JP2021145104A - Power converter - Google Patents

Abstract

To reduce the size of a power converter while securing a creepage distance required between a plurality of bus bars.SOLUTION: A power converter (10) electrically connected between an on-vehicle power supply (2) and a rotary electric machine (5), contains: a plurality of bus bars (14 to 18); a semiconductor chip (11) electrically connected to the plurality of bus bars; and insulation parts (19, 19A, 19B, 19C, and 19D) that are insulation parts for sealing the plurality of bus bars and the semiconductor chip, in which a flat first surface region (191) vertical to a first direction is included on a first side (Z1) of a first direction (Z). The plurality of bus bars contains first bus bars (18, 18A, 18B, 18C, and 18D) and a second bus bar (15), which are close to each other to a first distance (Δ1) previously regulated, which is larger than 0 on the first side from a center of the first direction in a region overlapped to the first surface region in view of the first direction.SELECTED DRAWING: Figure 7

Description

The present disclosure relates to a power converter electrically connected between an in-vehicle power supply and a rotary electric machine.

In this type of power converter, a technique is known in which a semiconductor chip is bonded to a plurality of bus bars and the bus bar and the semiconductor chip are sealed with a resin insulating portion.

Japanese Unexamined Patent Publication No. 2001-308263

However, in the conventional technology as described above, since there are many exposed parts of a plurality of bus bars from the insulating part, the power converter (module) secures the creepage distance required for electrical insulation in the exposed part. It is difficult to reduce the size of the.

Therefore, on one aspect, the present disclosure aims to reduce the size of the power converter while ensuring the required creepage distance between the plurality of bus bars.

On one side, it is a power converter that is electrically connected between an in-vehicle power supply and a rotary electric machine.
With multiple busbars
A semiconductor chip electrically connected to the plurality of bus bars and
An insulating portion provided so as to cover a part of the plurality of bus bars and the semiconductor chip, and having a planar first surface region perpendicular to the first direction on the first side in the first direction. Including and
The plurality of bus bars are defined in advance to be larger than 0 on the first side of the insulating portion in the insulating portion in the first direction and in a region overlapping the first surface region when viewed in the first direction. A power converter is provided that includes a first busbar and a second busbar that are close to each other up to a distance.

On one side, according to the present invention, it is possible to reduce the size of the power converter while ensuring the required creepage distance between the plurality of bus bars.

It is a figure which shows an example of the whole structure of the motor drive system for electric vehicles. It is a perspective view of the inverter module from the Z1 side in the Z direction. It is a perspective view of the inverter module from the Z2 side in the Z direction. It is a perspective view of the inside of the inverter module (the state where the resin mold part is removed). It is a top view of the inside of the inverter module (the state where the resin mold part is removed). It is sectional drawing of the joint part between one chip, a negative electrode bus bar, and an output bus bar. It is an enlarged view of P1 part of FIG. 5A. It is explanatory drawing of an example of the mounting state of an inverter module. It is sectional drawing which follows the line A0-A0 of FIG. 2A. It is a similar cross-sectional view which shows schematic connection example of an output bus bar and an external bus bar. It is a perspective view of the inverter module by 1st comparative example. It is sectional drawing along the line A2-A2 of FIG. 9A. It is a perspective view of the inverter module by 2nd comparative example. It is sectional drawing along the line A3-A3 of FIG. 10A. It is sectional drawing which shows typically the inverter module by 1st modification. It is sectional drawing which shows typically the inverter module by 2nd modification. It is sectional drawing which shows typically the inverter module by 3rd modification. It is sectional drawing which shows typically the inverter module by 4th modification. It is sectional drawing which shows typically the inverter module by the 5th modification.

Hereinafter, each embodiment will be described in detail with reference to the accompanying drawings.

In the following, prior to the description of the power converter according to the present embodiment, first, the motor drive system 1 for an electric vehicle to which the power converter according to the present embodiment is preferably applied will be described. In the description of FIG. 1 relating to the motor drive system 1 for an electric vehicle, the term "connection" between various elements means "electrical connection" unless otherwise specified.

FIG. 1 is a diagram showing an example of the overall configuration of the motor drive system 1 for an electric vehicle. The motor drive system 1 is a system that drives a vehicle by driving a traveling motor 5 (an example of a rotary electric machine) using the electric power of a high-voltage battery 2 (an example of an in-vehicle power supply). As long as the electric vehicle travels by driving the traveling motor 5 using electric power, the details of its method and configuration are arbitrary. The electric vehicle typically includes a hybrid vehicle whose power source is an engine and a traveling motor 5, and an electric vehicle whose power source is only a traveling motor 5. Hereinafter, the vehicle refers to a vehicle on which the motor drive system 1 is mounted, unless otherwise specified.

As shown in FIG. 1, the motor drive system 1 includes a high-pressure battery 2, a smoothing capacitor 3, an inverter 4, a traveling motor 5, and an inverter control device 6.

The high-voltage battery 2 is an arbitrary power storage device that stores electric power and outputs a DC voltage, and may include a capacitive element such as a nickel-metal hydride battery, a lithium-ion battery, or an electric double-layer capacitor. The high voltage battery 2 is typically a battery having a rated voltage of more than 100 V, for example, having a rated voltage of 288 V.

The inverter 4 includes U-phase, V-phase, and W-phase arms arranged in parallel with each other between the positive electrode line and the negative electrode line. The U-phase arm includes a series connection of switching elements (IGBT: Insulated Gate Bipolar Transistor) Q1 and Q2 in this example, and a V-phase arm includes a series connection of switching elements (IGBT) Q3 and Q4 in this example, and a W-phase arm. Includes a series connection of switching elements (IGBTs in this example) Q5, Q6. Further, diodes D11 to D16 are arranged between the collector and the emitter of each of the switching elements Q1 to Q6 so that a current flows from the emitter side to the collector side, respectively. Note that the switching elements Q1 to Q6 may be switching elements other than the IGBT, such as a MOSFET (methal index semiconductor field-effect transistor).

The traveling motor 5 is, for example, a three-phase AC motor, and one ends of three coils of U, V, and W phases are commonly connected at a neutral point. The other end of the U-phase coil is connected to the midpoint M1 of the switching elements Q1 and Q2, the other end of the V-phase coil is connected to the midpoint M2 of the switching elements Q3 and Q4, and the other end of the W-phase coil is. It is connected to the midpoint M3 of the switching elements Q5 and Q6. A smoothing capacitor 3 is connected between the collector of the switching element Q1 and the negative electrode line.

Various sensors such as a current sensor (not shown) that detects the current flowing through the traveling motor 5 are connected to the inverter control device 6. The inverter control device 6 controls the inverter 4 based on sensor information from various sensors. The inverter control device 6 includes, for example, a CPU, a ROM, a main memory (all not shown), and the various functions of the inverter control device 6 are such that a control program recorded in the ROM or the like is read into the main memory by the CPU. It is realized by being executed. The control method of the inverter 4 is arbitrary, but basically, the two switching elements Q1 and Q2 related to the U phase are turned on / off in opposite phases, and the two switching elements Q3 and Q4 related to the V phase are turned on and off. It turns on / off in opposite phase to each other, and the two switching elements Q5 and Q6 related to the W phase turn on / off in opposite phase to each other.

In the example shown in FIG. 1, the motor drive system 1 includes a single traveling motor 5, but may include an additional motor (including a generator). In this case, the additional motor (s) may be connected to the high pressure battery 2 together with the corresponding inverter in parallel with the traveling motor 5 and the inverter 4. Further, in the example shown in FIG. 1, the motor drive system 1 does not include a DC / DC converter, but a DC / DC converter may be provided between the high-voltage battery 2 and the inverter 4.

As shown in FIG. 1, a cutoff switch SW1 for cutting off the power supply from the high-voltage battery 2 is provided between the high-voltage battery 2 and the smoothing capacitor 3. The cutoff switch SW1 may be composed of a semiconductor switch, a relay, or the like. The shutoff switch SW1 is normally on, and is turned off when, for example, a vehicle collision is detected. The on / off switching of the cutoff switch SW1 may be realized by the inverter control device 6 or may be realized by another control device.

Next, with reference to FIGS. 2A to 6, a module configuration related to the inverter 4 (hereinafter, referred to as “inverter module 10”) will be outlined. In addition, in FIG. 2A and later, for the sake of legibility, there are cases where a reference reference numeral is only partially attached to a plurality of parts having the same attribute. Further, in the following description, the term "predetermined" is used to mean "predetermined".
2A and 2B are perspective views of the inverter module 10 (an example of a power converter) viewed from different directions, and FIG. 3 shows the inside of the inverter module 10 (with the resin mold portion 19 removed). It is a perspective view. FIG. 4 is a plan view of the inside of the inverter module 10 (with the resin mold portion 19 removed). In addition, in FIGS. 2A and 3 and the like, the X direction (an example of the third direction), the Y direction (an example of the second direction), and the Z direction (an example of the first direction), which are three directions orthogonal to each other, are shown. Sides related to each direction (for example, for the Z direction, the Z direction Z1 side and the Z direction Z2 side) are defined.

The inverter module 10 is a module related to the inverter 4. In this embodiment, as an example, the switching element Q1 (the same applies to the switching elements Q2 to Q6) is realized in the form of a chip having a diode D11 built-in, and is also referred to as "chip 11 (an example of a semiconductor chip)".

As shown in FIGS. 2A, 2B, and 3, the inverter module 10 includes a positive electrode bus bar 14 (an example of a third bus bar), a negative electrode bus bar 15 (an example of a second bus bar), and a plurality of output bus bars 16 and 17. , 18 (an example of a first bus bar) and flexible printed circuit boards (FPC: Flexible Printed Circuits) 91 and 92.

The positive electrode bus bar 14, the negative electrode bus bar 15, and the output bus bars 16, 17, and 18 (hereinafter, collectively referred to as simply “bus bars”) are formed by pressing or cutting a sheet metal member, respectively. The positive electrode bus bar 14 forms a positive electrode line from the positive electrode side of the high voltage battery 2, and the negative electrode bus bar 15 forms a negative electrode line. Further, the output bus bars 16, 17, and 18 electrically connect the inverter 4 and the traveling motor 5 (see FIG. 1).

In this embodiment, as an example, the main body 141 of the positive electrode bus bar 14 and the main body 151 of the negative electrode bus bar 15 extend in parallel and in the same direction, and the output bus bars 16, 17, and 18 are the main body 141 of the positive electrode bus bar 14. And extends so as to intersect the main body 151 of the negative electrode bus bar 15. The output bus bars 16, 17 and 18 face the positive electrode bus bar 14 in the Z direction from the Z1 side in the Z direction on one end side in the longitudinal direction, respectively. Three chips 11 related to the upper arm are provided between each of the output bus bars 16, 17, and 18 in the Z direction and the positive electrode bus bar 14. The three chips 11 related to the upper arm are joined along the surface to the surface of the positive electrode bus bar 14 on the Z direction Z1 side and the surface of one of the output bus bars 16, 17, 18 on the Z direction Z2 side. NS. Similarly, the output bus bars 16, 17, and 18 face the negative electrode bus bar 15 in the Z direction from the Z direction Z2 side on the other end side in the longitudinal direction, respectively. Three chips 11 related to the lower arm are provided between each of the output bus bars 16, 17, and 18 in the Z direction and the negative electrode bus bar 15. The three chips 11 related to the lower arm are joined along the surface to the surface of the negative electrode bus bar 15 on the Z direction Z2 side and the surface of one of the output bus bars 16, 17, 18 on the Z direction Z1 side. NS. Further details of the bus bar configuration will be described later.

The flexible printed circuit boards 91 and 92 realize the control wiring 13 (see FIG. 6) that electrically connects each chip 11 and the control board 40. The flexible printed circuit board 91 is provided for each of the three chips 11 (that is, the three chips 11 related to the lower arm) on the negative electrode bus bar 15. The flexible printed circuit board 92 is provided for each of the three chips 11 (that is, the three chips 11 related to the upper arm) on the positive electrode bus bar 14.

The chips 11, the positive electrode bus bar 14, the negative electrode bus bar 15, and the output bus bars 16, 17, and 18 related to the switching elements Q1 to Q6 are at least partially formed in the resin mold portion 19 as shown in FIGS. 2A and 2B. It may be integrated in a state of being embedded in. The resin mold portion 19 is formed, for example, by casting a molten resin material and curing it.
From the resin mold portion 19, the flexible printed circuit boards 91 and 92 and the connection terminal portions of the positive electrode bus bar 14, the negative electrode bus bar 15, and the output bus bars 16, 17, and 18, respectively, are projected. In the examples shown in FIGS. 2A and 2B, the flexible printed circuit board 91 and the flexible printed circuit board 92 extend outward from the resin mold portion 19 in a manner of being pulled out from the side surfaces opposite to each other of the inverter module 10.

FIG. 5A is a cross-sectional view of a joint portion between one chip 11, the negative electrode bus bar 15, and the output bus bar 18, and shows a part of the cross section along the lines A1-A1 of FIG. FIG. 5B is an enlarged view of the P1 portion of FIG. 5A. As a representative, the configuration relating to the joining between one chip 11, the negative electrode bus bar 15, and the output bus bar 18 will be described, but the same may apply to the other chips 11. In FIG. 5A, the resin mold portion 19 is not shown.

As shown in FIGS. 5A and 5B, the negative electrode bus bar 15 and the output bus bar 18 are respectively bonded to the chip 11 via a bonding material (shown by the bonding layer 90). The bonding material may be any conductive material, and may be, for example, a bonding material containing silver nanoparticles.

FIG. 6 is an explanatory diagram of an example of the mounting state of the inverter module 10. Note that FIG. 6 is a schematic view, in which other elements (capacitor case 30, etc.) are separated in the Z direction in relation to the inverter module 10.

For example, as shown in FIG. 6, the inverter module 10 may be supported on the Z1 side of the capacitor case 30 in the Z direction. The capacitor case 30 houses the capacitor module 20. The capacitor module 20 has a plurality of capacitor elements constituting the smoothing capacitor 3. The capacitor case 30 may be made of, for example, a material having high thermal conductivity (for example, copper or aluminum). The condenser case 30 may integrally include a flow path forming portion 38 (an example of a cooling device) that forms a refrigerant flow path. The flow path forming portion 38 is formed on the Z1 side of the capacitor case 30 in the Z direction. In this case, the inverter module 10 can be effectively cooled by supporting (contacting) the inverter module 10 on the surface 38A of the flow path forming portion 38 on the Z1 side in the Z direction. That is, the surface of the inverter module 10 on the Z2 side in the Z direction forms a boundary surface 190 when thermally connected to the flow path forming portion 38. However, in the modified example, the flow path forming portion 38 may be formed separately from the capacitor case 30 and may be arranged in the capacitor case 30.

In the example shown in FIG. 6, the inverter module 10 may be configured as a unit integrated with the capacitor module 20 (the module related to the smoothing capacitor 3) and the capacitor case 30.

As shown in FIG. 6, for example, the control board 40 may be arranged on the Z1 side of the inverter module 10 in the Z direction via the shield plate 50. The control board 40 may realize the inverter control device 6. The inverter module 10 may be electrically connected to the connector 42 on the control board 40 via the control wiring 13. That is, the control wiring 13 electrically connects each chip 11 and the inverter control device 6. The control wiring 13 is wiring for transmitting control signals (gate drive signals) of switching elements Q1 to Q6, sensor information, and the like. In this embodiment, as an example, the control wiring 13 is realized by the wiring on the flexible printed circuit boards 91 and 92 as described above, but is realized by a control terminal (for example, an L-shaped terminal) or the like. May be good.

Next, the details of the bus bar will be described with reference to FIGS. 7 and 7 while continuing to refer to FIGS. 2A, 2B, and 3.

FIG. 7 is an explanatory view of the relationship between the negative electrode bus bar 15 and the output bus bar 18 and the resin mold portion 19 in the inverter module 10, and is a cross-sectional view taken along the lines A0-A0 of FIG. 2A. FIG. 8 is a similar cross-sectional view schematically showing a connection example of the output bus bar 18 and the external bus bar 80. Note that FIG. 7 (the same applies to the same cross-sectional views thereafter) is an explanatory view, and the configuration of each part is shown more schematicly than the cross-sectional view shown in FIG. 5A. For example, in FIG. 7, the bonding layer 90 is not shown. Here, the relationship between the negative electrode bus bar 15 and the output bus bar 18 and the resin mold portion 19 will be described, but the same applies to the relationship between the negative electrode bus bar 15 and the output bus bars 16 and 17 and the resin mold portion 19.

The positive electrode bus bar 14 includes a main body portion 141 extending linearly over the three chips 11 related to the upper arm, and end portions 142 on both sides of the main body portion 141. The main body 141 extends in the XY plane. In the example shown in FIG. 3, the end portions 142 on both sides in the X direction are bent from the main body portion 141 to the Z1 side in the Z direction by approximately 90 degrees and extend toward the Z1 side in the Z direction, and the end faces on the Z1 side in the Z direction are formed. , Exposed from the resin mold portion 19 (an example of the insulating portion). The surface of the end portion 142 on the Z direction Z1 side is flush with the surface of the resin mold portion 19 on the Z direction Z1 side.

The negative electrode bus bar 15 includes a main body portion 151 extending linearly over the three chips 11 related to the lower arm, and end portions 152 on both sides of the main body portion 151. The main body 151 extends in the XY plane. In the example shown in FIG. 3, the end portions 152 on both sides in the X direction are bent from the main body portion 151 to the Z2 side in the Z direction by approximately 90 degrees and extend toward the Z2 side in the Z direction, and the end faces on the Z2 side in the Z direction are formed. It is exposed from the resin mold portion 19. The surface of the end portion 152 on the Z-direction Z2 side is flush with the surface of the resin mold portion 19 on the Z-direction Z2 side. However, in the modified example, the end portion 152 of the negative electrode bus bar 15 is bent from the main body portion 151 to the Z1 side in the Z direction by approximately 90 degrees and extends toward the Z1 side in the Z direction, and the end surface on the Z1 side in the Z direction is the resin mold portion. It may be exposed from 19.

The main body 141 of the positive electrode bus bar 14 and the main body 151 of the negative electrode bus bar 15 are arranged in the Y direction and extend in the X direction in parallel with each other. However, the main body 141 of the positive electrode bus bar 14 and the main body 151 of the negative electrode bus bar 15 are offset in the Z direction, and specifically, the main body 141 of the positive electrode bus bar 14 is Z with respect to the main body 151 of the negative electrode bus bar 15. It is offset to the direction Z2 side. This offset amount corresponds to the dimension corresponding to the mounting space of the chip 11 in the Z direction (see d3 in FIG. 7).

The surface of the main body 141 of the positive electrode bus bar 14 on the side not joined to the chip 11 (Z2 side in the Z direction) is exposed from the surface of the resin mold portion 19 on the Z2 side in the Z direction. The surface of the main body portion 141 of the positive electrode bus bar 14 on the Z-direction Z2 side is flush with the surface of the resin mold portion 19 on the Z-direction Z2 side (in the same plane).

The surface of the main body 151 of the negative electrode bus bar 15 on the side not bonded to the chip 11 (Z1 side in the Z direction) is not exposed from the surface of the resin mold portion 19 on the Z1 side in the Z direction. That is, the surface of the main body portion 151 of the negative electrode bus bar 15 on the Z1 side in the Z direction is offset to the surface on the Z1 side in the Z direction of the resin mold portion 19 by a predetermined dimension d0 on the Z2 side in the Z direction (see FIG. 7). .. In other words, the main body portion 151 of the negative electrode bus bar 15 is covered with the surface layer of the resin mold portion 19 on the Z1 side in the Z direction. In this case, the thickness of the surface layer of the resin mold portion 19 on the Z direction Z1 side corresponds to the predetermined dimension d0 when measured from the surface of the main body portion 151 of the negative electrode bus bar 15 on the Z direction Z1 side. The surface layer of the resin mold portion 19 on the Z direction Z1 side covers the surface of the main body portion 151 of the negative electrode bus bar 15 on the Z direction Z1 side, so that another bus bar with respect to the negative electrode bus bar 15 (Z1 side of the resin mold portion 19 in the Z direction) It is a bus bar exposed from the above, and in this example, it functions to enhance the electrical insulation of the positive electrode bus bar 14 and the output bus bars 16, 17, 18). Therefore, the thickness of the surface layer of the resin mold portion 19 on the Z1 side in the Z direction (that is, the predetermined dimension d0) is preferably the minimum thickness so that such a function can be appropriately exhibited, for example, about 1 mm. good.

The output bus bars 16, 17, and 18 include main body portions 161 and 171 and 181 extending in the Y direction, first end portions 162, 172 and 182, and second end portions 163, 173 and 183, respectively.

The main body portions 161 and 171 and 181 are parallel to each other and are arranged at equal intervals in the X direction and extend in the Y direction. As shown in FIG. 3, the main body portions 161 and 171 are offset in the Z direction near an intermediate position in the Y direction (between the main body portion 151 and the main body portion 141) while extending in the XY plane. Specifically, the main body portions 161, 171 and 181 extend to the Z direction Z2 side from the main body portion 151 on the Y direction Y1 side, and extend to the Z direction Z1 side from the main body portion 141 on the Y direction Y2 side. It is postponed.

The first end portions 162, 172, and 182 project toward the Z direction Z2 side of the main body portions 161 and 171 and 181 on the Y direction Y2 side, respectively. The end faces of the first end portions 162, 172, and 182 on the Z-direction Z2 side are exposed from the surface of the resin mold portion 19 on the Z-direction Z2 side, respectively. The end faces of the first end portions 162, 172, and 182 on the Z-direction Z2 side are flush with the surface of the resin mold portion 19 on the Z-direction Z2 side (in the same plane).

The second end portions 163, 173, and 183 project to the Y direction Y2 side of the main body portions 161, 171 and 181, respectively, and to the Z direction Z1 side. The second end portions 163, 173, and 183 form terminal portions for electrical connection with the traveling motor 5 in the inverter module 10. The end faces of the second end portions 163, 173, and 183 on the Z direction Z1 side are exposed from the surface of the resin mold portion 19 on the Z direction Z1 side, and are welded to an external bus bar (see the external bus bar 80 in FIG. 8). Joined by. Note that FIG. 8 schematically shows a state in which the second end portion 183 of the output bus bar 18 is joined to the external bus bar 80 by the welded portion 84. In this case, the welded portion 84 may be realized by laser welding or the like. The end faces of the second end portions 163, 173, and 183 on the Z direction Z1 side are flush with the surface of the resin mold portion 19 on the Z direction Z1 side (in the same plane). That is, the height of the second end portions 163, 173, 183 from the main body portions 161, 171 and 181 has a predetermined dimension d0. Thereby, it is possible to prevent the dimension of the inverter module 10 in the Z direction from being significantly increased due to the second end portions 163, 173, and 183. However, in the modified example, the end faces of the second end portions 163, 173, and 183 on the Z direction Z1 side may be located on the Z direction Z1 side of the surface of the resin mold portion 19 on the Z direction Z1 side, respectively.

The second end portions 163, 173, and 183 have Zs of the first end portions 162, 172, and 182 in order to secure a relatively large joint area with the external bus bar (see the external bus bar 80 in FIG. 8). It may be configured to have an end face on the Z1 side that is larger than the end face on the direction Z2 side.

In this embodiment, the first end portion 162 (the same applies to the first end portions 172 and 182) and the second end portion 163 (the same applies to the second end portions 173 and 183) are formed at the same position in the Y direction. Therefore, the dimension of the output bus bar 16 in the Y direction can be reduced as compared with the case where the output bus bar 16 is formed at different positions. A part or all of the first end portion 162 and / or the second end portion 163 may be formed by joining another member to the main body portion 161 formed by pressing with sheet metal.

Here, in the present embodiment, as an example, the positive electrode bus bar 14, the negative electrode bus bar 15, and the output bus bars 16, 17, and 18 have main bodies 141, 151, 161, 171 and 181 having the same plate thickness, respectively. do. Further, in this embodiment, as an example, it is assumed that the six chips 11 are arranged at the same position in the Z direction. In this case, the surface portion of the main body portion 151 on the Z direction Z1 side and the surface portion of the main body portions 161, 171 and 181 on the Z direction Z1 side on the Y direction Y2 side (the surface facing the main body portion 141 in the Z direction). The portion) is flush with each other (in the same XY plane), and is the Y direction of the surface of the main body 141 on the Z direction Z2 side and the surface of the main body 161, 171 and 181 on the Z direction Z2 side. The surface portion on the Y1 side (the surface portion facing the main body portion 151 in the Z direction) is flush with each other (in the same XY plane). Therefore, according to such a configuration, the extension range of the main body portions 141, 151, 161, 171 and 181 in the Z direction can be minimized. That is, assuming that the thickness (maximum thickness) of the main bodies 141, 151, 161, 171 and 181 is d1 (see FIG. 7), the extension range of the main bodies 141, 151, 161 and 171 and 181 in the Z direction is d1. It becomes × 2 + d3 (see FIG. 7). Then, in the present embodiment, as described above, the resin mold portion 19 covers the surface layer on the Z direction Z1 side (thickness corresponds to the predetermined dimension d0) on the surface of the main body portion 151 on the Z direction Z1 side. Therefore, the dimension dr of the resin mold portion 19 in the Z direction is dr = d1 × 2 + d3 + d0 (see FIG. 7). As described above, the predetermined dimension d0 is significantly smaller than the thickness d1 of the bus bar (for example, about 1 mm), so that the thickness of the inverter module 10 does not become excessive due to the predetermined dimension d0.

As described above, in this embodiment, the resin mold portion 19 is a flat surface that overlaps the main body portions 141, 151, 161, 171 and 181 on the Z1 side (an example of the first side) in the Z direction when viewed in the Z direction. A planar shape having a region 191 (an example of a first surface region) and overlapping the main body portions 141, 151, 161, 171 and 181 in the Z direction on the Z2 side (an example of the second side). It has a surface region 192 (an example of a second surface region), and the surface region 191 and the surface region 192 are parallel to each other (in the XY plane perpendicular to the Z direction). The flat shape does not have to be strictly flat, and is a concept that allows fine irregularities and various dimensional errors that may occur due to sink marks of the resin or the like. For example, the surface region 191 and the surface region 192 may be formed by cutting or the like after resin molding. Further, in this embodiment, the surface region 191 forms the entire surface of the resin mold portion 19 on the Z direction Z1 side, and the surface region 192 forms the entire surface of the resin mold portion 19 on the Z direction Z2 side. .. However, in the modified example, a part of the surface of the resin mold portion 19 on the Z1 side in the Z direction and / or a part of the surface on the Z2 side in the Z direction may be formed in a convex or concave shape with respect to another region.

Further, in this embodiment, the positive electrode bus bar 14, the negative electrode bus bar 15, and the output bus bars 16, 17, and 18 have creepage distances (resin mold portions) in which the portions exposed from the resin mold portion 19 are larger than a predetermined value with respect to each other. It is separated by a distance (distance along the surface of 19). The predetermined value is a value equal to or more than the lower limit of the creepage distance to be secured, and is a value determined by design.

In particular, in this embodiment, in the region overlapping the surface region 192 when viewed in the Z direction, the negative electrode bus bar 15 and the output bus bars 16, 17, and 18 are centered in the Z direction (position of dr / 2) in the resin mold portion 19. It is covered with the resin mold portion 19 while being close to each other up to a predetermined distance Δ1 (see FIG. 7) (an example of the first distance) on the Z1 side in the Z direction. In FIG. 7, the negative electrode bus bar 15 and the output bus bar 18 show a state in which the main bodies (that is, the main bodies 151 and 181) are close to each other up to a predetermined distance Δ1 in the Y direction. In this case, the predetermined distance Δ1 is preferably smaller than the lower limit of the creepage distance to be secured along the surface of the resin mold portion 19. As a result, the distance between the negative electrode bus bar 15 and the output bus bars 16, 17, and 18 in the Y direction can be minimized, and the dimension of the inverter module 10 in the Y direction can be reduced.

On the other hand, the positive bus bars 14 and the output bus bars 16, 17, and 18 are located on the Z direction Z2 side of the resin mold portion 19 in the Z direction (position of dr / 2) and have predetermined distances Δ2 and Δ3 (see FIG. 7). It is exposed from the surface of the resin mold portion 19 on the Z2 side in the Z direction while being close to each other up to (an example of the second distance). In FIG. 7, the positive electrode bus bar 14 and the output bus bar 18 have main bodies (that is, main bodies 141 and 181) close to each other up to a predetermined distance Δ2 in the Y direction, and the main bodies 141 and the first end 182. However, a state in which the bus is close to a predetermined distance Δ3 in the Y direction is shown. In this case, the predetermined distances Δ2 and Δ3 are equal to or greater than the lower limit of the creepage distance to be secured along the surface of the resin mold portion 19. Therefore, in this embodiment, the predetermined distance Δ1 is preferably larger than the predetermined distances Δ2 and Δ3. The predetermined distances Δ2 and Δ3 may be the same or may be slightly different.

Further, in this embodiment, the positive electrode bus bar 14 and the output bus bars 16, 17, and 18 are flush with the surface of the resin mold portion 19 on the Z direction Z2 side of the resin mold portion 19 on the Z direction Z2 side. Since it is exposed, heat can be efficiently transferred from the positive electrode bus bar 14 and the output bus bars 16, 17, and 18 to the refrigerant (for example, long life coolant) in the flow path forming portion 38. As a result, the cooling performance of the bus bar by the flow path forming portion 38 and the cooling performance of the inverter module 10 can be effectively improved accordingly.

Further, in the present embodiment, the negative electrode bus bar 15 is also exposed on the Z-direction Z2 side of the resin mold portion 19 in such a manner that the end portion 152 is flush with the surface of the resin mold portion 19 on the Z-direction Z2 side. The cooling performance of the bus bar by the flow path forming portion 38 and the cooling performance of the inverter module 10 can be further effectively improved accordingly.

Next, the effects of this embodiment will be further described in comparison with the comparative examples shown in FIGS. 9A to 10B. In the comparative examples shown in FIGS. 9A to 10B, the same reference numerals may be attached to the components which may be the same as those in the present embodiment.

9A and 9B are explanatory views of the first comparative example, FIG. 9A is a perspective view of the inverter module 10', and FIG. 9B is a cross-sectional view taken along the lines A2-A2 of FIG. 9A.

In the first comparative example, instead of the flexible printed circuit boards 91 and 92, L-shaped control terminals 91'and 92'are used for wiring from the chip 11. As shown in FIG. 9A, one end side (the side electrically connected to the control substrate 40) of the L-shaped control terminals 91'and 92'is exposed from the surface of the resin mold portion 19'on the Z1 side in the Z direction. The other end side (the side electrically connected to the chip 11) is sealed in the resin mold portion 19'.

In such a first comparative example, since the L-shaped control terminals 91'and 92'are exposed from the surface of the resin mold portion 19'on the Z direction Z1 side, the surface of the resin mold portion 19'on the Z direction Z1 side. Cannot be processed into a flat surface (for example, cutting), or the workability deteriorates. Therefore, as schematically shown in FIG. 9B, relatively large irregularities tend to remain on the surface of the resin mold portion 19'on the Z1 side in the Z direction.

By the way, in this embodiment, as described above, the inverter module 10 is joined to the surface of the flow path forming portion 38 on the Z direction Z1 side, but when the inverter module 10 is assembled, the inverter module 10 is moved to the Z direction Z2 side. Is pressed by a jig (not shown) or the like. Such pressing is useful for increasing the reliability of the joint between the inverter module 10 and the flow path forming portion 38 and reducing the thermal resistance between the inverter module 10 and the flow path forming portion 38. Become.

In this regard, according to the first comparative example, since the L-shaped control terminals 91'and 92'are exposed from the surface of the resin mold portion 19'on the Z direction Z1 side, the resin mold portion 19'is exposed on the Z direction Z1 side. It is difficult to uniformly press the entire surface of the resin with a jig. As a result, in the first comparative example, the thermal resistance between the inverter module 10'and the flow path forming portion 38 tends to be relatively large.

On the other hand, according to the present embodiment, as described above, the flexible printed circuit boards 91 and 92 have side surfaces (side surfaces on the Y1 side and Y2 side in the Y direction) of the resin mold portion 19 other than the surface on the Z1 side in the Z direction. Since it is exposed from the above, the inconvenience that occurs in the first comparative example described above can be prevented. That is, the entire surface of the resin mold portion 19 on the Z1 side in the Z direction can be uniformly pressed by the jig. In particular, according to the present embodiment, as described above, the surface of the resin mold portion 19 on the Z direction Z1 side is flat over the entire surface, so that the entire surface of the resin mold portion 19 on the Z direction Z1 side is used as a jig. Therefore, it is possible to press more uniformly. As a result, according to this embodiment, it is possible to minimize the thermal resistance between the inverter module 10 and the flow path forming portion 38. It should be noted that such an effect can also be obtained by wiring means other than the flexible printed circuit boards 91 and 92. That is, in this embodiment, the L-shaped control terminal may be exposed from the side surface (the side surface on the Y1 side and the Y2 side in the Y direction) of the resin mold portion 19 other than the surface on the Z1 side in the Z direction.

10A and 10B are explanatory views of the second comparative example, FIG. 10A is a perspective view of the inverter module 10 ", and FIG. 10B is a cross-sectional view taken along the lines A3-A3 of FIG. 10A.

In the second comparative example, as shown in FIGS. 10A and 10B, the output bus bars 16 ", 17", 18 "(the main body portions) and the negative electrode bus bar 15" (the main body portion) are the resin mold portions 19 ". In this case, the output bus bars 16 ", 17", 18 "and the negative electrode bus bar 15" are the required creepage distances on the surface of the resin mold portion 19 "on the Z direction Z1 side. Therefore, the separation distance Δ1 ”in the Y direction (see FIG. 10B) tends to be relatively large. That is, the electricity between the output bus bars 16 ″, 17 ″, 18 ″ and the negative electrode bus bar 15 ″. The separation distance Δ1 ”in the Y direction needs to be set to be equal to or greater than the required creepage distance in order to ensure the appropriate insulation. As a result, in the second comparative example, the dimension of the inverter module 10 "in the Y direction tends to be large.

On the other hand, according to the present embodiment, as described above, the main body portions 161, 171, 181 of the output bus bars 16, 17 and 18, respectively, and the main body portion 151 of the negative electrode bus bar 15 are formed of the resin mold portion 19. It is not exposed from the surface on the Z1 side in the Z direction. Therefore, the predetermined distance Δ1 can be minimized in a manner smaller than the required creepage distance. As a result, the dimension of the inverter module 10 in the Y direction can be minimized.

Next, with reference to FIGS. 11 and 11 onward, various modifications that can be realized with respect to the above-described embodiment will be described.

Hereinafter, the changes relating to the output bus bar 18 will be described, but the output bus bars 16 and 17 are also changed in the same manner. Further, with respect to each of the following modifications, components that may be the same as those in the above-described embodiment may be designated by the same reference numerals and description thereof may be omitted.

FIG. 11 is a cross-sectional view schematically showing the inverter module 10A according to the first modification. FIG. 11 is a cross-sectional view along a cut surface corresponding to the cross-sectional view shown in FIG. 7.

The inverter module 10A according to the first modification differs from the above-mentioned inverter module 10 in that the output bus bar 18 is replaced by the output bus bar 18A, and the resin mold portion 19 is replaced by the resin mold portion 19A accordingly. The point is different.

The output bus bar 18A is mainly different from the output bus bar 18 according to the above-described embodiment in that the first end portion 182 is omitted. Specifically, the output bus bar 18A includes a main body portion 181A and a second end portion 183A.

The main body 181A differs from the main body 181 of the output bus bar 18 according to the above-described embodiment only in that the length in the Y direction is short. That is, the main body 181A terminates on the Y2 side in the Y direction near the edge of the main body 141 of the positive electrode bus bar 14 on the Y2 side in the Y direction. Along with this, the second end portion 183A is provided in a region overlapping the main body portion 141 of the positive electrode bus bar 14 when viewed in the Z direction.

Even with such a first modification, the same effect as that of the above-described embodiment can be obtained. In particular, according to the first modification, by shortening the length of the output bus bar 18A in the Y direction, the resin mold portion 19A can be made smaller in the Y direction than the resin mold portion 19 according to the above-described embodiment. As a result, the dimension of the inverter module 10A in the Y direction can be further minimized.
Further, according to the first modification, the output bus bar 18A can be formed to have a constant plate thickness. Therefore, the output bus bar 18A can be manufactured by pressing the sheet metal, and the manufacturability is improved.

FIG. 12 is a cross-sectional view schematically showing the inverter module 10B according to the second modification. FIG. 12 is a cross-sectional view along a cut surface corresponding to the cross-sectional view shown in FIG. 7. Note that FIG. 12 also shows the external bus bar 80 and the welded portion 84.

The inverter module 10B according to the second modification differs from the above-mentioned inverter module 10 in that the output bus bar 18 is replaced by the output bus bar 18B, and the resin mold portion 19 is replaced by the resin mold portion 19B accordingly. The point is different.

The output bus bar 18B is mainly different from the output bus bar 18 according to the above-described embodiment in that the second end portion 183 is replaced with the second end portion 183B. Specifically, the output bus bar 18B includes a main body portion 181, a first end portion 182, and a second end portion 183B.

The second end portion 183B is formed on the Y2 side in the Y direction of the first end portion 182. In this case, the second end portion 183B is a portion having an L-shaped cross section extending in the Y direction Y2 side of the first end portion 182, and the end face on the Z direction Z1 side is exposed from the resin mold portion 19B. The end surface of the second end portion 183B on the Z1 side in the Z direction may be flush with the surface of the resin mold portion 19B on the Z1 side in the Z direction.

In the second modification, as shown in FIG. 12, the end face of the second end portion 183B on the Z1 side in the Z direction is joined to the external bus bar 80. FIG. 12 schematically shows a welded portion 84 between the second end portion 183B and the external bus bar 80.

The resin mold portion 19B only has a change (change regarding dimensions in the Y direction, etc.) from the output bus bar 18 to the output bus bar 18B with respect to the resin mold portion 19 of the inverter module 10 described above. Is the same.

Even with such a second modification, the same effect as that of the above-described embodiment can be obtained. In particular, according to the second modification, since the second end portion 183B is provided on the Y2 side in the Y direction with respect to the first end portion 182, the above-described embodiment (the second end portion 183 is the first when viewed in the Z direction). The output bus bar 18B can be formed to have a constant plate thickness, unlike the configuration (which overlaps with the end portion 182). Therefore, the output bus bar 18B can be manufactured by pressing the sheet metal, and the manufacturability is improved.

FIG. 13 is a cross-sectional view schematically showing the inverter module 10C according to the third modification. FIG. 13 is a cross-sectional view along a cut surface corresponding to the cross-sectional view shown in FIG. 7. Note that FIG. 13 also shows the external bus bar 80 and the welded portion 84.

The inverter module 10C according to the third modification differs from the above-mentioned inverter module 10 in that the output bus bar 18 is replaced by the output bus bar 18C, and the resin mold portion 19 is replaced by the resin mold portion 19C accordingly. The point is different.

The output bus bar 18C is mainly different from the output bus bar 18 according to the above-described embodiment in that the second end portion 183 is replaced with the second end portion 183C. Specifically, the output bus bar 18C includes a main body portion 181, a first end portion 182, and a second end portion 183C.

The second end portion 183C is formed on the Y2 side of the first end portion 182 in the Y direction. In this case, the second end portion 183C is a portion extending on the Y2 side of the first end portion 182 in the Y direction, and is a portion in which two portions 1831 and 1832 having an L-shaped cross section are combined. That is, the second end portion 183C extends in the Y direction for a predetermined length in a manner continuous from the end portion of the first end portion 182 on the Z direction Z2 side, then bends in the Z direction Z1 side, and further. It extends in the Z direction toward the Z1 side in the Z direction, bends toward the Y2 side in the Y direction on the Z1 side in the Z direction, and then extends further in the Y direction for a predetermined length. The second end portion 183C is one of two portions having an L-shaped cross section (a portion extending a predetermined length in the Y direction on the Z1 side in the Z direction) 1832, and the surface on the Z1 side in the Z direction is made of resin. It is exposed from the mold portion 19C. The surface of the second end portion 183C on the Z direction Z1 side exposed from the resin mold portion 19C may be flush with the surface of the resin mold portion 19C on the Z direction Z1 side. Further, the second end portion 183C is a portion of two portions having an L-shaped cross section, and the other portion (a portion extending a predetermined length in the Y direction on the Z direction Z2 side) 1831 is a surface on the Z direction Z2 side. Is exposed from the resin mold portion 19C. The surface of the second end portion 183C on the Z-direction Z2 side exposed from the resin mold portion 19C may be flush with the surface of the resin mold portion 19C on the Z-direction Z2 side.

In the third modification, as shown in FIG. 13, the surface of the second end portion 183C is joined to the external bus bar 80 at the portion 1832 extending in the Y direction by a predetermined length on the Z direction Z1 side. Will be done. FIG. 13 schematically shows a welded portion 84 between the second end portion 183C and the external bus bar 80.

The resin mold portion 19C only has a change (change regarding dimensions in the Y direction, etc.) from the output bus bar 18 to the output bus bar 18C with respect to the resin mold portion 19 of the inverter module 10 described above. Is the same.

Even with such a third modification, the same effect as that of the above-described embodiment can be obtained. In particular, according to the third modification, since the second end portion 183C is provided on the Y2 side in the Y direction with respect to the first end portion 182, the above-described embodiment (the second end portion 183 is the first when viewed in the Z direction). The output bus bar 18C can be formed to have a constant plate thickness, unlike the configuration in which the output bus bar 18C overlaps with the end portion 182. Therefore, the output bus bar 18C can be manufactured by pressing the sheet metal, and the manufacturability is improved.
Further, according to the third modification, the second end portion 183C is located between the second end portion 183C and the external bus bar 80 because the portion 1832 extending in the Y direction on the Z1 side in the Z direction is exposed from the resin mold portion 19C. It becomes easy to secure a relatively large joint range. Thereby, the joint area (conduction area) between the output bus bar 18C and the external bus bar 80 can be effectively expanded. Further, for the same reason, the range of the welded portion 84 can be expanded. Thereby, the reliability of the welded portion 84 can be improved.
Further, according to the third modification, in the second end portion 183C, the portion 1831 extending for a predetermined length in the Y direction on the Z direction Z2 side is exposed from the resin mold portion 19C, so that the flow path forming portion 38 is used. The cooling performance of the output bus bar 18D and the cooling performance of the inverter module 10 can be effectively improved accordingly.

FIG. 14 is a cross-sectional view schematically showing the inverter module 10D according to the fourth modification. FIG. 14 is a cross-sectional view along a cut surface corresponding to the cross-sectional view shown in FIG. 7. Note that FIG. 14 also shows the external bus bar 80 and the welded portion 84.

The inverter module 10D according to the fourth modification differs from the above-mentioned inverter module 10 in that the output bus bar 18 is replaced by the output bus bar 18D, and the resin mold portion 19 is replaced by the resin mold portion 19D accordingly. The point is different.

The output bus bar 18D is mainly different from the output bus bar 18 according to the above-described embodiment in that the first end portion 182 and the second end portion 183 are replaced by the first end portion 182D and the second end portion 183D, respectively. .. Specifically, the output bus bar 18D includes a main body portion 181, a first end portion 182D, and a second end portion 183D.

The second end portion 183D is formed on the Y1 side of the first end portion 182D in the Y direction. That is, the second end portion 183D extends between the main body portion 181 and the first end portion 182D in the Y direction. In this case, the second end portion 183D is a portion having an L-shaped cross section extending on the Y2 side of the main body portion 181 in the Y direction, and the portion extending a predetermined length in the Y direction on the Z1 side in the Z direction is Z. The surface on the direction Z1 side is exposed from the resin mold portion 19D. The surface of the second end portion 183D on the Z direction Z1 side exposed from the resin mold portion 19D may be flush with the surface of the resin mold portion 19D on the Z direction Z1 side.
The first end portion 182D extends from the end portion of the second end portion 183D on the Y2 side in the Y direction, extends in the Z direction toward the Z2 side in the Z direction, and the end surface on the Z2 side in the Z direction extends from the resin mold portion 19D. Be exposed. The end surface of the first end portion 182D on the Z direction Z2 side may be flush with the surface of the resin mold portion 19D on the Z direction Z2 side.

In the fourth modification, as shown in FIG. 13, the surface of the second end portion 183D is joined to the external bus bar 80 at a portion extending a predetermined length in the Y direction on the Z1 side in the Z direction. NS. FIG. 13 schematically shows a welded portion 84 between the second end portion 183D and the external bus bar 80.

The resin mold portion 19D only has a change (change regarding the dimensions in the Y direction, etc.) from the output bus bar 18 to the output bus bar 18D with respect to the resin mold portion 19 of the inverter module 10 described above. Is the same.

Even with such a fourth modification, the same effect as that of the above-described embodiment can be obtained. In particular, according to the fourth modification, since the second end portion 183D is provided on the Y1 side in the Y direction with respect to the first end portion 182D, the above-described embodiment (the second end portion 183 is the first when viewed in the Z direction). The output bus bar 18D can be formed to have a constant plate thickness, unlike the configuration in which the output bus bar 18D overlaps with the end portion 182. Therefore, the output bus bar 18D can be manufactured by pressing the sheet metal, and the manufacturability is improved.
Further, according to the fourth modification, the portion of the second end portion 183D extending for a predetermined length in the Y direction on the Z1 side in the Z direction is exposed from the resin mold portion 19D, so that the portion between the second end portion 183D and the external bus bar 80 is exposed. It becomes easy to secure a relatively large joining range. Thereby, the joint area (conduction area) between the output bus bar 18D and the external bus bar 80 can be effectively expanded. Further, for the same reason, the range of the welded portion 84 can be expanded. Thereby, the reliability of the welded portion 84 can be improved.

FIG. 15 is a cross-sectional view schematically showing the inverter module 10E according to the fifth modification. FIG. 15 is a cross-sectional view along a cut surface corresponding to the cross-sectional view shown in FIG. 7. Note that FIG. 15 also shows the external bus bar 80 and the welded portion 84.

The inverter module 10E according to the fifth modification is different from the above-mentioned inverter module 10 in that the resin mold portion 19 is replaced with the resin mold portion 19E and the insulating coating layer 70 is added.

The resin mold portion 19E is different from the resin mold portion 19 according to the above-described embodiment in that the surface layer on the Z direction Z1 side of the resin mold portion 19 and the thickness d0 is removed. The insulating coating layer 70 (an example of a part of the insulating portion) is provided instead of the surface layer having a thickness d0 of the resin mold portion 19, and functions in the same manner as the surface layer. Specifically, when the surface layer of the resin mold portion 19 on the Z direction Z1 side and the thickness d0 is removed, the surface of the main body portion 151 of the negative electrode bus bar 15 on the Z direction Z1 side and the output bus bar 16, The surfaces of the main bodies 161, 171 and 181 of 17 and 18 on the Z1 side in the Z direction are exposed. The insulating coating layer 70 electrically insulates between the main bodies 151, 161, 171 and 181 by covering the surfaces of the main bodies 151, 161 and 171 and 181 on the Z1 side in the Z direction.

Even with such a fifth modification, the same effect as that of the above-described embodiment can be obtained. The fifth modification may be realized in combination with the above-mentioned first modification to the fourth modification. That is, in any of the first to fourth modifications described above, the surface layer having a thickness d0 is removed from the resin mold portions 19A to 19D, and instead, an insulating coating layer corresponding to the insulating coating layer 70 is provided. It may be granted.

Although each embodiment has been described in detail above, the present invention is not limited to a specific embodiment, and various modifications and changes can be made within the scope of the claims. It is also possible to combine all or a plurality of the components of the above-described embodiment.

For example, in the above-described embodiment, with respect to the bus bar, the main body portions 141, 151, 161, 171, 181 have the same plate thickness, but one or more of the main body portions 141, 151, 161, 171 and 181 , It may have a plate thickness different from the others. In this case, a slight step corresponding to the difference in plate thickness may be formed on the surface of the resin mold portion 19 on the Z direction Z1 side.

Further, in the above-described embodiment, as shown in FIG. 7, when the surface layer on the Z-direction Z1 side of the resin mold portion 19 and having a thickness d0 is removed, the Z of the main body portion 151 of the negative electrode bus bar 15 is removed. The surface on the Z1 side of the direction Z1 and the surface on the Z1 side of the main bodies 161, 171, 181 of the output bus bars 16, 17, and 18 are exposed, but the present invention is not limited to this. For example, when the surface layer of the resin mold portion 19 on the Z direction Z1 side and the thickness d0 is removed, the surface of the main body portion 151 of the negative electrode bus bar 15 on the Z direction Z1 side and the output bus bars 16 and 17, Only any one of the surfaces of the main body portions 161, 171 and 181 on the Z1 side in the Z direction may be exposed. For example, when the surface layer of the resin mold portion 19 on the Z direction Z1 side and the thickness d0 is removed, the main body portion of the surfaces of the main body portions 151, 161, 171 and 181 on the Z direction Z1 side. Only the surface on the Z1 side in the Z direction of 151 may be exposed.

<Additional notes>
Regarding the above examples, the following will be further disclosed. Of the effects described below, the effect related to each additional form with respect to one form is an additional effect resulting from each of the additional forms.

(1) One form is a power converter (10, 10A, 10B, 10C, 10D, 10E) electrically connected between the vehicle-mounted power supply (2) and the rotary electric machine (5).
With multiple busbars (14-18),
A semiconductor chip (11) electrically connected to the plurality of bus bars,
An insulating portion provided so as to cover a part of the plurality of bus bars and the semiconductor chip, and is a flat first surface perpendicular to the first direction (Z1) on the first side (Z1) of the first direction (Z). Includes insulating portions (19, 19A, 19B, 19C, 19D, 19E, 70) having a surface region (191).
The plurality of bus bars are defined in advance to be larger than 0 on the first side of the insulating portion in the insulating portion in the first direction and in a region overlapping the first surface region when viewed in the first direction. A power converter comprising a first bus bar (16, 17, 18, 18A, 18B, 18C, 18D) and a second bus bar (15) that are close to each other up to a distance (Δ1).

According to this embodiment, in the region overlapping the first surface region of the insulating portion when viewed in the first direction, the first bus bar and the second bus bar can be electrically insulated by the insulating portion. Using the surface area, it becomes easy to secure the required creepage distance between a plurality of bus bars. Further, in the region overlapping the first surface region of the insulating portion when viewed in the first direction, the first bus bar and the second bus bar are electrically insulated by the insulating portion, so that the first bus bar and the second bus bar are second. Busbars can be brought closer to the first distance. By bringing the first bus bar and the second bus bar close to each other up to the first distance, it is possible to reduce the size of the power converter. In this way, according to this embodiment, it is possible to reduce the size of the power converter while ensuring the required creepage distance between the plurality of bus bars.

(2) Further, in the present embodiment, preferably, the first bus bar and the second bus bar have a creepage distance along the surface of the insulating portion and a creepage distance larger than the first distance, and each other. On the other hand, it is electrically insulated.

In this case, a creepage distance larger than the first distance can be secured between the first bus bar and the second bus bar. In other words, by making the first distance smaller than the creepage distance secured between the first bus bar and the second bus bar, it is possible to reduce the size of the power converter.

(3) Further, in the present embodiment, preferably, the insulating portion is placed on the second side (Z2) of the first direction opposite to the first side, and the first side as viewed in the first direction. It has a planar second surface area (192) that overlaps the surface area.
The second surface region forms a boundary surface (190, 38A) when the power converter is thermally connected to the cooling device (38).

In this case, the heat generated by the power converter can be transferred to the cooling device through the planar second surface region. Further, since the first surface region and the second surface region overlap each other when viewed in the first direction, the power converter and the power converter can be used, for example, by using a jig or the like that makes surface contact with the first surface region at the time of assembly. Thermal resistance through the second surface region between the cooling devices can be reduced.

(4) Further, in the present embodiment, preferably, the first bus bar and the second bus bar have their respective surfaces on the first side in the first direction at positions close to the first distance. It is offset to the second side by the same distance (d0) with respect to the surface of the first side of the insulating portion.

In this case, the insulating portion can keep the thickness (d1) of the region portion overlapping the first bus bar and the second bus bar when viewed in the first direction in the first surface region. Further, when another bus bar having the same plate thickness as the second bus bar is arranged on the second side in the first direction with respect to the first bus bar, the other bus bar and the first bus bar are in the same plane. It becomes easy to arrange the other bus bar and the first bus bar so as to have a surface on the second side in the first direction.

(5) Further, in the present embodiment, preferably, the first bus bar extends in the second direction (Y) orthogonal to the first direction.
The second bus bar extends in a third direction (X) orthogonal to both the first direction and the second direction.
The first bus bar and the second bus bar intersect with each other when viewed in the first direction, and sandwich one of the semiconductor chips in the first direction between them.

In this case, the semiconductor chip can be arranged between the first bus bar and the second bus bar that intersect in the first direction. Further, by bringing the first bus bar and the second bus bar close to each other up to the first distance in the second direction, the dimensions of the power converter in the second direction can be effectively reduced.

(6) Further, in the present embodiment, preferably, the first bus bar is exposed from the insulating portion on one side of the second direction and on the first side of the first direction, and is exposed in the second direction. On the other side of the above and on the second side in the first direction, it is exposed from the insulating portion.
The second bus bar is exposed from the insulating portion on both sides or either side of the third direction and on the first side or the second side of the first direction.

In this case, the first bus bar can be exposed from the insulating portion on the first side in the first direction and joined to the external bus bar. Further, it becomes easy to secure a necessary creepage distance between the portion of the first bus bar exposed from the insulating portion and the portion of the second bus bar exposed from the insulating portion.

(7) Further, in the present embodiment, preferably, the first bus bar is further exposed from the insulating portion on the one side of the second direction and the second side of the first direction.

In this case, since heat can be efficiently transferred from the first bus bar to the cooling device on both sides of the second direction and on the second side of the first direction, the first bus bar can be efficiently cooled.

(8) Further, in the present embodiment, preferably, the first bus bar is provided in association with each phase of the rotary electric machine.
The second bus bar is provided in association with the negative electrode side of the vehicle-mounted power supply.
Further including a third bus bar (14) provided in association with the positive electrode side of the vehicle-mounted power supply.
The third bus bar extends in the third direction alongside the second bus bar in the second direction, and in a region that overlaps with the first surface region when viewed in the first direction, the first direction. Exposed from the insulating portion on the second side of the
The first bus bar and the third bus bar intersect with each other when viewed in the first direction, and sandwich the other semiconductor chip between them in the first direction.

In this case, by sandwiching the semiconductor chip between the first bus bar, the second bus bar, and the third bus bar while crossing the first bus bar, the second bus bar, and the third bus bar, the first bus bar, the second bus bar, and the third bus bar are inserted. Since the third bus bar can be efficiently arranged together with the semiconductor chip, the power converter can be miniaturized. Further, in such an efficient arrangement, by bringing the first bus bar and the second bus bar close to each other up to the first distance as described above, the dimension of the power converter in the second direction can be effectively reduced.

(9) Further, in the present embodiment, preferably, the first bus bar and the third bus bar are defined in advance to be larger than 0 on the second side of the insulating portion in the first direction with respect to the center. While being close to each other up to 2 distances (Δ2), they are exposed from the insulating portion.
The second distance is larger than the first distance.

In this case, heat can be efficiently transferred from the first bus bar and the third bus bar to the cooling device while separating the first bus bar and the third bus bar by a second distance on the second side in the first direction.

(10) Further, in the present embodiment, preferably, the first distance is a creepage distance along the surface of the insulating portion, and the creepage to be secured between the first bus bar and the second bus bar. It is smaller than the lower limit for distance.

In this case, the power converter can be miniaturized by making the first distance smaller than the lower limit value related to the creepage distance.

1 Motor drive system for electric vehicles 2 High-pressure battery 3 Smoothing capacitor 4 Inverter 5 Traveling motor 6 Inverter control device 10, 10A, 10B, 10C, 10D, 10E Inverter module 11 Chip 13 Control wiring 14 Positive bus bar 141 Main body 142 End 15 Negative bus bar 151 Main body 152 End 16 Output bus bar 161 Main body 162 1st end 163 2nd end 17 Output bus bar 171 Main body 172 1st end 173 2nd end 18, 18A, 18B, 18C, 18D Output Busbars 181 and 181A Main body 182, 182D First end 183, 183A, 183B, 183C, 183D Second end 19, 19A, 19B, 19C, 19D, 19E Resin mold 191 Surface area 192 Surface area 20 Capacitor module 30 Capacitor case 38 Flow path forming part 40 Control board 42 Connector 50 Shield plate 70 Insulation coating layer 80 External bus bar 84 Welding part 90 Joint layer 91, 92 Flexible printed board

Claims (10)

A power converter that is electrically connected between an in-vehicle power supply and a rotary electric machine.
With multiple busbars
A semiconductor chip electrically connected to the plurality of bus bars and
An insulating portion provided so as to cover a part of the plurality of bus bars and the semiconductor chip, and having a planar first surface region perpendicular to the first direction on the first side in the first direction. Including and
The plurality of bus bars are defined in advance to be larger than 0 on the first side of the insulating portion in the first direction with respect to the center of the insulating portion in the region overlapping the first surface region when viewed in the first direction. A power converter that includes a first busbar and a second busbar that are close to each other up to a distance. The first bus bar and the second bus bar are electrically insulated from each other at a creepage distance along the surface of the insulating portion and larger than the first distance, according to claim 1. The power converter described. The insulating portion has a planar second surface region that overlaps the first surface region when viewed in the first direction on the second side of the first direction opposite to the first side.
The power converter according to claim 1, wherein the second surface region forms a boundary surface when the power converter is thermally connected to the cooling device. At a position close to the first distance, the first bus bar and the second bus bar have their respective surfaces on the first side in the first direction with respect to the surface on the first side in the insulating portion. The power converter according to claim 3, wherein the power converter is offset to the second side by the same distance. The first bus bar extends in a second direction orthogonal to the first direction.
The second bus bar extends in a third direction orthogonal to both the first direction and the second direction.
The power converter according to claim 4, wherein the first bus bar and the second bus bar intersect with each other when viewed in the first direction, and sandwich one semiconductor chip in the first direction between them. The first bus bar is exposed from the insulating portion on one side of the second direction and on the first side of the first direction, and is on the other side of the second direction and on the second side of the first direction. Exposed from the insulating part with
The power converter according to claim 5, wherein the second bus bar is exposed from the insulating portion on both sides or either side of the third direction and on the first side or the second side of the first direction. The power converter according to claim 6, wherein the first bus bar is further exposed from the insulating portion on one side of the second direction and on the second side of the first direction. The first bus bar is provided in association with each phase of the rotary electric machine.
The second bus bar is provided in association with the negative electrode side of the vehicle-mounted power supply.
Further including a third bus bar provided in association with the positive electrode side of the vehicle-mounted power supply.
The third bus bar extends in the third direction alongside the second bus bar in the second direction, and in a region that overlaps with the first surface region when viewed in the first direction, the first direction. Exposed from the insulating portion on the second side of the
The electric power according to claim 6 or 7, wherein the first bus bar and the third bus bar intersect each other in the first direction while sandwiching another semiconductor chip between them in the first direction. converter. The first bus bar and the third bus bar are exposed from the insulating portion on the second side of the insulating portion in the first direction while being close to each other up to a predetermined second distance greater than 0. death,
The power converter according to claim 8, wherein the second distance is larger than the first distance. Claims 1 to 1, wherein the first distance is a creepage distance along the surface of the insulating portion and is smaller than a lower limit value regarding a creepage distance to be secured between the first bus bar and the second bus bar. The power converter according to any one of 9.

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