC side is always off, and the matrix converter Of the switches constituting the lower arm of each phase, the switch that conducts from the AC side to the DC side is always off, while the switch that conducts from the DC side to the AC side is switched. . The bidirectional power converter according to any one of claims 1 to 4,
When used as a voltage type, regarding the direction of the current flowing in each phase of the AC line,
When the direction is from the DC side to the AC side, among the switches constituting the upper arm of the matrix converter, the switch that conducts from the DC side to the AC side is switched, while the switch from the AC side to the DC side is conducted. Of the switches that constitute the lower arm of the phase of the matrix converter, the switch that is always off and the switch that conducts from the DC side to the AC side is always on, while the switch that conducts from the AC side to the DC side Always off,
When the direction is from the AC side to the DC side, among the switches constituting the lower arm of the matrix converter in question, the switch that conducts from the AC side to the DC side is switched, while the switch from the DC side to the AC side is conducted. Of the switches constituting the upper arm of the matrix converter in which the switch is always off, the switch that conducts from the AC side to the DC side is always on, while the switch that conducts from the DC side to the AC side Bidirectional power converter characterized by being always off.

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