JP5516187B2 - Power converter - Google Patents

Description

  The present invention relates to a power converter used together with an electric motor (rotary electric machine) or the like.

  Patent Document 1 discloses a multiphase inverter (power converter) disposed in a case of an electric motor as a conventional technique. The multi-phase inverter has a plurality of single-phase inverter circuits connected in parallel, and the single-phase inverter circuit is connected to each coil of the electric motor. The single-phase inverter circuit includes an upper arm side switching element (semiconductor element) and a lower arm side switching element (semiconductor element) connected in series. The switching element on the upper arm side is a switching element connected to the positive electrode side of the DC power supply, and the switching element on the lower arm side is a switching element connected to the negative electrode side of the DC power supply.

JP 2007-116840 A

  However, in the above prior art, a cooler is disposed only on the lower side of the semiconductor element, and there is no cooler or cooling member on the upper side of the semiconductor element (FIG. 19 of Patent Document 1). A bonding wire connected to the bus bar is disposed on the upper side of the semiconductor element. In this configuration, since the heat transfer path is only on the lower side (one side) of the semiconductor element and not on the upper side (the other side), the heat transfer path is narrow and the cooling efficiency of the semiconductor element is low. is there.

  The present invention has been made paying attention to such a conventional problem, and an object thereof is to improve the cooling efficiency of a semiconductor element of a power converter.

  A power converter according to an aspect of the present invention is mounted on a case in which a rotating electrical machine is accommodated via an insulating member. The power converter includes a plurality of first electrodes, a first semiconductor element for switching bonded to each first electrode, a second semiconductor element for return current bonded to each first electrode, And a second electrode joined to the first semiconductor element and the second semiconductor element. At least one semiconductor element on one first electrode is opposed to at least one semiconductor element on another adjacent first electrode, and straddles the first and second semiconductor elements of both first electrodes. The second electrode is disposed. The second electrode has a portion extending toward the case between the first electrodes, and is joined to the inner wall of the case via the insulating member.

  ADVANTAGE OF THE INVENTION According to this invention, the cooling efficiency of the semiconductor element of a power converter can be improved by expanding the heat-transfer path | route from a semiconductor element.

(A) It is an end elevation of the power converter concerning a first embodiment. (B) It is sectional drawing along the sequence direction of the semiconductor element of the power converter which concerns on 1st embodiment. It is a circuit diagram which shows an example of the circuit structure of a power converter. (A) It is an end view of the power converter from which the arrangement | sequence of a semiconductor element differs from 1st embodiment. (B) It is sectional drawing along the arrangement direction of the semiconductor element of the power converter in which the arrangement | sequence of a semiconductor element differs from 1st embodiment. (A) It is an end elevation of the power converter concerning a second embodiment. (B) It is sectional drawing along the sequence direction of the semiconductor element of the power converter which concerns on 2nd embodiment. It is sectional drawing of the rotating shaft direction which shows the rotary electric machine and power converter which concern on 3rd embodiment. (A) It is an end elevation of the power converter concerning a third embodiment. (B) It is sectional drawing along the sequence direction of the semiconductor element of the power converter which concerns on 3rd embodiment. It is sectional drawing of the rotating shaft direction which shows the rotary electric machine and power converter which concern on 4th embodiment. (A) It is an end elevation of the power converter concerning a 4th embodiment. (B) It is sectional drawing along the sequence direction of the semiconductor element of the power converter which concerns on 4th embodiment. It is sectional drawing of the rotating shaft direction which shows an example of the rotary electric machine and power converter which concern on 5th embodiment. It is sectional drawing of the rotating shaft direction which shows the other example of the rotary electric machine and power converter which concern on 5th embodiment. (A) It is an end view of the power converter concerning a 6th embodiment. (B) It is sectional drawing along the sequence direction of the semiconductor element of the power converter which concerns on 6th embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described in more detail with reference to the drawings.

<First embodiment>
Fig.1 (a) and FIG.1 (b) each show the end elevation and sectional drawing of the power converter 100 which concern on 1st embodiment. In the present embodiment, the power converter 100 is disposed in the case 10 together with the electric motor (rotating electric machine) 50 and supplies power to the electric motor 50. The power converter 100 is an inverter as shown in FIG. 2, but is not limited to this.

  In the first embodiment, the power converter 100 includes a plurality of flat plate-like power modules 18 arranged in parallel to the surface of the case 10. Here, the power module 18 is shown as a component corresponding to a single-phase inverter circuit. The plurality of power modules 18 are arranged in parallel to each other.

  The power module 18 includes an upper arm side switching semiconductor element 4 and a lower arm side switching semiconductor element 6 which are connected in series. Further, the power module 18 includes a reflux current semiconductor element 5 on the upper arm side and a reflux current semiconductor element 7 on the lower arm side. The switching semiconductor element 4 (first semiconductor element) on the upper arm side is connected in parallel to the reflux current semiconductor element 5 (second semiconductor element) on the upper arm side. The lower arm switching semiconductor element 6 (third semiconductor element) is connected in parallel to the lower arm reflux current semiconductor element 7 (fourth semiconductor element). For example, the semiconductor element for switching is a transistor, and the semiconductor element for reflux current is a diode. Each flat semiconductor element (semiconductor element chip) and each substantially flat electrode are arranged in parallel to the mounting surface of the case.

  The switching semiconductor element 4 and the reflux current semiconductor element 5 on the upper arm side are connected to the positive electrode side of the DC power supply 30. The lower-arm switching semiconductor element 6 and the reflux current semiconductor element 7 are connected to the negative electrode side of the DC power supply 30.

  The switching semiconductor element 4 on the upper arm side and the switching semiconductor element 6 on the lower arm side are bonded to one surface of the first electrode 1 directly or via the conductive bonding member 8. The upper-arm-side return current semiconductor element 5 and the lower-arm-side return current semiconductor element 7 are also bonded to one surface of the first electrode 1 directly or via the conductive bonding member 8.

  The second electrode 2 on the upper arm side is bonded to the first and second semiconductor elements 4 and 5 on the upper arm side directly or through the conductive bonding member 8. The third electrode 3 on the lower arm side is joined to the second and fourth semiconductor elements 6 and 7 on the lower arm side directly or through the conductive joining member 8. The second electrode 2 on the upper arm side and the third electrode 3 on the lower arm side are connected via the insulating member 9 to the mounting surface of the inner wall of the case 10 to which the motor 50 and the power converter 100 are fixed.

  The case 10 may include a heat sink or a water jacket as a radiator. In the first embodiment, the case 10 has a heat sink 10a, and the power converter 100 is attached to a location corresponding to the heat sink 10a of the case 10.

  On the first electrode 1, an upper arm side semiconductor element group (first semiconductor element 4 and second semiconductor element 5) and a lower arm side semiconductor element group (third semiconductor element 6 and fourth semiconductor). Elements 7) are arranged in the arrangement direction. The upper arm side semiconductor element group and the lower arm side semiconductor element group on one first electrode 1 are respectively an upper arm side semiconductor element group and a lower arm side semiconductor element group on another adjacent first electrode 1. And are arranged in plane symmetry.

  The upper arm side semiconductor elements 4a and 4b (5a and 5b) respectively disposed on the first electrodes 1a and 1b adjacent to each other face each other with the leg portion 2a of the second electrode 2 interposed therebetween. The second electrode 2 has a T-shaped cross-sectional shape and is disposed so as to straddle the semiconductor elements 4a, 4b (5a, 5b) on the upper arm side adjacent to each other. That is, the top plate portion 2b of the second electrode 2 is disposed on the semiconductor element 4a (5a) and the semiconductor element 4b (5b). The insulating member 9, the first electrode 1, the conductive bonding member 8, the semiconductor element 4, and the top plate portion 2b of the second electrode 2 are stacked in a direction perpendicular to the case surface (mounting surface) on which the power module is mounted. Has been.

  The lower arm side semiconductor elements 6a and 6c (7a and 7c) respectively disposed on the adjacent first electrodes 1a and 1c oppose each other with the leg 3a of the third electrode 3 interposed therebetween. The third electrode 3 has a T-shaped cross-sectional shape and is disposed so as to straddle the adjacent semiconductor elements 6a and 6c (7a and 7c) on the lower arm side. That is, the top plate portion 3b of the third electrode 3 is disposed on the semiconductor element 6a (7a) and the semiconductor element 6c (7c). The insulating member 9, the first electrode 1, the conductive bonding member 8, the semiconductor element 6, and the top plate portion 3b of the third electrode 3 are stacked in a direction perpendicular to the case surface (mounting surface) on which the power module is mounted. Has been.

  The pair of switching semiconductor elements 4 on the upper arm side facing each other with the leg part 2a of the second electrode 2 interposed therebetween, and the switching semiconductor element 6 on the lower arm side facing each other with the leg part 3a of the third electrode 3 interposed therebetween. Are alternately arranged in the arrangement direction. Similarly, the pair of reflux current semiconductor elements 5 on the upper arm side facing each other across the leg 2a of the second electrode 2 and the reflux on the lower arm side facing each other across the leg 3a of the third electrode 3 The pairs of current semiconductor elements 7 are alternately arranged in the arrangement direction.

  The leg 2a of the second electrode 2 extends toward the inner wall of the case 10 between the first electrodes 1a and 1b, and is in contact with or joined to the case 10 via the insulating member 9. The leg portion 3 a of the third electrode 3 extends toward the inner wall of the case 10 between the first electrodes 1 a and 1 c and is in contact with or joined to the case 10 via the insulating member 9.

  On one side (case side) of the semiconductor elements 4a, 4b (5a, 5b) on the upper arm side, the first electrodes 1a, 1b serve as a heat transfer path, and the heat of the semiconductor elements 4a, 4b (5a, 5b) is transmitted. Transmit to case 10. On the other side (opposite side of the case) of the semiconductor elements 4a, 4b (5a, 5b) on the upper arm side, the top plate portion 2b of the second electrode 2 becomes a heat transfer path, and the semiconductor elements 4a, 4b (5a, The heat of 5b) is transmitted to the case 10 through the leg 2a. Therefore, heat can be transferred to the case 10 from both sides of the semiconductor elements 4a and 4b (5a and 5b).

  Further, the first electrodes 1a and 1c serve as a heat transfer path, and the semiconductor elements 6a and 6c (7a and 7c) are connected from one side (case side) of the semiconductor elements 6a and 6c (7a and 7c) on the lower arm side. Heat can be transferred to the case 10. The top plate portion 3b and the leg portion 3a of the third electrode 3 serve as a heat transfer path, and from the other side of the semiconductor elements 6a, 6c (7a, 7c) on the lower arm side (opposite the case), the semiconductor elements 6a, The heat of 6c (7a, 7c) can be transferred to the case 10. Therefore, heat can be transferred to the case 10 from both sides of the semiconductor elements 6a and 6c (7a and 7c).

  As shown in FIGS. 3A and 3B, the upper arm side semiconductor element 4a disposed on the first electrode 1a and the lower arm side disposed on the adjacent first electrode 1b. When the semiconductor element 6b faces each other, the second electrode 2 cannot be a common electrode of the semiconductor element 4a and the semiconductor element 6b. Separate second electrodes 2 are provided for the semiconductor element 4a and the semiconductor element 6b. Also, if the lower arm side semiconductor element 6a disposed on the first electrode 1a and the upper arm side semiconductor element 4c disposed on the adjacent first electrode 1c are opposed to each other, The electrode 3 cannot be a common electrode of the semiconductor element 6a and the semiconductor element 4c. Separate third electrodes 3 are provided for the semiconductor element 6a and the semiconductor element 4c. For this reason, in this case, a gap is generated between the second electrode 2 for the semiconductor element 4a and the second electrode 2 for the semiconductor element 6b. A gap is generated between the third electrode 3 for the semiconductor element 6a and the third electrode 3 for the semiconductor element 4c. Therefore, the heat transfer path from the other side of the semiconductor element (the side opposite to the case) to the case 10 is narrowed, and the heat transfer characteristics are deteriorated.

  Accordingly, in the present embodiment, as shown in FIG. 1A, the upper arm side semiconductor element 4a disposed on the first electrode 1a and the upper arm side disposed on the adjacent first electrode 1b. The semiconductor elements 4b are arranged so as to face each other. Thereby, the 2nd electrode 2 can be made into the common electrode of the semiconductor element 4a and the semiconductor element 4b, and the heat-transfer characteristic from the other side (side opposite to a case) of a semiconductor element to the case 10 improves. Further, the lower arm side semiconductor element 6a disposed on the first electrode 1a and the lower arm side semiconductor element 6c disposed on the adjacent first electrode 1c are disposed to face each other. . Thereby, the third electrode 3 can be a common electrode of the semiconductor element 6a and the semiconductor element 6c, and the heat transfer characteristic from the other side (opposite side of the case) of the semiconductor element to the case 10 is improved.

-Effects-
According to the present embodiment, a semiconductor element on one first electrode 1a faces a semiconductor element on another adjacent first electrode 1b (or 1c). The second electrode 2 (or the third electrode 3) is arranged so as to straddle the semiconductor elements of both the first electrodes 1a, 1b (or 1c). The second electrode 2 (or the third electrode 3) has a portion (leg part 2a or 3a) extending toward the inner wall of the case between both the first electrodes, and the case via the insulating member 9 10 inner walls are joined. Therefore, the heat transfer characteristics from the semiconductor element to the case 10 are increased, thereby improving the heat transfer characteristics and improving the cooling efficiency (cooling performance) of the semiconductor element of the power converter.

  The upper arm side semiconductor element 4a disposed on the first electrode 1a and the upper arm side semiconductor element 4b disposed on the adjacent first electrode 1b are disposed to face each other. The lower arm side semiconductor element 6a arranged on the first electrode 1a and the lower arm side semiconductor element 6c arranged on the adjacent first electrode 1c are arranged so as to face each other. Thus, the second electrode 2 can be a common electrode for the semiconductor elements 4a and 4b, and the third electrode 3 can be a common electrode for the semiconductor elements 6a and 6c, further improving heat transfer characteristics. .

  Each semiconductor element and each electrode are arranged in parallel to the mounting surface of the case 10. For this reason, heat can be efficiently transferred to the case 10, and the cooling performance of the semiconductor element can be satisfied without increasing the size of the power converter.

<Second embodiment>
In the second embodiment, as shown in FIGS. 4A and 4B, the flat semiconductor elements (semiconductor element chips) and the flat electrodes are arranged perpendicular to the mounting surface of the case. The The first electrode 1, the conductive bonding member 8, the semiconductor elements 4 and 6, and the second or third electrodes 2 and 3 are stacked in a direction parallel to the case surface (mounting surface) on which the power module is mounted. Has been. Other configurations are the same as those in the first embodiment.

  The first electrode 1 is sandwiched between an upper arm switching semiconductor element 4 (first semiconductor element) and a lower arm switching semiconductor element 6 (third semiconductor element). The upper arm side switching semiconductor element 4 and the upper arm side reflux current semiconductor element 5 (second semiconductor element) are bonded to one surface of the first electrode 1 directly or via the conductive bonding member 8. Is done. The lower arm side switching semiconductor element 6 and the lower arm side reflux current semiconductor element 7 (fourth semiconductor element) are bonded to the other surface of the first electrode 1 directly or through the conductive bonding member 8. Is done.

  The upper arm side semiconductor elements 4a and 4b (5a and 5b) respectively disposed on the adjacent first electrodes 1a and 1b face each other with the second electrode 2 interposed therebetween. The lower arm side semiconductor elements 6a and 6c (7a and 7c) respectively disposed on the adjacent first electrodes 1a and 1c oppose each other with the third electrode 3 interposed therebetween. The first, second, and third electrodes 1, 2, and 3 are in contact with or bonded to the case 10 via the insulating member 9. The second electrode 2 extends toward the inner wall of the case 10 between the first electrodes 1a and 1b. The third electrode 3 extends toward the inner wall of the case 10 between the first electrodes 1a and 1c.

  The second electrode 2 is disposed so as to straddle the semiconductor elements 4a, 4b (5a, 5b) on the upper arm side adjacent to each other. That is, the second electrode 2 is disposed on the semiconductor element 4a (5a) and the semiconductor element 4b (5b).

  The third electrode 3 is disposed so as to straddle the semiconductor elements 6a and 6c (7a and 7c) on the lower arm side adjacent to each other. That is, the third electrode 3 is disposed on the semiconductor element 6a (7a) and the semiconductor element 6c (7c).

  According to this embodiment, each semiconductor element and each electrode are arranged perpendicular to the mounting surface of the case. For this reason, a power converter can be reduced in size, satisfying the cooling performance of a semiconductor element.

<Third embodiment>
In the third embodiment, as shown in FIG. 5, the power module 18 is attached to the wall surface 10 b perpendicular to the axial direction of the motor 50. The wall surface 10 b is an inner surface of the lid portion 10 c (shaft end portion) at the shaft end of the case 10. Case 10 accommodates motor 50 and power converter 100.

  In FIG. 5, the power module 18 is joined to the back of the cover 10 c at the shaft end of the case 10 via the insulating member 9 on the first electrode 1 side. The power module 18 is connected to the motor driver circuit board 11 that controls the operation of the switching semiconductor element. The first electrode 1 is connected to the motor coil 13. The second electrode 2 is connected to the positive electrode side of the DC power source. The third electrode 3 is connected to the negative electrode side of the DC power source.

  A stator 14 is joined to the inner peripheral surface of the side portion of the case 10. The rotor 15 and the shaft 16 are disposed in the stator 14 via a gap. The shaft 16 is rotatably supported by the case 10 via a bearing 17.

  Fig.6 (a) is the figure which looked at the power converter 100 to the axial direction from the motor side. In FIG. 1A of the first embodiment, the first electrode 1, the second electrode 2, the third electrode 3, and the semiconductor elements 4 and 6 are arranged linearly. However, in the third embodiment, as shown in FIG. 6A, the first electrode 1, the second electrode 2, the third electrode 3, the semiconductor elements 4 and 6 (or the semiconductor elements 5 and 7) are It is arranged along the circumferential direction of the motor 50. The first electrode 1 is disposed on the side near the case 10, and the second electrode 2 is disposed on the side far from the case 10.

  The switching semiconductor element 4 on the upper arm side having a large calorific value is arranged on the outer side in the radial direction than the semiconductor element 5 on the upper arm side having a small calorific value (watt: W). That is, the switching semiconductor element 4 is disposed on the outer peripheral side of the shaft end cover portion 10c of the case 10, and the return current semiconductor element 5 is disposed on the inner peripheral side of the shaft end cover portion 10c.

  In addition, the switching semiconductor element 6 on the lower arm side having a large calorific value is arranged on the outer side in the radial direction than the semiconductor element 7 on the lower arm side having a small calorific value. That is, the switching semiconductor element 6 is disposed on the outer peripheral side of the shaft end lid portion 10c of the case 10, and the return current semiconductor element 7 is disposed on the inner peripheral side of the shaft end lid portion 10c.

  As shown in FIG. 6B, as in the first embodiment, the first electrode 1 serves as a heat transfer path, and the heat of the semiconductor elements 4 and 6 from one side (case side) of the semiconductor elements 4 and 6. Can be transmitted to the case 10. The second electrode 2 and the third electrode 3 serve as a heat transfer path, and the heat of the semiconductor elements 4 and 6 can be transferred to the case 10 from the other side of the semiconductor elements 4 and 6 (the side opposite to the case). Therefore, the heat of the semiconductor elements 4 and 6 can be transferred to the case 10 from both sides.

  According to this embodiment, each semiconductor element and each electrode are mounted on the wall surface 10b of the case perpendicular to the axial direction of the rotating electrical machine. Thereby, a power converter becomes difficult to receive the influence of the heat from a motor. On the electrode, the semiconductor element having a large calorific value is arranged outside the other semiconductor elements having a small calorific value in the radial direction of the rotating electrical machine. As described above, since the semiconductor element generating a large amount of heat is arranged on the outer peripheral portion having a large mounting area, the semiconductor element and further the power converter can be efficiently cooled.

<Fourth embodiment>
In the fourth embodiment, unlike the third embodiment, the second electrode 2 and the third electrode 3 are arranged on the side closer to the case 10, and the first electrode 1 is arranged on the side far from the case 10. Other configurations are the same as those of the third embodiment.

  In FIG. 7, the power module 18 is joined to the back of the lid portion 10 c (shaft end portion) at the shaft end of the case 10 via the insulating member 9 on the second and third electrodes 2 and 3 side. The power module 18 is connected to the motor driver circuit board 11. The first electrode 1 is connected to the motor coil 13. The second electrode 2 is connected to the positive electrode side of the DC power source. The third electrode 3 is connected to the negative electrode side of the DC power source.

  A stator 14 is joined to the inner periphery of the case 10. The rotor 15 and the shaft 16 are disposed in the stator 14 via a gap. The shaft 16 is rotatably supported by the case 10 via a bearing 17.

  FIG. 8A is a diagram of the power converter 100 viewed from the motor side in the axial direction. The first electrode 1, the second electrode 2, the third electrode 3, and the semiconductor elements 4 and 6 (or the semiconductor elements 5 and 7) are arranged along the circumferential direction of the motor 50.

  The switching semiconductor element 4 on the upper arm side that generates a large amount of heat is disposed on the outer side in the radial direction than the semiconductor element 5 on the upper arm side that generates a small amount of heat. That is, the switching semiconductor element 4 is disposed on the outer peripheral side of the shaft end cover portion 10c of the case 10, and the return current semiconductor element 5 is disposed on the inner peripheral side.

  In addition, the switching semiconductor element 6 on the lower arm side having a large calorific value is arranged on the outer side in the radial direction than the semiconductor element 7 on the lower arm side having a small calorific value. That is, the switching semiconductor element 6 is disposed on the outer peripheral side of the shaft end cover portion 10c of the case 10, and the return current semiconductor element 7 is disposed on the inner peripheral side.

  As shown in FIG. 8B, the second electrode 2 and the third electrode 3 serve as a heat transfer path, and the heat of the semiconductor elements 4 and 6 is transferred from one side (case side) of the semiconductor elements 4 and 6 to the case. 10 can be transmitted.

  The first electrode 1 is not in contact with the second electrode 2 and the third electrode 3. However, heat radiation from the first electrode 1 to the second electrode 2 and the third electrode 3 causes the first electrode 1, the second electrode 2, and the third electrode 3 to be a heat transfer path. Therefore, the heat of the semiconductor elements 4 and 6 can be transferred to the case 10 also from the other side of the semiconductor elements 4 and 6 (the side opposite to the case). Therefore, heat can be transferred from both sides of the semiconductor elements 4 and 6 to the case 10.

  According to this embodiment, as in the third embodiment, the power converter is less susceptible to the heat from the motor. Furthermore, since the semiconductor element generating a large amount of heat is disposed on the outer peripheral portion having a large mounting area, the semiconductor element and further the power converter can be efficiently cooled.

<Fifth embodiment>
In the fifth embodiment, as shown in FIG. 9, unlike the third embodiment, the power module 18 is attached to the wall surface 10 d parallel to the axial direction of the motor 50. The wall surface 10 d is an inner peripheral surface of the cylindrical side portion 10 e of the case 10.

  The power module 18 is joined to the inner peripheral surface (inner wall) of the cylindrical side portion 10 e of the case 10 via the insulating member 9 on the second and third electrode sides 2 and 3. The power module 18 is connected to the motor driver circuit board 11. The first electrode 1 is connected to the motor coil 13. The second electrode 2 is connected to the positive electrode side of the DC power source. The third electrode 3 is connected to the negative electrode side of the DC power source.

  A stator 14 is joined to the inner peripheral surface of the side portion of the case 10. The rotor 15 and the shaft 16 are disposed in the stator 14 via a gap. The shaft 16 is rotatably supported by the case 10 via a bearing 17. The second electrode 2 and the third electrode 3 are arranged on the side close to the side part 10 e of the case 10, and the first electrode 1 is arranged on the side far from the side part 10 e of the case 10.

  The circulating current semiconductor elements 5 and 7 with a small amount of heat generation are arranged on the rotating electrical machine side that generates heat, and the switching semiconductor elements 4 and 6 with a large amount of heat generation are arranged on the opposite side to the rotating electrical machine that generates heat.

  10, unlike FIG. 9, the second electrode 2 and the third electrode 3 are arranged on the side far from the side portion 10 e of the case 10, and the first electrode 1 is the side portion of the case 10. It may be arranged on the side close to 10e. In this case, the first electrode side 1 of the power module 18 is joined to the inner peripheral surface of the cylindrical side portion 10 e of the case 10 via the insulating member 9.

  According to this embodiment, since each semiconductor element and each electrode are mounted on the wall surface of the case parallel to the axial direction of the rotating electrical machine, the heat dissipation area can be increased. Since the semiconductor element having a large amount of heat generation is disposed on the side opposite to the rotating electric machine, and the semiconductor element having a small amount of heat generation is disposed on the rotating electric machine side, the cooling efficiency is improved.

<Sixth embodiment>
In the sixth embodiment, as shown in FIGS. 11A and 11B, the upper arm side semiconductor elements 4 and 5 and the lower arm side semiconductor elements 6 and 7 are directly or directly on one surface of the first electrode 1. Bonded via the conductive bonding member 8. The semiconductor elements 4 and 5 on the upper arm side are bonded to the second electrode 2 on the upper arm side directly or via a conductive bonding member. The semiconductor element 6 and the semiconductor element 7 on the lower arm side are joined to the third electrode 3 on the lower arm side directly or via a conductive joining member.

  On the first electrode 1, a switching semiconductor element group (first semiconductor element 4 and third semiconductor element 6) and a current refluxing semiconductor element group (second semiconductor element 5 and fourth semiconductor element) 7) are arranged in the arrangement direction. An upper arm side semiconductor element group and a lower arm side semiconductor element group on one first electrode 1 are an upper arm side semiconductor element group and a lower arm side semiconductor element group on another adjacent first electrode 1; They are arranged in plane symmetry.

  The upper arm side semiconductor elements 4a and 4b (5a and 5b) respectively disposed on the first electrodes 1a and 1b adjacent to each other face each other with the leg portion 2a of the second electrode 2 interposed therebetween. The second electrode 2 is disposed so as to straddle the semiconductor elements 4a, 4b (5a, 5b) on the upper arm side adjacent to each other. That is, the top plate portion 2b of the second electrode 2 is disposed on the semiconductor element 4a (5a) and the semiconductor element 4b (5b). The insulating member 9, the first electrode 1, the conductive bonding member 8, the semiconductor element 4, and the top plate portion 2b of the second electrode 2 are stacked in a direction perpendicular to the case surface (mounting surface) on which the power module is mounted. Has been.

  The lower arm side semiconductor elements 6a and 6c (7a and 7c) respectively disposed on the adjacent first electrodes 1a and 1c oppose each other with the leg 3a of the third electrode 3 interposed therebetween. The third electrode 3 is disposed so as to straddle the semiconductor elements 6a and 6c (7a and 7c) on the lower arm side adjacent to each other. That is, the top plate portion 3b of the third electrode 3 is disposed on the semiconductor element 6a (7a) and the semiconductor element 6c (7c). The insulating member 9, the first electrode 1, the conductive bonding member 8, the semiconductor element 6, and the top plate portion 3b of the third electrode 3 are stacked in a direction perpendicular to the case surface (mounting surface) on which the power module is mounted. Has been.

  The pair of first semiconductor elements 4 on the upper arm side facing each other with the leg part 2a of the second electrode 2 interposed therebetween, and the second semiconductor element 5 on the upper arm side facing each other with the leg part 2a of the second electrode 2 interposed therebetween. Are alternately arranged in the arrangement direction. A pair of third semiconductor elements 6 on the lower arm side facing each other across the leg 3a of the third electrode 3 and a fourth semiconductor element 7 on the lower arm side facing each other across the leg 3a of the third electrode 3 Are alternately arranged in the arrangement direction.

  The leg 2a between the first electrodes 1a, 1b (1a, 1c) of the second electrode 2 extends toward the inner wall of the case 10 and contacts or joins the case 10 via the insulating member 9. ing. The leg 3a between the first electrodes 1a, 1c (1a, 1b) of the third electrode 3 extends toward the inner wall of the case 10, and contacts or joins the case 10 via the insulating member 9. ing.

  According to the present embodiment, all the first and second semiconductor elements 4 and 5 on the plurality of first electrodes 1 are arranged in a straight line, and all the first and second semiconductor elements are straddled. Two electrodes 2 are arranged. All the third and fourth semiconductor elements on the plurality of first electrodes 1 are arranged in a straight line, and the third electrode 3 is arranged so as to straddle all the third and fourth semiconductor elements 6 and 7. The Since the single second electrode 2 and the single third electrode 3 may be provided, the structure of the power converter becomes simple and the manufacture becomes easy.

  The present invention is not limited to the embodiments described above, and various modifications and changes can be made within the scope of the technical idea, and it is obvious that these are also included in the technical scope of the present invention. .

DESCRIPTION OF SYMBOLS 1 1st electrode 2 2nd electrode 3 3rd electrode 4 1st semiconductor element 5 2nd semiconductor element 6 3rd semiconductor element 7 4th semiconductor element 9 Insulating member 10 Case 18 Power module 50 Rotating electrical machinery 100 Power conversion Machine

Claims (7)

A power converter that is mounted on a case in which a rotating electrical machine is housed via an insulating member,
A plurality of first electrodes;
A first semiconductor element for switching joined to each first electrode;
A second semiconductor element for reflux current joined to each first electrode;
A second electrode joined to the first semiconductor element and the second semiconductor element,
At least one semiconductor element on one first electrode is opposed to at least one semiconductor element on another adjacent first electrode, and straddles the first and second semiconductor elements of both first electrodes. The second electrode is disposed;
The second electrode has a portion extending toward the case between the first electrodes, and is joined to an inner wall of the case via the insulating member. Machine.   The power converter according to claim 1, wherein each semiconductor element and each electrode are arranged in parallel to the mounting surface of the case.   The power converter according to claim 1, wherein each semiconductor element and each electrode are arranged perpendicular to the mounting surface of the case. Each semiconductor element and each electrode are mounted on the wall surface of the case perpendicular to the axial direction of the rotating electrical machine,
On the first electrode and the second electrode, one of the first semiconductor element and the second semiconductor element that has a larger calorific value is on the outer side in the radial direction of the rotating electrical machine than the other that has a smaller calorific value. The power converter according to claim 2 or 3, wherein the power converter is arranged. Each semiconductor element and each electrode are mounted on the wall surface of the case parallel to the axial direction of the rotating electrical machine,
On the first electrode and the second electrode, one of the first semiconductor element and the second semiconductor element that has a small heat generation amount is disposed on the rotating electrical machine side, and the other that has a large heat generation amount is the rotating electrical machine. The power converter according to claim 2, wherein the power converter is disposed on a side opposite to the power converter. The first semiconductor element and the second semiconductor element are upper arm side semiconductor elements,
The power converter is
A third semiconductor element for switching on the lower arm side joined to each first electrode;
A fourth semiconductor element for reflux current on the lower arm side joined to each first electrode;
A third electrode joined to the third semiconductor element and the fourth semiconductor element on the lower arm side, and
At least one semiconductor element on the lower arm side on the one first electrode is opposed to at least one semiconductor element on the lower arm side on the other adjacent first electrode, The third electrode is disposed so as to straddle the fourth semiconductor element,
The third electrode has a portion extending toward the case between the first electrodes adjacent to each other, and is joined to the case via the insulating member. Power converter.   All the first and second semiconductor elements on the plurality of first electrodes are linearly arranged, and the second electrode is arranged so as to straddle all the first and second semiconductor elements. The power converter according to claim 1.

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