Power conversion device

Abstract

To suppress current unbalance of a plurality of semiconductor modules connected in parallel.SOLUTION: A power conversion device includes: a plurality of semiconductor modules each including two switching elements connected in series, disposed side by side in a first direction and connected in parallel; an AC wire extending in the first direction and commonly connecting AC terminals of the plurality of semiconductor modules; and an AC lead-out wire extending in the first direction and configured to lead out the AC wire to an output terminal. The AC lead-out wire includes a connection portion, which is connected to the AC wire, and an extension portion which is disposed in parallel with the AC wire. A center of the connection portion of the AC lead-out wire in the first direction is set to a side which is farther from the output terminal, than a center of the whole plurality of semiconductor modules in the first direction.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] Embodiments of the present invention relate to a power conversion device.

Background Art

[0002] A power conversion device is used in a converter and an inverter that drive an elevator hoist. The power conversion device includes a semiconductor module having two switching elements (for example, IGBTs) connected in series for each phase of three-phase AC power. In a power conversion device for high speed and large capacity, a plurality of semiconductor modules are connected in parallel and used.

[0003] Conventionally, AC terminals of a plurality of semiconductor modules connected in parallel are connected together with equal-length wiring, and an output terminal is drawn out from the power conversion device. In this case, since an inductance difference occurs in a plurality of wirings connected to the plurality of semiconductor modules, current tends to be biased to the semiconductor module on the side closer to the output terminal. That is, since the inductance of the semiconductor module closest to the output terminal is small, the current becomes large, and since the inductance of the semiconductor module farthest from the output terminal is large, the current becomes small.

[0004] Even if the characteristics of a plurality of semiconductor modules connected in parallel are uniform, an inductance difference occurs in the plurality of semiconductor modules due to the wiring structure, resulting in current imbalance. Due to the current imbalance, heat generation of a specific semiconductor module increases, leading to a decrease in the efficiency of the power conversion device. In addition, a specific semiconductor module may fail due to thermal fatigue life.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The problem to be solved by the present invention is to provide a power conversion device capable of suppressing current imbalance in a plurality of semiconductor modules connected in parallel.

Means for Solving the Problem

[0007] The power conversion device according to the embodiment has two switching elements connected in series, respectively, arranged side by side in the first direction, a plurality of semiconductor modules connected in parallel, an AC wiring extending in the first direction and commonly connecting the AC terminals of the plurality of semiconductor modules, and an AC lead-out wiring extending in the first direction and configured to lead out the AC wiring to an output terminal. The AC lead-out wiring has a connection portion connected to the AC wiring and an extending portion arranged side by side with the AC wiring. The center of the connection portion of the AC lead-out wiring in the first direction is set on the side farther from the output terminal than the center of the plurality of semiconductor modules as a whole in the first direction.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments will be described with reference to the drawings. Several embodiments shown below are examples of devices and methods for embodying the technical idea of the present invention, and the technical idea of the present invention is not specified by the shape, structure, arrangement, etc. of the constituent parts. In the following description, elements having the same function and configuration are denoted by the same reference numerals, and overlapping descriptions are omitted.

[0010] [1] First Embodiment [1-1] Configuration of Power Conversion Device 1 FIG. 1 is a circuit diagram of the power conversion device 1 according to the first embodiment. The power conversion device 1 in FIG. 1 is a single-phase device of a converter or an inverter. For example, when configuring an inverter, the devices in FIG. 1 are used in parallel connection for three phases.

[0011] The power conversion device 1 includes a plurality of semiconductor modules 10, connection wirings 20, 21, an AC wiring 22, an AC lead-out wiring 23, an output terminal 13, a positive terminal 14, a negative terminal 15, and a capacitor 16.

[0012] In FIG. 1, four semiconductor modules 10-1 to 10-4 are shown as an example. The semiconductor modules 10-1 to 10-4 are connected in parallel between the positive terminal 14 and the negative terminal 15. The semiconductor modules 10-1 to 10-4 have the same configuration. The number of semiconductor modules 10 is not limited to four and can be set to any number of two or more. In the following description, when there is no need to distinguish between the semiconductor modules 10-1 to 10-4, the subscript is omitted and they are denoted as the semiconductor module 10, and the description of the semiconductor module 10 is common to the four semiconductor modules 10-1 to 10-4. The same applies to other reference numerals with subscripts.

[0013] The semiconductor module 10 includes two switching elements 11-1, 11-2, a positive power supply terminal T1, a negative power supply terminal T2, and an AC terminal T3.

[0014] The positive power supply terminal T1 is connected to the positive terminal 14. The negative power supply terminal T2 is connected to the negative terminal 15. The AC terminal T3 is connected to the connection wirings 20, 21. The AC terminal T3 is a terminal for outputting AC power.

[0015] The switching element 11 is composed of, for example, a SiC power MOSFET (Metal Oxide Semiconductor Field Effect Transistor) and is an N-channel MOSFET. The SiC power MOSFET is a compound semiconductor and is a MOSFET using SiC as a substrate. The switching element may be a MOSFET other than SiC, a bipolar transistor, or an IGBT (Insulated Gate Bipolar Transistor).

[0016] The switching elements 11-1, 11-2 are connected in series between the positive power supply terminal T1 and the negative power supply terminal T2. Specifically, the drain of the switching element 11-1 is connected to the positive power supply terminal T1. The source of the switching element 11-1 is connected to the AC terminal T3. The drain of the switching element 11-2 is connected to the AC terminal T3. The source of the switching element 11-2 is connected to the negative power supply terminal T2.

[0017] Diodes 12-1, 12-2 are connected in anti-parallel to the switching elements 11-1, 11-2 respectively. The diode 12 is a freewheeling diode and has a function of protecting the switching element 11 when a reverse current is supplied to the switching element 11. The diode 12 is composed of a parasitic diode of the transistor. The diode 12 may be provided separately and connected in anti-parallel to the switching element 11.

[0018] In FIG. 1, the gate terminal, source terminal, and drain terminal of the MOSFET are indicated by white circles without reference numerals. The gate terminal, source terminal, and drain terminal of the MOSFET are connected to a control circuit (not shown), and their potentials are controlled.

[0019] The connection wiring 20 connects the AC terminal T3 of the semiconductor module 10-1 and the AC terminal T3 of the semiconductor module 10-2. The connection wiring 21 connects the AC terminal T3 of the semiconductor module 10-3 and the AC terminal T3 of the semiconductor module 10-4. The AC wiring 22 connects the connection wiring 20 and the connection wiring 21. The AC wiring 22 is connected to the AC lead-out wiring 23.

[0020] The AC lead-out wiring 23 is connected to the output terminal 13. The output terminal 13 is a terminal connected to an external AC power line or an AC load. When the power conversion device 1 is used as an inverter, the output terminal 13 outputs AC power.

[0021] The positive terminal 14 is a terminal connected to an external positive power line. A positive power supply is supplied to the positive terminal 14. The negative terminal 15 is a terminal connected to an external negative power line. A negative power supply is supplied to the negative terminal 15.

[0022] The capacitor 16 is connected between the positive terminal 14 and the negative terminal 15. The capacitor 16 has a function of smoothing the voltage.

[0023] [1-2] Wiring Structure of Power Conversion Device 1 Next, the wiring structure of the power conversion device 1 will be described.

[0024] FIG. 2 is a perspective view showing the wiring structure of the power conversion device 1. In FIG. 2, the X direction is the direction in which the plurality of semiconductor modules 10 are arranged side by side, the Y direction is the direction orthogonal to the X direction in the plane, and the Z direction is the direction orthogonal to the XY plane. The semiconductor modules 10-1 to 10-4 are arranged side by side in the X direction.

[0025] The AC terminal T3 of the semiconductor module 10-1 and the AC terminal T3 of the semiconductor module 10-2 are connected by a connection wiring 20. Specifically, the connection wiring 20 is configured by connecting an extending portion 20A extending in the X direction, a protruding portion 20B protruding in the Z direction, and an extending portion 20C extending in the X direction in this order. The protruding portion 20B has an inverted U shape. The extending portion 20A of the connection wiring 20 is connected to the AC terminal T3 of the semiconductor module 10-1 and fixed to the AC terminal T3 by a screw (not shown). The extending portion 20C of the connection wiring 20 is connected to the AC terminal T3 of the semiconductor module 10-2 and fixed to the AC terminal T3 by a screw (not shown).

[0026] The AC terminal T3 of the semiconductor module 10-3 and the AC terminal T3 of the semiconductor module 10-4 are connected by a connection wiring 21. Specifically, the connection wiring 21 is configured by connecting an extending portion 21A extending in the X direction, a protruding portion 21B protruding in the Z direction, and an extending portion 21C extending in the X direction in this order. The protruding portion 21B has an inverted U shape. The extending portion 21A of the connection wiring 21 is connected to the AC terminal T3 of the semiconductor module 10-3 and fixed to the AC terminal T3 by a screw (not shown). The extending portion 21C of the connection wiring 21 is connected to the AC terminal T3 of the semiconductor module 10-4 and fixed to the AC terminal T3 by a screw (not shown).

[0027] The AC wiring 22 is a wiring extending in the X direction. The AC wiring 22 connects the connection wiring 20 and the connection wiring 21. Specifically, one end of the AC wiring 22 is connected to the protruding portion 20B of the connection wiring 20 and fixed to the protruding portion 20B by a screw (not shown). The other end of the AC wiring 22 is connected to the protruding portion 21B of the connection wiring 21 and fixed to the protruding portion 21B by a screw (not shown).

[0028] The AC extraction wiring 23 is a wiring extending in the X direction. The AC extraction wiring 23 connects the AC wiring 22 and the output terminal 13. The AC extraction wiring 23 is configured to be drawn out from the AC wiring 22 in the Z direction and extend in the X direction. The AC extraction wiring 23 includes a connection portion 23A connected to the AC wiring 22 and an extending portion 23B extending in the X direction from the connection portion 23A. The connection portion 23A is configured to include a curved portion drawn out in the Z direction. The extending portion 23B is arranged side by side with the AC wiring 22.

[0029] Here, a line passing through the center of the AC wiring 22 in the X direction is referred to as a center line C1. A line passing through the center of the connection portion 23A of the AC extraction wiring 23 in the X direction is referred to as a center line C2. The center line C1 has the same meaning as a line passing through the center of the entire semiconductor modules 10-1 to 10-4 in the X direction.

[0030] In this embodiment, the center line C2 of the connection portion 23A of the AC extraction wiring 23 is set to be shifted to the side farther from the output terminal 13 from the center line C1 of the AC wiring 22. In other words, the AC extraction wiring 23 is connected to the AC wiring 22 while being shifted to the side farther from the output terminal 13 from the center of the AC wiring 22 in the X direction.

[0031] The AC wiring 22 and the AC extraction wiring 23 may be configured by electrically connecting individual members or may be configured by integral molding.

[0032] [1-3] Operation The operation of the power conversion device 1 configured as described above will be described.

[0033] DC power is supplied to the positive terminal 14 and the negative terminal 15 from the outside. A positive-side power supply is supplied to the positive terminal 14, and a negative-side power supply is supplied to the negative terminal 15.

[0034] A gate voltage is applied from a control circuit (not shown) to the gates of the switching elements 11-1 and 11-2 included in the semiconductor module 10-1. The switching elements 11-1 and 11-2 perform a switching operation. The semiconductor modules 10-2 to 10-4 connected in parallel with the semiconductor module 10-1 also execute the same operation as the semiconductor module 10-1. Thereby, the power conversion device 1 can output single-phase AC power from the output terminal 13.

[0035] As shown in FIG. 2, the AC current of the semiconductor module 10-1 closest to the output terminal 13 flows through the AC lead-out wiring 23 from the AC wiring 22. The AC current flowing from the semiconductor module 10-1 to the AC wiring 22 and the AC current flowing through the AC lead-out wiring 23 are opposite in direction to each other and face each other. Therefore, since it acts in a direction to reduce the inductance due to mutual induction, the current of the semiconductor module 10-1 increases.

[0036] On the other hand, the AC current of the semiconductor module 10-4 farthest from the output terminal 13 also flows through the AC lead-out wiring 23 from the AC wiring 22 in the same manner. The AC current flowing from the semiconductor module 10-4 to the AC wiring 22 and the AC current flowing through the AC lead-out wiring 23 do not face each other. Therefore, there is almost no mutual induction and it does not contribute to the increase or decrease of the inductance. Therefore, the inductance of the semiconductor module 10-4 is larger than that of the semiconductor module 10-1.

[0037] The inductances of the semiconductor modules 10-2 and 10-3 are in the middle between the semiconductor module 10-1 and the semiconductor module 10-4.

[0038] Here, by configuring the wiring structure as shown in FIG. 2, the wiring path of the semiconductor module 10-4 can be shortened, and thereby the inductance from the semiconductor module 10-4 to the output terminal 13 can be reduced. On the other hand, the wiring path of the semiconductor module 10-1 becomes longer, but due to mutual induction, there is almost no increase or decrease in inductance. That is, the current imbalance can be reduced from the effect of suppressing the inductance difference of the four parallel semiconductor modules.

[0039] [1-4] Comparative Example Next, the configuration of the comparative example will be described. FIG. 3 is a perspective view showing the wiring structure of the power conversion device according to the comparative example.

[0040] The power conversion device includes semiconductor modules 10-1 to 10-4 connected in parallel. The AC wiring 22 connects the connection wiring 20 and the connection wiring 21. The AC lead-out wiring 23 connects the AC wiring 22 and the output terminal 13.

[0041] In the comparative example, the AC lead-out wiring 23 is connected to the AC wiring 22 at the center of the AC wiring 22. That is, the center line C1 of the AC wiring 22 is set at the same position as the center line C2 of the connection portion of the AC lead-out wiring 23.

[0042] In the semiconductor module 10-1 closest to the output terminal 13, the mutual induction acts in a direction to reduce the inductance, so the current flowing through the semiconductor module 10-1 increases. On the other hand, in the semiconductor module 10-4 farthest from the output terminal 13, there is almost no mutual induction, and since the wiring path is long, the inductance increases. Also, the current tends to be biased among the semiconductor modules 10-1 to 10-4 according to the distance from the output terminal 13. As a result, in the comparative example, the imbalance of the output currents of the semiconductor modules 10-1 to 10-4 increases.

[0043] On the other hand, in the present embodiment, compared with the comparative example, the inductance difference between the parallel-connected semiconductor modules 10-1 to 10-4 can be reduced, so the imbalance of the output currents of the semiconductor modules 10-1 to 10-4 can be reduced.

[0044] [1-5] Effects of the First Embodiment According to the first embodiment, since the inductance difference between the parallel-connected semiconductor modules 10-1 to 10-4 can be reduced, the imbalance of the output currents of the semiconductor modules 10-1 to 10-4 can be reduced. In addition, an increase in the heat generation loss of a specific semiconductor module can be suppressed. Further, the power conversion efficiency of the power conversion device 1 can be improved.

[0045] In addition, a decrease in the thermal fatigue life of a specific semiconductor module can be suppressed. Thereby, the failure of the power conversion device 1 can be suppressed.

[0046] [2] Second Embodiment In the second embodiment, the connection position between the AC wiring 22 and the AC lead-out wiring 23 is set further away from the output terminal 13.

[0047] [2-1] Wiring Structure of Power Conversion Device 1 FIG. 4 is a perspective view showing the wiring structure of the power conversion device 1 according to the second embodiment. In FIG. 4, the semiconductor modules 10-1 to 10-4 are not shown, but their arrangements are the same as those in FIG. 2.

[0048] The center line C2 of the connection portion 23A of the AC lead-out wiring 23 is set farther from the center line C1 of the AC wiring 22. In other words, the AC lead-out wiring 23 is connected to the AC wiring 22 by being shifted farther from the center of the AC wiring 22 in the X direction from the output terminal 13.

[0049] The end portion of the AC wiring 22 on the side far from the output terminal 13 is referred to as an end region AR. In this embodiment, the length of the end region AR of the AC wiring 22 in the X direction is shortened. The end region AR of the AC wiring 22 is set to the minimum length necessary for fixing the AC wiring 22 and the protruding portion 21B of the connection wiring 21 with screws. The width (length in the Y direction) of the AC wiring 22 can be configured to be the same as that in the first embodiment.

[0050] The operation of the second embodiment is the same as that of the first embodiment.

[0051] [2-2] Effects of the Second Embodiment According to the second embodiment, while keeping the dimension in the depth direction the same as that of the first embodiment, the inductance difference can be made smaller than that of the first embodiment. Other effects are the same as those of the first embodiment.

[0052] [3] Third Embodiment In the third embodiment, the inductance difference between the semiconductor modules 10-1 to 10-4 is reduced by lengthening the path of the AC wiring 22.

[0053] [3-1] Wiring Structure of the Power Conversion Device 1 FIG. 5 is a perspective view showing the wiring structure of the power conversion device 1 according to the third embodiment. In FIG. 5, the semiconductor modules 10-1 to 10-4 are not shown, but their arrangements are the same as those in FIG. 2.

[0054] The AC wiring 22 is configured by connecting an extending portion 22A extending in the X direction, a protruding portion 22B protruding in the Z direction, and an extending portion 22C extending in the X direction in this order. The protruding portion 22B has an inverted U shape. The extending portion 22A of the AC wiring 22 is connected to the protruding portion 20B of the connection wiring 20 and fixed to the protruding portion 20B by a screw (not shown). The protruding portion 22B of the AC wiring 22 is arranged closer to the output terminal 13 than the connection portion 23A of the AC lead-out wiring 23.

[0055] The extending portion 22C of the AC wiring 22 is connected to the protruding portion 21B of the connection wiring 21 and fixed to the protruding portion 21B by a screw (not shown). Also, the extending portion 22C of the AC wiring 22 is connected to the connection portion 23A of the AC lead-out wiring 23.

[0056] The center line C2 of the connection portion 23A of the AC lead-out wiring 23 is set to be shifted to the side farther from the output terminal 13 from the center line C1 of the AC wiring 22.

[0057] Since the AC wiring 22 has the protruding portion 22B, the wiring path to the AC lead-out wiring 23 in the semiconductor modules 10-1 and 10-2 close to the output terminal 13 can be lengthened.

[0058] [3-2] Operation The operation of the power conversion device 1 configured as described above will be described.

[0059] Since the AC wiring 22 has the protruding portion 22B, the wiring paths of the semiconductor modules 10-1 and 10-2 become longer, so the inductance increases. As a result, the inductance difference between the semiconductor modules 10-1 and 10-2 and the semiconductor module 10-4 becomes smaller. Therefore, the inductance difference between the semiconductor modules 10-1 to 10-4 can be reduced, and the imbalance of the output current can be reduced.

[0060] [3-3] Effects of the Third Embodiment According to the third embodiment, the inductance difference can be made even smaller than that of the first embodiment while keeping the dimension in the depth direction the same as that of the first embodiment. Other effects are the same as those of the first embodiment.

[0061] [4] Fourth Embodiment In the fourth embodiment, the inductance difference between the semiconductor modules 10-1 to 10-4 is reduced by shortening the wiring path of the semiconductor module 10-4 farthest from the output terminal 13.

[0062] [4-1] Wiring Structure of the Power Conversion Device 1 FIG. 6 is a perspective view showing the wiring structure of the power conversion device 1 according to the fourth embodiment.

[0063] The AC lead-out wiring 23 is connected to the AC wiring 22 so as to cover the semiconductor module 10-4 that is the farthest from the output terminal 13. Also, the AC lead-out wiring 23 is connected to the AC wiring 22 so as to cover the boundary between the semiconductor modules 10-3 and 10-4 that are far from the output terminal 13. In other words, the connection portion 23A of the AC lead-out wiring 23 is arranged so as to cover the semiconductor module 10-4 that is the farthest from the output terminal 13. Also, the connection portion 23A of the AC lead-out wiring 23 is arranged so as to cover the boundary between the semiconductor modules 10-3 and 10-4 that are far from the output terminal 13.

[0064] In the configuration example of FIG. 6, the AC lead-out wiring 23 is configured to be connected to the AC wiring 22 at the end of the AC wiring 22. That is, the connection portion 23A of the AC lead-out wiring 23 is arranged at the end of the AC wiring 22.

[0065] Due to the need to ensure the area of the screw head for connecting the AC wiring 22, the connection portion 23A of the AC lead-out wiring 23 is configured to be drawn out in the Y direction as compared with the first embodiment. The length from the end of the AC wiring 22 to the end of the AC lead-out wiring 23 in the Y direction is referred to as L1. In the fourth embodiment, the length L1 becomes longer as compared with the first embodiment.

[0066] [4-2] Operation The operation of the power conversion device 1 configured as described above will be described.

[0067] By configuring as shown in FIG. 6, the wiring path of the semiconductor module 10-4 can be made shorter than that of the first embodiment. Thereby, the inductance from the semiconductor module 10-4 to the output terminal 13 can be reduced.

[0068] On the other hand, the wiring path of the semiconductor module 10-1 becomes longer than that of the first embodiment, but due to mutual inductance, there is almost no increase or decrease in inductance. That is, the current imbalance can be reduced due to the effect of suppressing the inductance difference of the four parallel semiconductor modules.

[0069] The fourth embodiment has a smaller inductance difference compared to the first embodiment and can suppress current imbalance. However, due to the need to secure the area of the screw head for connecting the AC wiring 22, the length L1 becomes longer than that of the first embodiment. As the length L1 increases, the distance between the AC wiring 22 and the AC lead-out wiring 23 becomes longer than that of the first embodiment, so the effect of reducing the inductance due to mutual induction becomes weaker. As a result, the inductance of the semiconductor module 10-1 can be increased, and the inductance difference between the four parallel semiconductor modules can be suppressed. Therefore, current imbalance can be reduced.

[0070] Even in the fourth embodiment, the same effects as those of the first embodiment can be obtained.

[0071] [5] Fifth Embodiment The fifth embodiment is a configuration example of three parallel semiconductor modules.

[0072] [5-1] Wiring Structure of Power Conversion Device 1 FIG. 7 is a perspective view showing the wiring structure of the power conversion device 1 according to the fifth embodiment. The power conversion device 1 includes three semiconductor modules 10-1 to 10-3. The semiconductor modules 10-1 to 10-3 are connected in parallel between the positive electrode terminal 14 and the negative electrode terminal 15. The semiconductor modules 10-1 to 10-3 are arranged side by side in the X direction.

[0073] The connection wiring 20 is configured by connecting an extending portion 20A extending in the X direction and a protruding portion 20B protruding in the Z direction. The protruding portion 20B has an inverted L shape. The extending portion 20A of the connection wiring 20 is connected to the AC terminal T3 of the semiconductor module 10-1 and is fixed to the AC terminal T3 by a screw (not shown).

[0074] The AC terminal T3 of the semiconductor module 10-2 and the AC terminal T3 of the semiconductor module 10-3 are connected by a connection wiring 21. Specifically, the connection wiring 21 is configured by connecting an extending portion 21A extending in the X direction, a protruding portion 21B protruding in the Z direction, and an extending portion 21C extending in the X direction in this order. The extending portion 21A of the connection wiring 21 is connected to the AC terminal T3 of the semiconductor module 10-2 and is fixed to the AC terminal T3 by a screw (not shown). The extending portion 21C of the connection wiring 21 is connected to the AC terminal T3 of the semiconductor module 10-3 and is fixed to the AC terminal T3 by a screw (not shown).

[0075] The AC wiring 22 connects the connection wiring 20 and the connection wiring 21. Specifically, one end of the AC wiring 22 is connected to the protruding portion 20B of the connection wiring 20 and is fixed to the protruding portion 20B by a screw (not shown), and the other end of the AC wiring 22 is connected to the protruding portion 21B of the connection wiring 21 and is fixed to the protruding portion 21B by a screw (not shown).

[0076] The AC lead-out wiring 23 connects the AC wiring 22 and the output terminal 13. The AC lead-out wiring 23 is configured to be drawn out from the AC wiring 22 in the Z direction and extend in the X direction. The AC lead-out wiring 23 includes a connection portion 23A connected to the AC wiring 22 and an extending portion 23B extending in the X direction from the connection portion 23A. The connection portion 23A is configured to include a curved portion drawn out in the Z direction.

[0077] The center line C2 of the connection portion 23A of the AC lead-out wiring 23 is set to be shifted to the side far from the output terminal 13 from the center line C1 of the AC wiring 22. In other words, the AC lead-out wiring 23 is connected to the AC wiring 22 by shifting it to the side far from the output terminal 13 from the center in the X direction of the AC wiring 22.

[0078] The longitudinal length (length in the X direction) of the AC wiring 22 is referred to as L2. The length (length in the X direction) of the connection portion 23A of the AC lead-out wiring 23 is referred to as L3. The length L3 of the connection portion 23A of the AC lead-out wiring 23 is set to be shorter than half of the longitudinal length L2 of the AC wiring 22.

[0079] [5-2] Operation The operation of the power conversion device 1 configured as described above will be described.

[0080] By configuring as shown in FIG. 7, the wiring path of the semiconductor module 10-1 can be lengthened. Thereby, the inductance from the semiconductor module 10-1 to the output terminal 13 can be increased. That is, from the action of suppressing the inductance difference of the three parallel semiconductor modules, the current imbalance can be reduced.

[0081] If the connection width (length L3) between the AC wiring 22 and the AC lead-out wiring 23 is large, the inductance from the semiconductor module 10-1 to the output terminal 13 will become small. For this reason, the inductance difference of the three parallel semiconductor modules will become large. However, in the present embodiment, the length L3 of the connection portion 23A is set to be shorter than half of the longitudinal length L2 of the AC wiring 22. Thereby, the wiring path of the semiconductor module 10-1 can be lengthened.

[0082] Also in the fifth embodiment, the same effects as in the first embodiment can be obtained.

[0083] [6] Sixth Embodiment In the sixth embodiment, by increasing the distance between the AC wiring 22 and the AC lead-out wiring 23, the inductance reduction effect due to mutual induction is reduced in the semiconductor module 10-1 closest to the output terminal 13 side.

[0084] [6-1] Wiring Structure of Power Conversion Device 1 The basic configuration of the power conversion device 1 is the same as that in FIG. 7 of the fifth embodiment. FIG. 8 is a front view showing the wiring structure of the power conversion device 1 according to the sixth embodiment. FIG. 8 is a front view seen from the Y direction of the wiring structure. The power conversion device 1 includes three semiconductor modules 10-1 to 10-3.

[0085] The thickness of the AC wiring 22 is referred to as T. The distance between the AC wiring 22 and the extending portion 23B of the AC lead-out wiring 23 is referred to as D. The distance D between the AC wiring 22 and the AC lead-out wiring 23 is set to be larger than the thickness T of the AC wiring 22.

[0086] [6-2] Operation The operation of the power conversion device 1 configured as described above will be described.

[0087] In this embodiment, by increasing the distance between the AC wiring 22 and the AC lead-out wiring 23, the inductance reduction effect due to mutual induction becomes smaller. As a result, the inductance from the semiconductor module 10-1 to the output terminal 13 can be increased.

[0088] On the other hand, regarding the inductance from the semiconductor module 10-3 to the output terminal 13, there is almost no mutual induction between the AC wiring 22 and the AC lead-out wiring 23, and it does not contribute to the increase or decrease of the inductance. That is, the current imbalance can be reduced from the effect of suppressing the inductance difference of the three parallel semiconductor modules.

[0089] In the sixth embodiment as well, the same effects as those in the first embodiment can be obtained.

[0090] The sixth embodiment is also applicable to four parallel semiconductor modules. Further, the sixth embodiment can also be applied to the first to fifth embodiments.

[0091] [7] Seventh Embodiment In the seventh embodiment, the AC wiring 22 and the extending portion 23B of the AC lead-out wiring 23 are configured to be perpendicular to each other. [7-1] Wiring Structure of Power Conversion Device 1 The basic configuration of the power conversion device 1 is the same as that shown in FIG. 7 of the fifth embodiment. FIG. 9 is a side view showing the wiring structure of the power conversion device 1 according to the seventh embodiment. FIG. 9 is a side view seen from the X direction of the wiring structure. The power conversion device 1 includes three semiconductor modules 10-1 to 10-3.

[0092] The extending portion 23B of the AC wiring 22 and the AC lead-out wiring 23 is configured to be perpendicular. In other words, the AC wiring 22 and the AC lead-out wiring 23 are configured such that their respective planar portions are perpendicular.

[0093] [7-2] Operation The operation of the power conversion device 1 configured as described above will be described.

[0094] In this embodiment, by arranging the respective planar portions of the AC wiring 22 and the AC lead-out wiring 23 at right angles, the inductance reduction effect due to mutual induction becomes small. Therefore, the inductance from the semiconductor module 10-1 to the output terminal 13 can be increased.

[0095] On the other hand, regarding the inductance from the semiconductor module 10-3 to the output terminal 13, there is almost no mutual induction between the AC wiring 22 and the AC lead-out wiring 23, and it does not contribute to the increase or decrease of the inductance. That is, the current imbalance can be reduced due to the effect of suppressing the inductance difference of the three parallel semiconductor modules.

[0096] In the seventh embodiment as well, the same effects as those of the first embodiment can be obtained.

[0097] The seventh embodiment is also applicable to four parallel semiconductor modules. Further, the seventh embodiment can also be applied to the first to sixth embodiments.

[0098] The power conversion device 1 according to each of the above embodiments is applicable to various devices and systems that handle AC power. In particular, the power conversion device 1 according to each of the above embodiments can be applied to a power conversion device for driving an elevator hoisting machine.

[0099] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and its equivalent scope.

Explanation of Reference Numerals

[0100] 1... Power conversion device, 10-1 to 10-4... Semiconductor modules, 11-1, 11-2... Switching elements, 12-1, 12-2... Diodes, 13... Output terminal, 14... Positive terminal, 15... Negative terminal, 16... Capacitor, 20, 21... Connection wiring, 22... AC wiring, 23... AC lead-out wiring, T1... Positive-side power supply terminal, T2... Negative-side power supply terminal, T3... AC terminal.

Claims

1. It has two switching elements connected in series, arranged side by side in a first direction, and a plurality of semiconductor modules connected in parallel, an AC wiring extending in the first direction and commonly connecting the AC terminals of the plurality of semiconductor modules, an AC lead-out wiring extending in the first direction and configured to lead the AC wiring to an output terminal, comprising: the AC lead-out wiring has a connection portion connected to the AC wiring and an extending portion arranged side by side with the AC wiring, the center of the connection portion of the AC lead-out wiring in the first direction is set on the side farther from the output terminal than the center of the plurality of semiconductor modules as a whole in the first direction power conversion device.

2. the AC wiring includes a protruding portion protruding upward within the wiring path from the semiconductor module closest to the output terminal to the AC lead-out wiring The power conversion device according to claim 1.

3. the connection portion of the AC lead-out wiring is arranged to straddle the boundary between two semiconductor modules on the side farther from the output terminal The power conversion device according to claim 1.

4. the length of the connection portion of the AC lead-out wiring in the first direction is set to be shorter than half of the length of the AC wiring in the first direction The power conversion device according to claim 1.

5. the distance between the AC wiring and the extending portion of the AC lead-out wiring is set to be greater than the thickness of the AC wiring The power conversion device according to claim 1.

6. the AC wiring and the extending portion of the AC lead-out wiring are configured to be perpendicular to each other The power conversion device according to claim 1.

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