Power conversion device

Abstract

The present invention provides a power conversion device. The power conversion device (100) comprises: a main circuit substrate (5); a terminal block (4); and a resin-molded bus bar (10, 210) which is integrally resin-molded in a manner that a plate-shaped first bus bar (11) and a plate-shaped second bus bar (12) are insulated by using an insulating resin (13, 213). The resin-molded bus bar (10, 110) is formed in the shape of a letter L and has a lateral portion (10a) extending along the main circuit substrate (5) and an up-down portion (10b) extending upward from the lateral portion (10a) toward the terminal block (4).

Description

Technical Field

[0001] The present invention relates to a power conversion device, and more particularly to a power conversion device including a terminal block and a bus bar connected to the terminal block. The terminal block is arranged above a circuit substrate and connected to wiring from outside the device. Background Art

[0002] Conventionally, there is known a power conversion device including a terminal block disposed above a circuit board and connected to wiring from outside the device and a bus bar connected to the terminal block. Such a power conversion device is disclosed in, for example, Japanese Patent Application Publication No. 2017-77087.

[0003] Japanese Patent Application Publication No. 2017-77087 discloses a power conversion device having a terminal block disposed above a circuit board and connected to wiring from outside the device and a bus bar connected to the terminal block. In the power conversion device, a semiconductor module having a built-in semiconductor element for power conversion is connected (mounted) to the circuit board.

[0004] Here, although it is not clearly described in the above-mentioned Japanese Patent Application Publication No. 2017-77087, in the conventional power conversion device described in the above-mentioned Japanese Patent Application Publication No. 2017-77087, a terminal block and a circuit board are connected by a plurality of bus bars. In such a case, when the space for routing the plurality of bus bars on the surface of the circuit board is small, the plurality of bus bars are arranged to be separated from each other in the vertical direction in order to prevent short circuits between the plurality of bus bars.

[0005] However, in the case where a plurality of bus bars are arranged to be separated from each other in the vertical direction, in order to prevent a short circuit between the plurality of bus bars, the bus bars need to be separated from each other in the vertical direction by an amount corresponding to the air insulation distance (insulation distance when insulation is performed using air), and there is a problem of an increase in the size of the device in the vertical direction on the circuit board. In addition, there is also a method of reducing the distance between the bus bars in the vertical direction by installing the bus bars in a manner such that an insulating member serving as another member is interposed between the plurality of bus bars, but in such a method, there is a problem of reduced workability during assembly due to an increase in the number of components and complication of assembly. Therefore, a power conversion device is desired that can suppress a reduction in workability during assembly and suppress an increase in the size of the device in the vertical direction. Summary of the invention

[0006] Problem that the invention aims to solve

[0007] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide a power conversion device capable of suppressing a decrease in workability during assembly and suppressing an increase in the size of the device in the vertical direction.

[0008] Solutions for solving problems

[0009] In order to achieve the above-mentioned purpose, a technical solution of the present invention provides a power conversion device, wherein the power conversion device comprises: a main circuit substrate, which is equipped with a semiconductor component for power conversion; a terminal block, which is arranged above the main circuit substrate and connected to wiring from outside the device; and a resin-molded bus bar, which is resin-molded as a whole in a manner of insulating a plate-shaped first bus bar and a plate-shaped second bus bar using an insulating resin, the first bus bar and the second bus bar are connected to the terminal block and electrically connected to the main circuit substrate or the semiconductor component for power conversion, and the resin-molded bus bar is formed into a letter L shape having a lateral portion extending along the main circuit substrate and an up-down portion extending upward from the lateral portion toward the terminal block side.

[0010] In the power conversion device of the above-mentioned technical solution, as described above, the resin-molded busbar is formed into a letter L shape having a lateral portion extending along the main circuit substrate and a vertical portion extending upward from the lateral portion toward the terminal block side. In addition, the resin-molded busbar is integrally resin-molded in a manner that the first busbar and the second busbar are insulated by an insulating resin. Thus, the insulating resin insulates the first busbar from the second busbar, so that even when the first busbar and the second busbar overlap in the vertical direction, the distance between the first busbar and the second busbar can be made smaller in the lateral portion extending along the main circuit substrate compared to the case of insulation using air (air insulation). As a result, it is possible to suppress the increase in the vertical size on the main circuit substrate of the power conversion device. In addition, by extending the lateral portion of the resin-molded busbar, which is a single component formed by integrally resin-molding the first busbar, the second busbar, and the insulating resin, along the main circuit substrate, the first busbar and the second busbar can be easily electrically connected to the main circuit substrate or the semiconductor component for power conversion. And, by extending the vertical portion of the resin-molded busbar, which is a single component formed by integrally resin-molding the first busbar, the second busbar, and the insulating resin, upward from the lateral portion toward the terminal block side, the first busbar and the second busbar can be easily electrically connected to the terminal block arranged above the main circuit substrate. Thus, by using the resin-molded busbar, which is a single component formed in the shape of the letter L having a lateral portion and a vertical portion, the first busbar and the second busbar can be easily electrically connected to the main circuit substrate or the semiconductor component for power conversion and the terminal block arranged above the main circuit substrate. As a result, unlike the case where the first bus bar and the second bus bar are mounted by sandwiching an insulating member as another member, an increase in the number of components and complication of assembly can be suppressed. As a result, a decrease in workability during assembly and an increase in the size of the device in the vertical direction can be suppressed.

[0011] In the power conversion device of the above-mentioned technical solution, it is preferred that the resin-molded busbar is configured such that an insulating resin is interposed between the first busbar and the second busbar, and the first busbar and the second busbar are stacked in a state of being separated from each other by a first separation distance that is smaller than the air insulation distance. If so configured, even when the first busbar and the second busbar are overlapped in the vertical direction, since the insulating resin is sandwiched between the first busbar and the second busbar, the first busbar and the second busbar can be reliably insulated. As a result, the distance between the first busbar and the second busbar can be made smaller than the air insulation distance, so that the increase in the vertical size on the main circuit substrate of the power conversion device can be suppressed.

[0012] In the structure in which the first bus bar and the second bus bar are stacked in a state of being separated from each other by a first separation distance smaller than the air insulation distance, it is preferred that the terminal block includes a DC terminal block, the first bus bar has a positive electrode connection portion, the positive electrode connection portion is exposed from the insulating resin and connected to the positive terminal of the DC terminal block, the second bus bar has a negative electrode connection portion, the negative electrode connection portion is exposed from the insulating resin and connected to the negative terminal of the DC terminal block, and the first bus bar and the second bus bar are configured so that currents flow in opposite directions to each other. If so configured, currents in opposite directions flow in the first bus bar and the second bus bar, so that magnetic fields generated by the currents flowing in the first bus bar and the second bus bar can be offset from each other. As a result, the inductance of the first bus bar and the second bus bar can be reduced.

[0013] In this case, it is preferred that the power conversion device further includes a power substrate, which is arranged above the main circuit substrate and carries electronic components for generating a control power supply, the resin-molded bus bar is formed in a manner that the outer surface of the first bus bar and the outer surface of the second bus bar are covered with an insulating resin, the first bus bar is arranged between the main circuit substrate and the power substrate in a state where the first bus bar is separated from the power substrate by a second separation distance smaller than the air insulation distance in a lateral portion covered with the insulating resin, and the second bus bar is arranged between the main circuit substrate and the power substrate in a state where the second bus bar is separated from the main circuit substrate by a third separation distance smaller than the air insulation distance in a lateral portion covered with the insulating resin. If so configured, the first bus bar is arranged between the main circuit substrate and the power substrate in a state where the first bus bar is separated from the power substrate by a second separation distance smaller than the air insulation distance in a lateral portion covered with the insulating resin, thereby being able to reduce the distance between the first bus bar and the power substrate. In addition, the second bus bar is arranged between the main circuit substrate and the power substrate in a state where the second bus bar is separated from the main circuit substrate by a third separation distance smaller than the air insulation distance in the lateral portion covered by the insulating resin, thereby reducing the distance between the second bus bar and the main circuit substrate. As a result, the distance between the main circuit substrate and the power substrate arranged so as to sandwich the first bus bar and the second bus bar can be reduced, thereby suppressing the increase in the size in the vertical direction on the main circuit substrate.

[0014] In the structure having the power substrate described above, it is preferred that the first bus bar has: a first main circuit substrate connection portion exposed from the insulating resin and connected to the main circuit substrate; and a power substrate connection portion exposed from the insulating resin and connected to the power substrate. If so configured, the first bus bar whose outer surface is covered with the insulating resin can be easily connected to the main circuit substrate by using the first main circuit substrate connection portion exposed from the insulating resin. In addition, the first bus bar whose outer surface is covered with the insulating resin can be easily connected to the power substrate by using the power substrate connection portion exposed from the insulating resin.

[0015] In this case, it is preferred that the first bus bar is configured to have a step shape bent toward the main circuit substrate side, the first main circuit substrate connection portion is connected to the main circuit substrate from above the main circuit substrate, and the power supply substrate connection portion of the first bus bar is configured to have a step shape bent toward the power supply substrate side and is connected to the power supply substrate from below the power supply substrate. If configured in this way, even when the lateral portion of the first bus bar covered with insulating resin is separated from the main circuit substrate by an amount corresponding to the air insulation distance, the first main circuit substrate connection portion of the first bus bar can be brought close to the main circuit substrate side (the height position is brought close) by the step shape of the first bus bar bent toward the main circuit substrate side. As a result, the first main circuit substrate connection portion of the first bus bar can be easily connected to the main circuit substrate. In addition, even when the lateral portion of the first bus bar covered with insulating resin is separated from the power supply substrate by an amount corresponding to the air insulation distance, the power supply substrate connection portion can be brought close to the power supply substrate side (the height position is brought close) by the step shape of the power supply substrate connection portion bent toward the power supply substrate side. As a result, the power-substrate connecting portion of the first bus bar can be easily connected to the power-substrate.

[0016] In the power conversion device of the above-mentioned technical solution, it is preferred that the second bus bar has a second main circuit substrate connection portion, the second main circuit substrate connection portion is exposed from the insulating resin and connected to the main circuit substrate, the first bus bar is arranged above the second bus bar in the lateral portion of the resin-molded bus bar, and the first bus bar is formed in a circuitous manner so as not to overlap with the second main circuit substrate connection portion of the second bus bar when viewed from above. If so configured, even if the first bus bar is arranged above the second bus bar in the lateral portion of the resin-molded bus bar, the second main circuit substrate connection portion of the second bus bar can be easily screwed (fastened) to the main circuit substrate from above.

[0017] In the power conversion device of the above-mentioned technical solution, it is preferred that the vertical direction portion of the resin-molded bus bar is configured such that the thickness in the direction where the first bus bar and the second bus bar overlap becomes smaller as it goes upward from the lateral portion side. If configured in this way, when manufacturing the resin-molded bus bar, the resin-molded bus bar after resin molding can be easily removed from the molding mold. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a diagram showing an example of a circuit configuration of a power conversion device according to an embodiment of the present invention.

[0019] Figure 2 It is a perspective view for explaining the structure of the power conversion device.

[0020] Figure 3 It is a perspective view for explaining the structure of a resin-molded bus bar.

[0021] Figure 4 It is a diagram showing the arrangement of the resin molded bus bars as viewed from above.

[0022] Figure 5 It is along Figure 4 A partial cross-sectional view of the 200-200 line.

[0023] Figure 6 It is a perspective view for explaining the structure of a resin-molded bus bar according to a modified example. DETAILED DESCRIPTION

[0024] Hereinafter, embodiments of the present invention will be described based on the drawings.

[0025] (Overall structure of power conversion device)

[0026] Reference Figure 1 and Figure 2 The overall structure of the power conversion device 100 of this embodiment will be described. Figure 1 As shown, the power conversion device 100 is an inverter including an inverter circuit unit 1 including a switching element 1 a , a rectifier circuit unit 2 including a diode element 2 a , and a smoothing circuit unit 3 including a smoothing capacitor 3 a .

[0027] In addition, if Figure 1 As shown in FIG. 1 , the power conversion device 100 includes a terminal block 4 to which wiring from outside the device is connected. The terminal block 4 includes a DC terminal block 41 . The terminal block 4 also includes an output terminal block 42 and an input terminal block 43 .

[0028] In addition, if Figure 2As shown, the power conversion device 100 includes a main circuit substrate 5 on which a semiconductor component 50 is mounted (installed). In addition, the semiconductor component 50 is an example of a "semiconductor component for power conversion" described in the claims. The semiconductor component 50 contains semiconductor elements for power conversion (switching element 1a and diode element 2a). In addition, capacitors and relays (not shown) are provided on the main circuit substrate.

[0029] In addition, if Figure 2 As shown, the power conversion device 100 includes a power substrate 6, which is arranged above the main circuit substrate 5 (Z1 direction side) and carries (mounts) electronic components (components 61) for generating control power. That is, the power substrate 6 and the electronic components carried (mounted) on the power substrate 6 generate the power for controlling the power conversion circuit (inverter circuit unit 1). In addition, the power substrate 6 may also carry (mount) electronic components for constituting a detection circuit not shown.

[0030] The main circuit board 5 and the power board 6 are printed circuit boards (PCBs) that are formed with wiring patterns using conductors and on which electronic components are mounted (installed). The main circuit board 5 and the power board 6 are formed in a manner extending along the X direction and the Y direction (XY plane). In addition, in this specification, the up-down direction is defined as the Z direction, the direction perpendicular to the up-down direction (Z direction) is defined as the X direction, and the direction perpendicular to the Z direction and the X direction is defined as the Y direction. Figure 2 In the figure, only a part of the power substrate 6 on the Y2 direction side is shown by a solid line, but in fact, as shown by a dotted line, the power substrate 6 is formed so as to extend to the vicinity of the end on the Y1 direction side of the main circuit substrate 5. The power substrate 6 is formed so as to cover the main circuit substrate 5 and a lateral portion 10a of a resin-molded bus bar 10 described later.

[0031] like Figure 2 As shown, a semiconductor component 50 is mounted (installed) on the back side (Z2 direction side) of the main circuit substrate 5. In addition, in order to electrically connect to the wiring pattern of the main circuit substrate 5 or the semiconductor component 50, the main circuit substrate 5 includes a plurality of connection terminals 51 provided on the surface side (Z1 direction side) of the main circuit substrate 5.

[0032] In addition, the power conversion device 100 includes an output terminal block 42 (see Figure 1 ) and the output bus bar 21 connected to the input terminal block 43 (see Figure 1 ) is connected to the input bus bar 31. In addition, the output bus bar 21 and the input bus bar 31 are connected to the connection terminals 51 of the main circuit substrate 5, respectively.

[0033] In addition, if Figure 2As shown, the terminal block 4 is arranged above the main circuit substrate 5 (Z1 direction side). In addition, the DC terminal block 41 and the output terminal block 42 are formed integrally. The terminal block 4 (the DC terminal block 41, the output terminal block 42 and the input terminal block 43) is formed of PBT (Polybutylene terephthalate) resin and is provided with a terminal for connecting to wiring outside the device.

[0034] In addition, if Figure 2 and Figure 3 As shown, the power conversion device 100 includes a resin molded bus bar 10, which is formed by using an insulating resin 13 (see Figure 3 ) The plate-shaped first bus bar 11 and the plate-shaped second bus bar 12 are integrally molded by resin in a manner that insulates the first bus bar 11 and the second bus bar 12.

[0035] like Figure 2 and Figure 3 As shown, the resin molded bus bar 10 is formed in a substantially L-shaped shape having a lateral portion 10a extending along the main circuit substrate 5 and an up-down portion 10b extending upward (in the Z1 direction) from the lateral portion 10a toward the terminal block 4. In addition, the lateral portion 10a is formed so as to extend from the up-down portion 10b toward the X2 direction.

[0036] like Figure 2 As shown, the first bus bar 11 and the second bus bar 12 are connected to the terminal block 4. In addition, the first bus bar 11 and the second bus bar 12 are electrically connected to the main circuit substrate 5 (semiconductor component 50). In this embodiment, the first bus bar 11 and the second bus bar 12 are connected to the main circuit substrate 5 via the connection terminal 51 (see Figure 2 ) is electrically connected to the semiconductor component 50.

[0037] In addition, if Figure 3 As shown, the resin molded bus bar 10 is formed by covering the outer surface of the first bus bar 11 and the outer surface of the second bus bar 12 with an insulating resin 13. The insulating resin 13 is, for example, PBT resin. In addition, as described later, the resin molded bus bar 10 is also provided with the insulating resin 13 between the first bus bar 11 and the second bus bar 12.

[0038] The first bus bar 11 is connected between the rectifier circuit unit 2 (diode element 2a) and the positive terminal 41a (see Figure 1 ) between the current path P (refer to Figure 1 ) is provided on the bus bar. The first bus bar 11 is a conductive plate-shaped member. For example, the first bus bar 11 is a copper bar.

[0039] like Figure 3As shown, the first bus bar 11 has a positive electrode connecting portion 11a, which is exposed from the insulating resin 13 and connected to the positive terminal 41a of the DC terminal block 41 (see Figure 1 )connect.

[0040] In addition, if Figure 3 As shown, the first bus bar 11 has a connection portion 11b which is exposed from the insulating resin 13 and connected to the main circuit board 5. The connection portion 11b is an example of a "first main circuit board connection portion" described in the claims.

[0041] In addition, if Figure 3 As shown, the first bus bar 11 has a connection portion 11c which is exposed from the insulating resin 13 and connected to the power board 6. The connection portion 11c is an example of a "power board connection portion" described in the claims.

[0042] The second bus bar 12 is used to connect the inverter circuit unit 1 (switching element 1a) and the smoothing circuit unit 3 (smoothing capacitor 3a) to the negative terminal 41b of the DC terminal block 41 (see Figure 1 ) of the current path N (refer to Figure 1 ) is provided on the bus bar. The second bus bar 12 is a conductive plate-shaped member. For example, the second bus bar 12 is a copper bar.

[0043] like Figure 3 As shown, the second bus bar 12 has a negative electrode connecting portion 12a, which is exposed from the insulating resin 13 and connected to the negative terminal 41b of the DC terminal block 41 (see Figure 1 The negative electrode connection portion 12 a of the second bus bar 12 is arranged on the Y1 direction side relative to the positive electrode connection portion 11 a of the first bus bar 11 .

[0044] In addition, if Figure 3 As shown, the second bus bar 12 has a connection portion 12b which is exposed from the insulating resin 13 and connected to the main circuit board 5. The connection portion 12b is an example of a "second main circuit board connection portion" described in the claims.

[0045] In addition, if Figure 4 As shown in FIG. 1 , the positive electrode connection portion 11a of the first bus bar 11 is fastened and fixed to the terminal block 4 (positive electrode terminal 41a) by means of a screw 71. Figure 4 As shown, the negative electrode connecting portion 12 a of the second bus bar 12 is fastened and fixed to the terminal block 4 (negative electrode terminal 41 b ) by means of a screw 72 .

[0046] In addition, if Figure 4As shown, when viewed from above (Z1 direction side), the connection portion 11b of the first bus bar 11 is arranged on the side (X2 direction side) opposite to the side where the smoothing capacitor 3a is arranged with respect to the connection portion 12b of the second bus bar 12.

[0047] In addition, if Figure 4 As shown, the first bus bar 11 is formed in a meandering manner so as not to overlap with the connecting portion 12 b of the second bus bar 12 when viewed from above (Z1 direction side).

[0048] like Figure 4 As shown, the resin molded bus bar 10 is formed in a manner of branching near the connection portion 12b of the second bus bar 12. The first bus bar 11 is formed so as to be bent toward the Y2 direction side at the X1 direction side of the connection portion 12b of the second bus bar 12 in a state where the outer surface is covered with the insulating resin 13. In addition, the first bus bar 11 is formed so as to extend toward the X2 direction side while being detoured so as not to overlap with the connection portion 12b of the second bus bar 12.

[0049] In addition, if Figure 4 As shown, the first bus bar 11 in a state where the outer surface is covered with the insulating resin 13 has a U-shape protruding toward the Y2 direction side when viewed from above (Z1 direction side). Furthermore, the connecting portion 12b of the second bus bar 12 is arranged inside the roughly U-shaped portion (part U) of the first bus bar 11 when viewed from above (Z1 direction side). In addition, the connecting portion 11c is formed to extend from the outside (Y2 direction side) of the roughly U-shaped portion (part U) of the first bus bar 11 toward the Y2 direction side.

[0050] In addition, if Figure 5 As shown in FIG. 1 , the first bus bar 11 is arranged above (on the Z1 direction side) the second bus bar 12 in the lateral portion 10a of the resin-molded bus bar 10. Figure 5 As shown, the second bus bar 12 is arranged closer to the terminal block 4 (X1 direction side) than the first bus bar 11 in the vertical direction portion 10 b of the resin molded bus bar 10 .

[0051] like Figure 5 As shown in FIG. 1 , the resin molded bus bar 10 is configured such that an insulating resin 13 is interposed between the first bus bar 11 and the second bus bar 12. In the lateral portion 10a and the vertical portion 10b of the resin molded bus bar 10, the insulating resin 13 is interposed between the first bus bar 11 and the second bus bar 12. The resin molded bus bar 10 is configured such that the first bus bar 11 and the second bus bar 12 are separated by a separation distance D1 (see FIG. 1 ) which is smaller than the air insulation distance. Figure 5) in a stacked state. In addition, the separation distance D1 is an example of the "first separation distance" described in the claims.

[0052] As described above, the first bus bar 11 is connected to the positive electrode terminal 41a of the DC terminal block 41 by the positive electrode connecting portion 11a (see Figure 1 ). In addition, the second bus bar 12 is connected to the negative terminal 41b of the DC terminal block 41 by the negative electrode connecting portion 12a (see Figure 1 ). Thus, in the first bus bar 11 and the second bus bar 12, it is configured that the current flows in the opposite directions to each other. In addition, in the vertical portion 10b and the lateral portion 10a of the resin-molded bus bar 10, the first bus bar 11 and the second bus bar 12 are stacked. As a result, in the portion where the first bus bar 11 and the second bus bar 12 are stacked in the vertical portion 10b and the lateral portion 10a, currents in opposite directions flow in the first bus bar 11 and the second bus bar 12, so that the magnetic fields generated by the currents flowing in the first bus bar 11 and the second bus bar 12 can cancel each other. As a result, in the resin-molded bus bar 10, in the portion where the first bus bar 11 and the second bus bar 12 are stacked in the vertical portion 10b and the lateral portion 10a, the inductance of the first bus bar 11 and the second bus bar 12 can be reduced.

[0053] In addition, the first bus bar 11 and the second bus bar 12 are separated from each other by a distance D1 (see Figure 5 ), but the separation distance D1 (the thickness of the insulating resin 13 between the first bus bar 11 and the second bus bar 12) can also be appropriately changed according to the magnitude of the current flowing in the first bus bar 11 and the second bus bar 12 and the electrical characteristics of the insulating resin 13. That is, the separation distance D1 (the thickness of the insulating resin 13 between the first bus bar 11 and the second bus bar 12) can be as follows: Figure 5 As shown, the thickness t1 of the first bus bar 11 and the thickness t2 of the second bus bar 12 are approximately the same, but may be larger or smaller than the thickness t1 of the first bus bar 11 and the thickness t2 of the second bus bar 12 .

[0054] In addition, the first bus bar 11 is separated from the power board 6 by a separation distance D2 (see FIG. 1 ) which is smaller than the air insulation distance in the lateral portion 10a covered with the insulating resin 13. Figure 5 ) is arranged between the main circuit board 5 and the power board 6. In addition, the separation distance D2 is an example of the "second separation distance" described in the claims.

[0055] Furthermore, the first bus bar 11 is configured to have a stepped shape bent toward the main circuit substrate 5 side (Z2 direction side) (see Figure 5), the connection portion 11b is connected to the main circuit substrate 5 from above (Z1 direction side) of the main circuit substrate 5. The connection portion 11b of the first bus bar 11 is connected to the main circuit substrate 5 by a screw 81 (see Figure 4 ) is connected to the connection terminal 51 of the main circuit substrate 5 from the Z1 direction side, and is electrically connected to the semiconductor element 50 via the connection terminal 51. In addition, the first bus bar 11 is electrically connected to the positive electrode side of the semiconductor element 50.

[0056] The connection portion 11c of the first bus bar 11 is configured to have a stepped shape bent toward the power substrate 6 side (Z1 direction side) (see FIG. Figure 3 and Figure 5 ), and connected to the power substrate 6 from below (Z2 direction side) the power substrate 6. The connecting portion 11c is connected to the conductor pattern of the power substrate 6 from the Z2 direction side, and is fastened and fixed by a screw 91.

[0057] In addition, the second bus bar 12 is separated from the main circuit board 5 by a separation distance D3 (see FIG. 1 ) which is smaller than the air insulation distance in the lateral portion 10a covered with the insulating resin 13. Figure 5 ) is arranged between the main circuit board 5 and the power supply board 6. In addition, the separation distance D3 is an example of the "third separation distance" described in the claims.

[0058] The second bus bar 12 is configured to have a stepped shape bent toward the main circuit board 5 side (Z2 direction side) (see Figure 5 ), the connecting portion 12b is connected to the main circuit substrate 5 from above (Z1 direction side) of the main circuit substrate 5. Figure 5 As shown, the connection portion 12b of the second bus bar 12 is connected to the connection terminal 51 of the main circuit board 5 from the Z1 direction side by the screw 82, and is electrically connected to the semiconductor element 50 via the connection terminal 51. The second bus bar 12 is electrically connected to the negative electrode side of the semiconductor element 50.

[0059] In addition, if Figure 5 As shown in FIG. 1 , the vertical portion 10b of the resin molded bus bar 10 is configured such that the thickness in the X direction (the direction in which the first bus bar 11 and the second bus bar 12 overlap) decreases (becomes tapered) as it goes from the lateral portion 10a side (Z2 direction side) toward the upper side (Z1 direction side). That is, the thickness t4 of the upper side (Z1 direction side) of the vertical portion 10b of the resin molded bus bar 10 is smaller than the thickness t3 of the lower side (Z2 direction side) of the vertical portion 10b.

[0060] (Effects of Embodiments)

[0061] In this embodiment, the following effects can be obtained.

[0062] In the present embodiment, the resin-molded bus bar 10 is formed in an L-shaped shape having a lateral portion 10a extending along the main circuit substrate 5 and a vertical portion 10b extending upward (Z1 direction side) from the lateral portion 10a toward the terminal block 4. In addition, the resin-molded bus bar 10 is integrally resin-molded in such a manner that the first bus bar 11 and the second bus bar 12 are insulated by the insulating resin 13. Thus, the insulating resin 13 insulates the first bus bar 11 from the second bus bar 12. Therefore, even when the first bus bar 11 and the second bus bar 12 are overlapped in the vertical direction (Z direction), the distance between the first bus bar 11 and the second bus bar 12 can be made smaller in the lateral portion 10a extending along the main circuit substrate 5 compared to the case of insulation by air (air insulation). As a result, it is possible to suppress the increase in the vertical size on the main circuit substrate 5 of the power conversion device 100. In addition, by extending the lateral portion 10a of the resin-molded bus bar 10, which is a single member formed by integrally molding the first bus bar 11, the second bus bar 12, and the insulating resin 13, along the main circuit substrate 5, both the first bus bar 11 and the second bus bar 12 can be easily electrically connected to the main circuit substrate 5 (semiconductor component 50). In addition, by extending the vertical portion 10b of the resin-molded bus bar 10, which is a single member formed by integrally molding the first bus bar 11, the second bus bar 12, and the insulating resin 13, upward (Z1 direction side) from the lateral portion 10a toward the terminal block 4 side, both the first bus bar 11 and the second bus bar 12 can be easily electrically connected to the terminal block 4 arranged above the main circuit substrate 5. Thus, by using the resin-molded bus bar 10 as a single member formed in the shape of the letter L having the lateral portion 10a and the vertical portion 10b, both the first bus bar 11 and the second bus bar 12 can be easily electrically connected to the main circuit substrate 5 (semiconductor component 50) and the terminal block 4 arranged above the main circuit substrate 5. As a result, unlike the case where the first bus bar 11 and the second bus bar 12 are mounted in a manner sandwiching an insulating member as another member, an increase in the number of components and complication of assembly can be suppressed. As a result, a decrease in workability during assembly can be suppressed and an increase in the size of the device in the vertical direction can be suppressed.

[0063] In addition, in the present embodiment, as described above, the resin-molded bus bar 10 is configured such that the insulating resin 13 is interposed between the first bus bar 11 and the second bus bar 12, and the first bus bar 11 and the second bus bar 12 are stacked in a state where they are separated from each other by a separation distance D1 that is smaller than the air insulation distance. Thus, even when the first bus bar 11 and the second bus bar 12 are overlapped in the vertical direction (Z direction), the first bus bar 11 and the second bus bar 12 can be reliably insulated because the insulating resin 13 is sandwiched between the first bus bar 11 and the second bus bar 12. As a result, the distance between the first bus bar 11 and the second bus bar 12 can be made smaller than the air insulation distance, so that the size increase in the vertical direction (Z direction) on the main circuit substrate 5 of the power conversion device 100 can be suppressed.

[0064] In addition, in the present embodiment, as described above, the first bus bar 11 has a positive electrode connection portion 11a exposed from the insulating resin 13 and connected to the positive terminal 41a of the DC terminal block 41. And, the second bus bar 12 has a negative electrode connection portion 12a exposed from the insulating resin 13 and connected to the negative terminal 41b of the DC terminal block 41. In addition, in the first bus bar 11 and the second bus bar 12, it is configured so that currents flow in opposite directions to each other. Thus, currents in opposite directions flow in the first bus bar 11 and the second bus bar 12, so that the magnetic fields generated by the currents flowing in the first bus bar 11 and the second bus bar 12 can cancel each other. As a result, the inductance of the first bus bar 11 and the second bus bar 12 can be reduced.

[0065] In addition, in the present embodiment, as described above, the resin molded bus bar 10 is formed in such a manner that the outer surface of the first bus bar 11 and the outer surface of the second bus bar 12 are covered with the insulating resin 13. And the first bus bar 11 is arranged between the main circuit substrate 5 and the power substrate 6 in a state where the first bus bar 11 is separated from the power substrate 6 by the separation distance D2 smaller than the air insulation distance in the lateral portion 10a covered by the insulating resin 13. In addition, the second bus bar 12 is arranged between the main circuit substrate 5 and the power substrate 6 in a state where the second bus bar 12 is separated from the main circuit substrate 5 by the separation distance D3 smaller than the air insulation distance in the lateral portion 10a covered by the insulating resin 13. Thus, the first bus bar 11 is arranged between the main circuit substrate 5 and the power substrate 6 in a state where the first bus bar 11 is separated from the power substrate 6 by the separation distance D2 smaller than the air insulation distance in the lateral portion 10a covered by the insulating resin 13, so that the distance between the first bus bar 11 and the power substrate 6 can be reduced. In addition, the second bus bar 12 is arranged between the main circuit substrate 5 and the power substrate 6 in a state where the second bus bar 12 is separated from the main circuit substrate 5 by a separation distance D3 smaller than the air insulation distance in the lateral portion 10a covered by the insulating resin 13, thereby reducing the distance between the second bus bar 12 and the main circuit substrate 5. As a result, the distance D4 between the main circuit substrate 5 and the power substrate 6 arranged so as to sandwich the first bus bar 11 and the second bus bar 12 can be reduced (see Figure 5 ), so it is possible to suppress the increase in the size in the up-down direction (Z direction) on the main circuit substrate 5.

[0066] In addition, in the present embodiment, as described above, the first bus bar 11 includes: the connection portion 11b that is exposed from the insulating resin 13 and connected to the main circuit substrate 5; and the connection portion 11c that is exposed from the insulating resin 13 and connected to the power supply substrate 6. Thus, the first bus bar 11 whose outer surface is covered with the insulating resin 13 can be easily connected to the main circuit substrate 5 by using the connection portion 11b exposed from the insulating resin 13. In addition, the first bus bar 11 whose outer surface is covered with the insulating resin 13 can be easily connected to the power supply substrate 6 by using the connection portion 11c exposed from the insulating resin 13.

[0067] In addition, in the present embodiment, as described above, the first bus bar 11 is configured to have a stepped shape bent toward the main circuit substrate 5 side (Z2 direction side), and the connecting portion 11b is connected to the main circuit substrate 5 from the upper side of the main circuit substrate 5. Furthermore, the connecting portion 11c of the first bus bar 11 is configured to have a stepped shape bent toward the power substrate 6 side (Z1 direction side), and is connected to the power substrate 6 from the lower side of the power substrate 6. Thus, even when the lateral portion 10a of the first bus bar 11 covered with the insulating resin 13 is separated from the main circuit substrate 5 by an amount corresponding to the air insulation distance, the connecting portion 11b of the first bus bar 11 can be brought close to the main circuit substrate 5 side (Z2 direction side) (the height position is brought close) by the stepped shape of the first bus bar 11 bent toward the main circuit substrate 5 side. As a result, the connecting portion 11b of the first bus bar 11 can be easily connected to the main circuit substrate 5. Furthermore, even when the lateral portion 10a of the first bus bar 11 covered with the insulating resin 13 is separated from the power board 6 by an amount corresponding to the air insulation distance, the connecting portion 11c can be brought closer to the power board 6 side (Z1 direction side) (the height position can be brought closer) by the step shape of the connecting portion 11c bent toward the power board 6 side. As a result, the connecting portion 11c of the first bus bar 11 can be easily connected to the power board 6.

[0068] In addition, in the present embodiment, as described above, the second bus bar 12 has the connection portion 12b exposed from the insulating resin 13 and connected to the main circuit substrate 5. Furthermore, the first bus bar 11 is arranged above the second bus bar 12 (Z1 direction side) in the lateral portion 10a of the resin-molded bus bar 10, and when viewed from above, the first bus bar 11 is formed in a circuitous manner so as not to overlap with the connection portion 12b of the second bus bar 12. Thus, in the lateral portion 10a of the resin-molded bus bar 10, even when the first bus bar 11 is arranged above the second bus bar 12, the connection portion 12b of the second bus bar 12 can be easily screwed (fastened) to the main circuit substrate 5 from above.

[0069] In addition, in the present embodiment, as described above, the vertical portion 10b of the resin molded bus bar 10 is configured such that the thickness in the direction (X direction) in which the first bus bar 11 and the second bus bar 12 overlap each other decreases as it goes upward (Z1 direction side) from the lateral portion 10a side. Thus, when manufacturing the resin molded bus bar 10, the resin molded bus bar 10 after resin molding can be easily removed from the molding die.

[0070] [Modifications]

[0071] The embodiments of the present application are to be considered as illustrative and non-limiting in all respects. The scope of the present invention is indicated not by the description of the above embodiments but by the claims, and includes all modifications (variations) within the meaning and scope equivalent to the claims.

[0072] For example, in the above embodiment, the first bus bar 11 and the second bus bar 12 are connected to the terminal block 4 and to the connection terminal 51 of the main circuit substrate 5, and are electrically connected to the semiconductor component 50 via the connection terminal 51 of the main circuit substrate 5, but the present invention is not limited to this. For example, the first bus bar and the second bus bar may be connected to the terminal block, and connected to the terminal portion of the semiconductor component for power conversion without passing through the main circuit substrate (the connection terminal of the main circuit substrate).

[0073] In the above embodiment, the resin-molded bus bar 10 is shown as an example in which the first bus bar 11 and the second bus bar 12 (two bus bars) are integrally molded by resin insulating the first bus bar 11 and the second bus bar 12 (two bus bars) by using the insulating resin 13, but the present invention is not limited to this. In the present invention, the resin-molded bus bar may be formed by integrally molding three or more bus bars by resin.

[0074] In addition, in the above-mentioned embodiment, for the resin-molded busbar 10, an example is shown in which the first busbar 11 connected to the positive terminal 41a of the DC terminal block 41 and the second busbar 12 connected to the negative terminal 41b of the DC terminal block 41 are integrally resin-molded, but the present invention is not limited to this. In the present invention, for the resin-molded busbar, any multiple busbars among the busbars connected to the DC terminal block, the busbars connected to the input terminal block, and the busbars connected to the output terminal block may be integrally molded, or these busbars may be combined and integrally molded. That is, the first busbar may also be any busbar among the busbars connected to the DC terminal block, the busbars connected to the input terminal block, and the busbars connected to the output terminal block. In addition, the second busbar may also be any busbar among the busbars connected to the DC terminal block, the busbars connected to the input terminal block, and the busbars connected to the output terminal block.

[0075] In addition, in the above embodiment, an example is shown in which the lateral portion 10a of the resin-molded bus bar 10 is arranged between the main circuit substrate 5 and the power substrate 6, but the present invention is not limited to this. In the present invention, the power substrate may be arranged in a staggered manner in the direction (X direction or Y direction) along the main circuit substrate so as not to cover the upper part of the lateral portion of the resin-molded bus bar.

[0076] In addition, in the above-mentioned embodiment, an example is shown in which the first bus bar 11 has a connection portion 11b (first main circuit substrate connection portion) exposed from the insulating resin 13 and connected to the main circuit substrate 5 and a connection portion 11c (power substrate connection portion) exposed from the insulating resin 13 and connected to the power substrate 6, but the present invention is not limited to this. In the present invention, a bus bar connected to the positive terminal of the DC terminal block and connected to the power substrate may be provided independently of the resin-molded first bus bar.

[0077] In addition, in the above-mentioned embodiment, an example is shown in which the first bus bar 11 is configured to have a stepped shape bent toward the main circuit substrate 5 side (Z2 direction side) and the connection portion 11b (first main circuit substrate connection portion) is connected to the main circuit substrate 5 from above the main circuit substrate 5, but the present invention is not limited thereto. In the present invention, it is also possible to configure that the connection terminal provided on the main circuit substrate is formed in a manner extending toward the first main circuit substrate connection portion side of the first bus bar, and the first main circuit substrate connection portion of the first bus bar is not bent toward the main circuit substrate side, but the first main circuit substrate connection portion of the first bus bar is connected using the connection terminal provided on the main circuit substrate.

[0078] In addition, in the above-mentioned embodiment, an example is shown in which the connection portion 11c (power substrate connection portion) of the first bus bar 11 is configured to have a stepped shape bent toward the power substrate 6 side (Z1 direction side) and connected to the power substrate 6 from the bottom of the power substrate 6, but the present invention is not limited to this. In the present invention, it is also possible to configure that the connection terminal provided on the power substrate is formed in a manner extending toward the power substrate connection portion side of the first bus bar, and the power substrate connection portion of the first bus bar is not bent toward the power substrate side, but the power substrate connection portion of the first bus bar is connected using the connection terminal provided on the power substrate.

[0079] In addition, in the above embodiment, an example is shown in which the first bus bar 11 is arranged above (in the Z1 direction) the second bus bar 12 in the lateral portion 10a of the resin-molded bus bar 10, but the present invention is not limited thereto. In the present invention, the first bus bar may be arranged below the second bus bar in the lateral portion of the resin-molded bus bar.

[0080] In addition, in the above-mentioned embodiment, an example is shown in which the first bus bar 11 connected to the positive terminal 41a of the DC terminal block 41 is arranged above (in the Z1 direction) the second bus bar 12 connected to the negative terminal 41b of the DC terminal block 41 in the lateral portion 10a of the resin-molded bus bar 10, but the present invention is not limited to this. In the present invention, the bus bar connected to the positive terminal of the DC terminal block may be arranged below the bus bar connected to the negative terminal of the DC terminal block in the lateral portion of the resin-molded bus bar.

[0081] In the above embodiment, the first bus bar 11 is covered with the insulating resin 13 up to the vicinity of the connection terminal 51 (see FIG. Figure 5 ), but the present invention is not limited to this. In the present invention, the resin-molded bus bar may be configured such that the first bus bar is exposed from the insulating resin in a portion where a distance corresponding to the air insulation distance can be ensured (can be separated) between the first bus bar and the power substrate. That is, the resin-molded bus bar may be configured such that the first bus bar is covered with the insulating resin only in a portion where a distance corresponding to the air insulation distance cannot be ensured (cannot be separated) between the first bus bar and the power substrate. In addition, the resin-molded bus bar may be configured such that the second bus bar is exposed from the insulating resin in a portion where a distance corresponding to the air insulation distance can be ensured between the second bus bar and the main circuit substrate.

[0082] In the above embodiment, the first bus bar 11 is configured to have a step shape bent toward the main circuit substrate 5 side (Z2 direction side) in the portion covered by the insulating resin 13, and the connecting portion 11b (first main circuit substrate connecting portion) exposed from the insulating resin 13 is connected to the main circuit substrate 5 from the upper side (Z1 direction side) of the main circuit substrate 5 (see FIG. Figure 5 ), but the present invention is not limited thereto. In the present invention, the step-shaped portion of the first bus bar bent toward the main circuit substrate side may be exposed from the insulating resin. Figure 6 As in the resin molded bus bar 210 of the modified example shown in FIG. 1 , the connection portion 211b (first main circuit board connection portion) exposed from the insulating resin 213 may have a connection portion 211b (first main circuit board connection portion) connected to the main circuit board 5 (see FIG. 1 ). Figure 5 ) side (Z2 direction side). Thus, even when the lateral portion 10a where the first bus bar 11 is covered with the insulating resin 213 is relative to the main circuit substrate 5 (refer to Figure 5 ) is separated by an amount corresponding to the air insulation distance, the step shape of the connection portion 211b bent toward the main circuit substrate 5 side (Z2 direction side) can be used to bring the connection portion 211b closer to the main circuit substrate 5 side (Z2 direction side) (make the height position closer). As a result, the connection portion 211b of the first bus bar 11 can be easily connected to the main circuit substrate 5.

Claims

1. A power conversion device, wherein: The power conversion device has: A main circuit substrate equipped with semiconductor components for power conversion; a terminal block disposed above the main circuit substrate and connected to wiring from outside the device; and a resin-molded bus bar, wherein a plate-shaped first bus bar and a plate-shaped second bus bar are integrally resin-molded in such a manner that they are insulated by an insulating resin, the first bus bar and the second bus bar being connected to the terminal block and electrically connected to the main circuit substrate or the semiconductor component for power conversion, The resin molded bus bar is formed in an L-shaped shape having a lateral portion extending along the main circuit substrate and a vertical portion extending upward from the lateral portion toward the terminal block. The power conversion device further includes a power supply substrate, which is arranged above the main circuit substrate and carries electronic components for generating a control power supply. The resin molded bus bar is formed so that the outer surface of the first bus bar and the outer surface of the second bus bar are covered with the insulating resin. The first bus bar is arranged between the main circuit substrate and the power substrate in a state where the first bus bar is separated from the power substrate by a second separation distance smaller than an air insulation distance in the lateral portion covered by the insulating resin. The second bus bar is arranged between the main circuit substrate and the power supply substrate in a state where the second bus bar is separated from the main circuit substrate by a third separation distance smaller than an air insulation distance in the lateral portion covered by the insulating resin. The first bus bar is electrically connected to the main circuit substrate by a screw, is electrically connected to the power substrate by another screw, and is electrically connected to the semiconductor component via a connecting terminal. The second bus bar is electrically connected to the main circuit substrate by another screw, and is electrically connected to the semiconductor component via another connecting terminal.

2. The power conversion device according to claim 1, wherein: The resin molded bus bar is configured such that the insulating resin is interposed between the first bus bar and the second bus bar, and the first bus bar and the second bus bar are stacked in a state of being separated from each other by a first separation distance that is smaller than an air insulation distance.

3. The power conversion device according to claim 2, wherein: The terminal block includes a DC terminal block, The first bus bar has a positive electrode connecting portion, the positive electrode connecting portion being exposed from the insulating resin and connected to a positive electrode terminal of the DC terminal block. The second bus bar has a negative electrode connecting portion, the negative electrode connecting portion being exposed from the insulating resin and connected to a negative electrode terminal of the DC terminal block. The first bus bar and the second bus bar are configured so that currents flow in directions opposite to each other.

4. The power conversion device according to claim 1, wherein: The first bus bar has: a first main circuit substrate connecting portion exposed from the insulating resin and connected to the main circuit substrate; and A power substrate connecting portion is exposed from the insulating resin and connected to the power substrate.

5. The power conversion device according to claim 4, wherein: The first bus bar is configured to have a stepped shape bent toward the main circuit substrate, and the first main circuit substrate connecting portion is connected to the main circuit substrate from above the main circuit substrate. The power board connecting portion of the first bus bar is configured to have a stepped shape bent toward the power board, and is connected to the power board from below the power board.

6. The power conversion device according to any one of claims 1 to 5, wherein: The second bus bar has a second main circuit substrate connecting portion that is exposed from the insulating resin and connected to the main circuit substrate. The first bus bar is arranged above the second bus bar in the lateral portion of the resin molded bus bar, and is formed in a meandering manner so as not to overlap with the second main circuit board connecting portion of the second bus bar when viewed from above.

7. The power conversion device according to claim 1, wherein: The vertical portion of the resin molded bus bar is configured such that a thickness in a direction in which the first bus bar and the second bus bar overlap each other decreases as it goes upward from the lateral portion side.

Images