JP2014049475A - Inverter device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inverter device capable of reducing a wiring inductance between an output electrode and an element group that are mounted on a substrate.SOLUTION: Input electrodes 30 and 40 and output electrodes 50, 60 and 70 respectively have terminal parts 31, 41, 51, 61 and 71 and bus bars 32, 42, 52, 62 and 72. The bus bars 32, 42, 52, 62 and 72 are arranged on a main circuit board 21 so that those longitudinal directions are parallel to a direction in which power elements of element groups G1-G6 are arranged. In the element groups G1, G4 and G5 configuring an upper arm switching element and element groups G2, G3 and G6 configuring a lower arm switching element, power elements 20 arranged at a position distant from the terminal parts 51, 61 and 71 of the output electrodes 50, 60 and 70 are arranged so as to approach each other, compared with power elements 20 close to the terminal parts 51, 61 and 71 of the output electrodes 50, 60 and 70.

Description

  The present invention relates to an inverter device in which upper and lower arm switching elements are each composed of a plurality of power elements connected in parallel, and the plurality of power elements and input / output electrodes are mounted on a substrate.

  In the semiconductor device (inverter) disclosed in Patent Document 1, as shown in FIG. 8, the upper and lower arm switching elements are each composed of a plurality of power elements (element groups) connected in parallel. Are arranged on the main circuit board, and positive and negative side input electrodes and U, V, and W phase output electrodes are arranged on the main circuit board.

Utility Model Registration No. 3173511

  As shown in FIG. 8, the semiconductor device described in Patent Document 1 is configured to switch the upper and lower arms of each phase between the bus bar 201a of the positive input electrode and the bus bar 202a of the negative input electrode on the main circuit board 200. The element groups G1 to G6 constituting the elements are arranged, and the bus bars 203, 204, and 205 of the output electrodes of each phase, the positive relay electrode 201b, and the negative electrode so as to be sandwiched between the upper arm and the lower arm of the element groups G1 to G6 The side relay electrode 202b is disposed, and the output electrode bus bars 203, 204, and 205 are configured to have a length facing each of the plurality of power elements constituting the element groups G1 to G6. In such an inverter device, the current flowing from each power element constituting the element group to the terminal portion of the output electrode tends to flow in the shortest path via the conductor pattern and the bus bar of the output electrode. In the power elements arranged at positions far from the output electrode terminal portions 206, 207, and 208 in G1 to G6), the current (path) i40 is slanted, and the magnetic flux canceling effect due to the mutual inductance at the time of switching is small.

  An object of the present invention is to provide an inverter device that can reduce wiring inductance between an output electrode mounted on a substrate and an element group.

  The invention according to claim 1 is an inverter device for converting electric power, wherein each of the upper arm switching element and the lower arm switching element has a plurality of power elements connected in parallel arranged in one direction on the substrate. Each element group is mounted on the substrate with a positive / negative input electrode interposed therebetween, and an output electrode is mounted so as to be sandwiched between the element groups. The input electrode and the output electrode Each includes a terminal portion and a bus bar, and the bus bar is disposed on the substrate such that a longitudinal direction thereof is parallel to a direction in which the power elements of the element group are arranged, and the switching element for the upper arm is provided. In the element group constituting and the element group constituting the lower arm switching element, disposed at a position far from the terminal portion of the output electrode. That power element, than the power element near the terminal portions of the output electrodes, and subject matter to be arranged so as to approach each other.

  According to the first aspect of the present invention, each of the input electrode and the output electrode includes a terminal portion and a bus bar, and the bus bar is a substrate whose longitudinal direction is parallel to the direction in which the power elements of the element group are arranged. The power element disposed at a position far from the terminal portion of the output electrode in the element group that is disposed above and constitutes the upper arm switching element and the element group that constitutes the lower arm switching element is the terminal of the output electrode. Compared with power elements close to each other, the power elements are arranged closer to each other, so that the power elements disposed far from the terminal portion of the output electrode and the power elements close to the terminal portion of the output electrode are equidistant. Compared to the arrangement, the wiring inductance between the output electrode mounted on the substrate and the element group can be reduced.

  According to a second aspect of the present invention, in the inverter device according to the first aspect of the present invention, the bus bar of the output electrode has a length that does not extend between the power elements that are arranged so that the longitudinal direction thereof is close to each other. It is good to be.

  According to a third aspect of the present invention, in the inverter device according to the first or second aspect, the bus bar of the input electrode has a portion facing the power element disposed so as to be close to each other, and the power element is connected to the power element. It is preferable that an approaching projecting portion is provided.

  According to the present invention, the wiring inductance between the output electrode mounted on the substrate and the element group can be reduced.

The disassembled perspective view which shows the inverter apparatus of embodiment. The front view of an inverter apparatus. The circuit block diagram of an inverter apparatus. The top view which shows a main circuit board. The partial enlarged plan view of the main circuit board. The wave form diagram which shows the electric current which flows into an output electrode. The partial schematic top view of the main circuit board in an inverter apparatus. The top view for demonstrating a subject.

Hereinafter, an embodiment in which the present invention is embodied in an inverter device mounted on a vehicle will be described with reference to FIGS.
In the drawings, the horizontal plane is defined by the orthogonal X and Y directions, and the vertical direction is defined by the Z direction.

  As shown in FIGS. 1 and 2, the main circuit board 21 is disposed on the upper surface of a heat sink HS having a thin flat shape as an overall configuration. The capacitor substrate 100 is disposed above the main circuit board 21 so as to face the main circuit board 21. Further, the control circuit board 110 is disposed above the capacitor board 100 via the auxiliary bracket body 121.

  A plurality of power elements 20, a positive side input electrode 30, a negative side input electrode 40, a U phase output electrode 50, a V phase output electrode 60, a W phase output electrode 70 and the like are mounted on the main circuit board 21. A plurality of capacitors 101 are mounted on the capacitor substrate 100. Various electronic components 111 are mounted on the control circuit board 110.

  As shown in FIG. 3, the inverter device 10 of the present embodiment is a three-phase inverter that supplies three-phase AC power to a motor, and converts DC power supplied from a battery into AC power. In FIG. 3, the U-phase includes an upper arm switching element Q1 and a lower arm switching element Q2, and both switching elements Q1 and Q2 are connected in series. Further, for the V phase, an upper arm switching element Q4 and a lower arm switching element Q3 are provided, and both the switching elements Q3 and Q4 are connected in series. Further, for the W phase, an upper arm switching element Q5 and a lower arm switching element Q6 are provided, and both the switching elements Q5 and Q6 are connected in series. Diodes D1, D2, D3, D4, D5, and D6 are connected in parallel to the switching elements Q1 to Q6, respectively. A MOSFET is used for each switching element. The switching elements Q1 to Q6 and the diodes D1 to D6 are mounted on the main circuit board 21.

  As shown in FIGS. 1 and 4, the upper arm switching element Q <b> 1 includes a plurality (12 in this embodiment) of power elements 20 connected in parallel in one direction (Y direction) on the main circuit board 21. The first element group G1 is arranged in a line. Specifically, the power element 20 is a switching element in which diodes are connected in parallel, and the power element 20 is mounted on the main circuit board 21. Similarly, the lower arm switching element Q2 includes a plurality of (in the present embodiment, 12) power elements 20 connected in parallel arranged in a line on the main circuit board 21 in one direction (Y direction). It is configured as two element groups G2. The lower arm switching element Q3 includes a third element group G3 in which a plurality of (in this embodiment, 12) power elements 20 connected in parallel are arranged in a line on the main circuit board 21 in one direction (Y direction). It is configured as. The upper arm switching element Q4 includes a fourth element group G4 in which a plurality of (in this embodiment, 12) power elements 20 connected in parallel are arranged in a line on the main circuit board 21 in one direction (Y direction). It is configured as. The upper arm switching element Q5 includes a fifth element group G5 in which a plurality of (in this embodiment, 12) power elements 20 connected in parallel are arranged in a line on the main circuit board 21 in one direction (Y direction). It is configured as. The lower arm switching element Q6 includes a sixth element group G6 in which a plurality of (in this embodiment, 12) power elements 20 connected in parallel are arranged in a line on the main circuit board 21 in one direction (Y direction). It is configured as.

  In this way, the upper arm switching elements Q1, Q4, and Q5 and the lower arm switching elements Q2, Q3, and Q6 are configured so that the plurality of power elements 20 connected in parallel are arranged in one direction on the main circuit board 21 ( The element groups G1 to G6 are arranged in a line in the Y direction. As shown in FIGS. 1 and 4, a plurality of power elements 20 are mounted on the main circuit board 21, but are shown equivalently in FIG. 3 for the sake of simplicity.

  In FIG. 3, the connection point between the U-phase upper arm switching element Q <b> 1 and the lower arm switching element Q <b> 2 is connected to the U-phase output electrode 50. A connection point between the V-phase upper arm switching element Q 4 and the lower arm switching element Q 3 is connected to the V-phase output electrode 60. A connection point between W-phase upper arm switching element Q5 and lower arm switching element Q6 is connected to W-phase output electrode. The U-phase output electrode 50, the V-phase output electrode 60, and the W-phase output electrode 70 are connected to an in-vehicle travel motor (not shown) as an output device.

  In the main circuit board 21 of FIG. 4, the drain of the switching element Q1 (first element group G1) is electrically connected to the positive input electrode 30 through the conductor pattern P10 (see FIG. 5). The drains of the switching elements Q4 and Q5 (fourth element group G4, fifth element group G5) are electrically connected to the positive relay electrode 24 through the conductor pattern, and the positive relay electrode 24 is connected to the conductor pattern. It is electrically connected to the positive input electrode 30 through P1 (see FIG. 4). The sources of the switching elements Q2 and Q3 (second element group G2, third element group G3) are electrically connected to the negative side relay electrode 23 through the conductor pattern, and the negative side relay electrode 23 is electrically connected to the conductor pattern P2 ( 4) and is electrically connected to the negative input electrode 40. The source of the switching element Q6 (sixth element group G6) is electrically connected to the negative input electrode 40 through the conductor pattern.

  In FIG. 3, a plurality of capacitors 101 are connected in parallel between the positive electrode side input electrode 30 and the negative electrode side input electrode 40. A plurality of these capacitors 101 are mounted on the capacitor substrate 100.

  1 and 4, the element groups G1 to G6 are mounted on the main circuit board 21 with the positive and negative input electrodes 30 and 40 interposed therebetween, and the output electrodes 50 and 60 are sandwiched between the element groups G1 to G6. , 70 are installed.

  Specifically, the first element group G1, the second element group G2, the third element group G3, the fourth element group G4, the fifth element group G5, the sixth element in order from left to right in the X direction. Element group G6 is arranged. Further, the positive electrode side input electrode 30 is disposed on the leftmost side in the X direction, and the negative electrode side input electrode 40 is disposed on the rightmost side in the X direction. A U-phase output electrode 50 is disposed between the first element group G1 and the second element group G2 in the X direction. A V-phase output electrode 60 is disposed between the third element group G3 and the fourth element group G4 in the X direction. A W-phase output electrode 70 is disposed between the fifth element group G5 and the sixth element group G6 in the X direction.

  Further, the relay electrodes 23 and 24 are mounted on the main circuit board 21 so as to be sandwiched between the element groups G2, G3, G4, and G5. Specifically, the negative electrode side relay electrode 23 is disposed between the second element group G2 and the third element group G3 in the X direction, and as described above, the negative electrode side relay electrode 23 is negatively connected by the conductor pattern P2. The side input electrode 40 is electrically connected. Further, the positive relay electrode 24 is arranged between the fourth element group G4 and the fifth element group G5 in the X direction. As described above, the positive relay electrode 24 is connected to the positive electrode side by the conductor pattern P1. The input electrode 30 is electrically connected.

  In FIG. 3, the positive electrode terminal and the negative electrode terminal of the in-vehicle battery Bc are connected to the positive electrode side input electrode 30 and the negative electrode side input electrode 40 of the inverter device 10 via a capacitor 101. The gates of the switching elements Q1 to Q6 are connected to an electronic component 111 that constitutes a control circuit via a flat cable CF. The electronic component 111 constituting the control circuit is mounted on the control circuit board 110 (see FIGS. 1 and 2). Then, the switching elements Q1 to Q6 are subjected to switching control by the control circuit of the control circuit board 110 so as to supply electric power to the vehicle-mounted traveling motor.

  As shown in FIGS. 1 and 4, positive and negative input electrodes 30 and 40 made of aluminum and output electrodes 50, 60 and 70 of each phase are respectively connected to terminal portions 31, 41, 51, 61 and 71 and bus bars (band plates). Part) 32, 42, 52, 62, 72. The terminal portions 31, 41, 51, 61, 71 are formed in a substantially rod shape. Bus bars 32, 42, 52, 62, 72 are arranged on the conductor pattern of main circuit board 21. FIG. 5 shows a state in which the bus bar 32 of the positive input electrode 30 is mounted on the conductor pattern P10 and each power element 20 constituting the first element group G1 is mounted on the conductor pattern P10. The same applies to the negative side input electrode 40. In FIG. 5, the bus bar 52 of the U-phase output electrode 50 is mounted on the conductor pattern P11, and the power elements 20 constituting the second element group G2 are mounted on the conductor pattern P11. Show. The same applies to the output electrodes 60 and 70 of the other phases.

  The bus bars 32, 42, 52, 62, 72 are formed in an elongated rectangular plate shape (band shape), and are electrically connected in surface contact with the conductor pattern. In the input electrodes 30, 40 and the output electrodes 50, 60, 70, round bar-shaped terminal portions 31, 41, 51, 61, 71 stand at the center in the length direction of the bus bars 32, 42, 52, 62, 72. It is installed.

  The bus bars 32, 42, 52, 62, 72 are arranged on the main circuit board 21 so that the longitudinal direction thereof is parallel to the direction (Y direction) in which the power elements 20 of the element groups G1 to G6 are arranged.

  As shown in FIG. 4, with respect to the element group G1 constituting the upper arm switching element and the element group G2 constituting the lower arm switching element, the power element 20 ( The three power elements are disposed closer to each other than the power elements 20 (six power elements) close to the terminal portion 51 of the output electrode 50. Similarly, for the element group G4 that constitutes the upper arm switching element and the element group G3 that constitutes the lower arm switching element, the power elements 20 (three each of which are arranged at positions far from the terminal portion 61 of the output electrode 60). Are arranged closer to each other than the power elements 20 (six power elements) close to the terminal portion 61 of the output electrode 60. Further, for the element group G5 constituting the upper arm switching element and the element group G6 constituting the lower arm switching element, the power element 20 (three power elements each) arranged at a position far from the terminal portion 71 of the output electrode 70. Are arranged closer to each other than the power elements 20 (six power elements) close to the terminal portion 71 of the output electrode 70.

  The bus bar 52 of the output electrode 50 has a length that does not extend between the power elements 20 that are arranged so that their longitudinal directions are close to each other. Specifically, the bus bar 52 of the output electrode 50 is shortened so that the length L1 in the longitudinal direction does not extend to the location where the power elements 20 are arranged so as to approach each other. That is, the bus bar 52 is disposed only in a portion close to the terminal portion 51 of the output electrode 50 in the power elements of the element group.

  Similarly, the bus bar 62 of the output electrode 60 has a length that does not extend between the power elements 20 that are arranged so that their longitudinal directions are close to each other. Specifically, the bus bar 62 of the output electrode 60 is shortened so that the length L2 in the longitudinal direction does not extend to the place where the power elements 20 arranged so as to approach each other (element group). The bus bar 62 is disposed only in a portion close to the terminal portion 61 of the output electrode 60 among the power elements. Further, the bus bar 72 of the output electrode 70 has a length that does not extend between the power elements 20 arranged so that the longitudinal direction thereof is close to each other. Specifically, the bus bar 72 of the output electrode 70 is shortened so that the length L3 in the longitudinal direction does not extend to the location where the power elements 20 are arranged so as to approach each other (element group). The bus bar 72 is disposed only in a portion close to the terminal portion 71 of the output electrode 70 of the power elements.

  The bus bar 32 of the input electrode 30 is provided with a protruding portion 32b that approaches the power element 20 at a portion that faces the power element 20 that is arranged so as to approach each other. That is, with respect to the bus bar 32 of the input electrode 30, the place where the power element 20 is placed so as to be close to each other is protruded from the main body part 32 a by the distance d 11 so that the protruding part 32 b is close to the power element 20. Yes.

  Similarly, the bus bar 42 of the input electrode 40 is provided with a protruding portion 42b that approaches the power element 20 at a portion facing the power element 20 that is arranged so as to approach each other. In other words, with respect to the bus bar 42 of the input electrode 40, the power element 20 disposed so as to be close to each other is protruded from the main body 42 a by the distance d 12 so that the protruding part 42 b approaches the power element 20. Yes.

  Moreover, the negative electrode side relay electrode 23 is arrange | positioned on the main circuit board 21 so that the longitudinal direction may become parallel to the direction (Y direction) in which the power elements 20 of the element groups G1-G6 are arranged. The positive relay electrode 24 is arranged on the main circuit board 21 so that the longitudinal direction thereof is parallel to the direction in which the power elements 20 of the element groups G1 to G6 are arranged (Y direction).

  As for the location where the power elements 20 are arranged so as to be close to each other with respect to the negative electrode side relay electrode 23, the projecting portion 23b is a distance from one side surface of the main body portion 23a toward the second element group G2 (power element 20). Projection is provided so as to approach the power element 20 by d13. Further, the projecting portion 23c is projected from the other side surface of the main body portion 23a toward the third element group G3 (power element 20) so as to approach the power element 20 by a distance d14. Similarly, with respect to the positive relay electrode 24, the protruding portion 24b is directed from the one side surface of the main body 24a toward the fourth element group G4 (power element 20) with respect to the arrangement location of the power elements 20 arranged so as to approach each other. And projecting so as to approach the power element 20 by a distance d15. Further, the projecting portion 24c is projected from the other side surface of the main body portion 24a toward the fifth element group G5 (power element 20) so as to approach the power element 20 by a distance d16.

  As shown in FIGS. 1 and 2, the capacitor substrate 100 is mounted on the upper surfaces of the bus bars 32 and 42 in the positive and negative input electrodes 30 and 40. The positive electrode side input electrode 30 and the negative electrode side input electrode 40 are electrically connected to the capacitor substrate 100 via bus bars 32 and 42. Further, in the rod-like terminal portions 31 and 41 of the positive and negative input electrodes 30 and 40, control circuit board support portions 33 and 43 project from the upper peripheral surface.

  The capacitor substrate 100 is penetrated by rod-shaped terminal portions 51, 61, 71 of the U-phase output electrode 50, the V-phase output electrode 60, and the W-phase output electrode 70. On the main circuit board 21, the auxiliary bracket body 121 is fixed to the main circuit board 21 by a pair of legs 122, and the auxiliary bracket body 121 has the control circuit board support 33 for the positive and negative input electrodes 30, 40, 43 is supported. Further, the terminal portions 51, 61, 71 of the U-phase output electrode 50, the V-phase output electrode 60, and the W-phase output electrode 70 pass through the auxiliary bracket main body 121. A control circuit board 110 is supported on the auxiliary bracket body 121, and terminal portions 51, 61, 71 of the U-phase output electrode 50, the V-phase output electrode 60, and the W-phase output electrode 70 are provided on the control circuit board 110. It penetrates. The control circuit board support portions 33 and 43 are electrically connected to the control circuit board 110 through the conductive collar 123. The control circuit board 110 is provided with a control circuit side connector portion 112, and the main circuit board 21 and the control circuit board 110 are electrically connected by a flat cable CF as a connecting member.

Next, the operation of the inverter device 10 configured as described above will be described.
The direct current from the in-vehicle battery Bc is supplied to the main circuit board 21 via the capacitor board 100. The upper arm switching elements Q1, Q4, and Q5 (power elements 20 of the first, fourth, and fifth element groups G1, G4, and G5) and the lower arm switching elements Q2, Q3, and Q6 (second, The U-phase output electrode 50, the V-phase output electrode 60, and the W-phase output electrode are respectively controlled by turning on / off the power elements 20) of the third and sixth element groups G2, G3, and G6 at predetermined timings. From 70, an alternating current is supplied to the vehicle-mounted traveling motor.

  When the positive input electrode 30 and the negative input electrode 40 generate heat, the heat is transmitted from the bus bars 32 and 42 to the heat sink HS through the main circuit board 21 and is radiated. Further, the heat accompanying the switching operation in the switching elements Q1 to Q6 (element groups G1 to G6) is transmitted to the heat sink HS through the main circuit board 21 and radiated.

Here, reference will be made to the current flow in the main circuit board 21 accompanying the on / off control of the switching elements Q1 to Q6 (element groups G1 to G6).
The DC power supplied from the in-vehicle battery Bc is converted into AC power by the inverter device 10 and output to the external load from the output electrodes 50, 60 and 70.

  For example, when the upper arm switching element is switched from on to off, as shown in FIG. 3, the current i10 flowing through the upper arm switching element gradually decreases, and the current i20 flowing through the lower arm switching element is reduced. Increase gradually. These currents i10 and i20 are shown by the waveforms in FIG. A current flows similarly in the V phase and the W phase.

  At this time, as shown in FIG. 4, the output electrodes 50, 60 in the element groups G1, G4, G5 constituting the upper arm switching element and the element groups G2, G3, G6 constituting the lower arm switching element. , 70 so that the power elements 20 arranged at positions far from the terminal portions 51, 61, 71 are closer to each other than the power elements 20 close to the terminal portions 51, 61, 71 of the output electrodes 50, 60, 70. Arranged. Therefore, a current flows from the element group to the output electrode through a conductor pattern formed on the main circuit board 21, and the output electrodes 50, 60, 70 mounted on the main circuit board 21 at that time and the element groups G1 to G1. Wiring inductance with G6 can be reduced.

This will be described in more detail with reference to FIG.
The solid line in FIG. 7 is the present embodiment, and corresponds to FIG. The two-dot chain line in FIG. 7 is a comparative example and corresponds to FIG.

  As shown in FIG. 4, the power elements (MOS transistors) 20 at the ends of the element groups G1 to G6 are moved toward the center, and the bus bars 52, 62 of the output electrodes 50, 60, 70 at the positions where the shifted power elements 20 are arranged. 72, lengths L1, L2, and L3 are shortened. The bus bars 32 and 42 and the main body portions 32a, 42a, 23a, and 24a of the relay electrodes 23 and 24 are provided with projecting portions 32b, 42b, 23b, 23c, 24b, and 24c, and the bus bar and the main body portions of the relay electrodes are provided in the element group. Moved closer. With such a configuration, it is possible to increase the magnetic flux canceling effect due to the mutual inductance. Therefore, inductance can be reduced.

  Specifically, in the comparative example shown in FIG. 8, the current tends to flow at the shortest distance. Therefore, the current path of the current i40 (see FIG. 7) flowing from the power element (MOS transistor) 20 provided on the end side of the element group constituting the upper arm switching element to the terminal portion of the output electrode, and the lower arm switching element The current path of the current i40 (see FIG. 7) flowing from the power element provided on the end side of the element group constituting the output electrode to the terminal portion of the output electrode includes a relatively large portion that is not parallel. As a result, the magnetic flux canceling effect due to the mutual inductance is reduced.

  On the other hand, in the present embodiment, the power element (MOS transistor) 20 disposed on the end side of the element group of the upper arm switching element far from the terminal portion of the output electrode and the end side of the element group of the lower arm switching element. The power elements arranged on the upper arm switching element are brought close to each other, whereby the current path of the current i30 (see FIG. 7) flowing from the power element (MOS transistor) 20 on the end side of the upper arm switching element to the terminal portion of the output electrode The current path of the current i30 (see FIG. 7) flowing from the power element (MOS transistor) 20 on the end side of the lower arm switching element to the terminal portion of the output electrode is parallel in many parts. As a result, the magnetic flux canceling effect due to the mutual inductance is increased.

  In this way, by reducing the wiring inductance, the switching surge voltage can be reduced even when the power element is switched at the same switching speed as in the prior art. Therefore, an element with a lower withstand voltage and a lower price can be employed. Alternatively, even if the switching speed is further increased, the switching surge voltage is equivalent to that of the conventional one, so that the switching loss can be reduced, and the cooling system can be made small and inexpensive.

According to the above embodiment, the following effects can be obtained.
(1) Terminal portions 51 of the output electrodes 50, 60, 70 in the element groups G1, G4, G5 constituting the upper arm switching element and the element groups G2, G3, G6 constituting the lower arm switching element, The power elements 20 arranged at positions far from 61 and 71 are arranged closer to each other than the power elements 20 close to the terminal portions 51, 61 and 71 of the output electrodes 50, 60 and 70. Thereby, the power element 20 disposed at a position far from the terminal portions 51, 61, 71 of the output electrodes 50, 60, 70 and the power element 20 close to the terminal portions 51, 61, 71 of the output electrodes 50, 60, 70. Can be reduced compared to the case where they are arranged at equal distances, the wiring inductance between the output electrodes 50, 60, 70 mounted on the main circuit board 21 and the element groups G1 to G6 can be reduced.

  (2) The bus bars 52, 62, 72 of the output electrodes 50, 60, 70 have a length that does not extend between the power elements 20 arranged so that their longitudinal directions are close to each other. Thereby, the power elements 20 arranged at positions far from the terminal portions 51, 61, 71 of the output electrodes 50, 60, 70 can be easily arranged so as to approach each other.

  (3) The bus bars 32 and 42 of the input electrodes 30 and 40 are provided with projecting portions 32b and 42b approaching the power element 20 at portions facing the power element 20 disposed so as to approach each other. Yes. Thereby, regarding the relationship between the input electrodes 30 and 40 and the element groups G1 and G6, the wiring distance (current) between the power elements 20 arranged at positions far from the terminal portions 51, 61, and 71 of the output electrodes 50, 60, and 70. Path) and the wiring distance (current path) of the power element 20 close to the terminal portions 51, 61, 71 of the output electrodes 50, 60, 70 can be equalized.

The embodiment is not limited to the above, and may be embodied as follows, for example.
-Although MOSFET was used as a switching element, you may use IGBT.
The output electrode bus bars 52, 62, 72 are shortened so as not to extend to the locations where the power elements 20 are arranged so as to be close to each other, but instead, the power bars are arranged so as to be close to each other. The element 20 may be thinned and extended at an arrangement place.

  The output electrodes 50, 60, 70 have the terminal portions 51, 61, 71 arranged at the center in the longitudinal direction of the bus bars 52, 62, 72. However, the present invention is not limited to this, and the terminal portions 51, 61, 71 are You may arrange | position in parts other than the center part of the longitudinal direction of bus-bar 52,62,72. In short, in the element group constituting the upper arm switching element and the element group constituting the lower arm switching element, the power element disposed at a position far from the terminal part of the output electrode is used as the terminal part of the output electrode. What is necessary is just to arrange | position so that it may mutually approach compared with a near power element.

  DESCRIPTION OF SYMBOLS 10 ... Inverter apparatus, 20 ... Power element, 21 ... Main circuit board, 30 ... Positive electrode side input electrode, 31 ... Terminal part, 32 ... Bus bar, 32b ... Projection part, 40 ... Negative electrode side input electrode, 41 ... Terminal part, 42 ... Bus bar, 42b ... Projecting portion, 50 ... U-phase output electrode, 51 ... Terminal portion, 52 ... Bus bar, 60 ... V-phase output electrode, 61 ... Terminal portion, 62 ... Bus bar, 70 ... W-phase output electrode, 71 ... Terminal part, 72 ... Bus bar, Q1, Q4, Q5 ... Upper arm switching element, Q2, Q3, Q6 ... Lower arm switching element, G1 ... First element group, G2 ... Second element group, G3 ... 3rd element group, G4 ... 4th element group, G5 ... 5th element group, G6 ... 6th element group.

Claims (3)

An inverter device for converting electric power,
Each of the upper arm switching element and the lower arm switching element is configured as an element group in which a plurality of power elements connected in parallel are arranged in a line on one direction on the substrate, and the positive and negative input electrodes are sandwiched on the substrate. And each element group is mounted and an output electrode is mounted so as to be sandwiched between the element groups,
The input electrode and the output electrode each include a terminal portion and a bus bar,
The bus bar is disposed on the substrate such that a longitudinal direction thereof is parallel to a direction in which the power elements of the element group are arranged,
In the element group constituting the upper arm switching element, and in the element group constituting the lower arm switching element, a power element disposed at a position far from the terminal portion of the output electrode is the output electrode. An inverter device, which is arranged so as to be closer to each other than a power element close to a terminal portion.   2. The inverter device according to claim 1, wherein the bus bar of the output electrode has a length that does not extend between the power elements arranged so as to approach each other.   3. A protruding portion that approaches the power element is provided on a portion of the bus bar of the input electrode that faces the power element that is disposed so as to be close to each other. The described inverter device.