Power conversion device

Abstract

To provide a power conversion device in which a heating value of a bus bar is reduced.SOLUTION: A power conversion device 6 includes a power card 24, a cooler 21, input terminals 60P, 60N, a capacitor 30, input bus bars 61P, 61N, a current detection unit 40, output terminals 70U, 70V, 70W, and output bus bars 71U, 71V, 71W. A virtual surface VS that is orthogonal to the arrangement direction of a P terminal 24P, an N terminal 24N, and an O terminal 24O of the power card 24, defines an input-side region Ain and an output-side region Aout. The input-side region Ain is a region including the P terminal 24P and the N terminal 24N. The output-side region Aout is a region including the O terminal 24O. A plurality of the input terminals 60P, 60N and the capacitor 30 are disposed in the input-side region Ain. A plurality of the output terminals 70U, 70V, 70W, and the current detection unit 40 are disposed in the output-side region Aout.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The disclosure in this specification relates to a power conversion device.

Background Art

[0002] Patent Document 1 describes a power conversion device including a semiconductor module, a capacitor, a current detection unit, etc. A plurality of semiconductor modules form upper and lower arm circuits, convert DC power supplied from an external battery into AC, and output it to an external motor. The capacitor is connected in parallel with the semiconductor module to smooth voltage pulsations. The current detection unit detects the magnitude of the current output to the motor.

[0003] Furthermore, the power conversion device includes an input terminal electrically connected to the external battery and an input bus bar electrically connecting the capacitor to the input terminal. Furthermore, the power conversion device includes an output terminal electrically connected to the external motor and an output bus bar electrically connecting the current detection unit to the output terminal.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Now, among the components of the power conversion device, the semiconductor module forming the upper and lower arm circuits generates the most heat, and this type of semiconductor module is generally thermally managed with a cooler. Then, when the above-mentioned input bus bar and output bus bar are long, the heat generation amount in those bus bars becomes non-negligible. For example, the temperature of the capacitor rises due to radiant heat from the bus bar, and the performance degradation of the capacitor becomes significant.

[0006] One of the disclosed objects is to provide a power conversion device that reduces the heat generation amount of a bus bar.

Means for Solving the Problem

[0007] To achieve the above object, one of the disclosed means is a plurality of semiconductor modules (24) each incorporating a semiconductor element and arranged in a predetermined stacking direction, a metal cooler (21) for cooling the plurality of semiconductor modules, an inflow pipe (22) for allowing a refrigerant to flow into the cooler, and a cooling unit (20) having an outflow pipe (23) for allowing the refrigerant to flow out from the cooler, input terminals (60P, 60N) electrically connected to an external battery (2) and supplied with power from the battery, a capacitor (30) electrically connected in parallel to the plurality of semiconductor modules and the battery to smooth the voltage pulsation of the power supplied from the input terminals, input bus bars (61P, 61N) electrically connecting the capacitor and the input terminals, a current detection unit (40) for detecting the magnitude of the alternating current output from the semiconductor module, output terminals (70U, 70V, 70W) electrically connected to an external motor (3) and outputting the alternating current to the motor, output bus bars (71U, 71V, 71W) electrically connecting the current detection unit and the output terminals, and the semiconductor modules are terminals arranged side by side in a direction perpendicular to the stacking direction, and have a P terminal (24P) electrically connected to the high potential side of the capacitor, an N terminal (24N) electrically connected to the low potential side of the capacitor, and an O terminal (24O) electrically connected to the current detection unit, Of the regions partitioned into two by a virtual plane (VS) perpendicular to the direction in which the P terminal, N terminal, and O terminal are arranged, the region including the P terminals and N terminals of the plurality of semiconductor modules is defined as an input side region (Ain), and the region including the O terminals of the plurality of semiconductor modules is defined as an output side region (Aout), the plurality of input terminals are arranged in the input side region together with the capacitor, The plurality of output terminals are arranged in the output side region together with the current detection unit, at least a part of the cooling unit is provided between the input bus bar and the output bus bar, and The P terminal, N terminal, and O terminal extend in an extending direction perpendicular to both the stacking direction and the arranging direction in the semiconductor module, The capacitor and the current detection unit are arranged in the semiconductor module in a direction orthogonal to the extending direction and it is a power conversion device.

[0008] According to the power conversion device disclosed herein, the plurality of input terminals are arranged in the input side region together with the capacitor. Therefore, the length of the input bus bar connecting the capacitor and the input terminals can be shortened as compared with the case where the input terminals are arranged in the output side region. Also, the plurality of output terminals are arranged in the output side region together with the current detection unit. Therefore, the length of the output bus bar connecting the current detection unit and the output terminals can be shortened as compared with the case where the output terminals are arranged in the input side region.

[0009] As described above, the input bus bar and the output bus bar can be shortened, so that the amount of heat generated by these bus bars can be reduced. Thus, it is possible to prevent another electrical component separate from the semiconductor module from degrading in performance due to radiant heat from the bus bar. Specific examples of the above electrical components include capacitors and current detection units.

[0010] Note that the reference numerals in the parentheses above merely show an example of the correspondence with the specific configuration in the embodiments described later, and do not limit the technical scope in any way.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0012] Hereinafter, a plurality of embodiments of the present disclosure will be described with reference to the drawings. In each embodiment, the same reference numerals may be given to corresponding components, and redundant descriptions may be omitted. When only a part of the configuration is described in each embodiment, the configuration of the other embodiments described previously can be applied to the other parts of the configuration.

[0013] (First Embodiment) The vehicle V shown in FIG. 1 includes a battery 2, a motor 3, an electronic control unit (ECU 4), a radiator 5, and a power conversion device 6. The arrows indicated by the reference numerals FD, BD, LD, and RD in the figure indicate the front-rear direction and the left-right direction of the vehicle V. The reference numerals FD and BD indicate the front and the rear, and the reference numerals LD and RD indicate the left and the right.

[0014] The power conversion device 6 converts the DC power supplied from the battery 2 into AC power and outputs it to the motor 3. The battery 2 and the power conversion device 6 are electrically connected by an input cable 2a, and DC power is supplied from the battery 2 to the power conversion device 6 through the input cable 2a. The power conversion device 6 and the motor 3 are electrically connected by an output cable 3a, and three-phase AC power is output from the power conversion device 6 to the motor 3 through the output cable 3a.

[0015] The rotational output of the motor 3 is transmitted to the drive wheels 7 of the vehicle V via a speed reducer (not shown) and is exerted as the running torque of the vehicle V. Note that there is one running motor 3 mounted on the vehicle V, and there is one motor 3 to which the power conversion device 6 outputs power.

[0016] The power conversion device 6 is integrally configured with the motor 3. Specifically, the case 10 (see FIG. 2) of the power conversion device 6 is bolted to the housing 3b of the motor 3 and integrated. Alternatively, the case 10 and the housing 3b are integrally metal - processed by die - casting or the like. The motor 3 is mounted in a direction such that the axial center direction of the motor rotation shaft coincides with the left - right direction of the vehicle V. The power conversion device 6 is disposed above the motor 3. The power conversion device 6 and the motor 3 are electrically connected by an output cable 3a.

[0017] The ECU 4 and the power conversion device 6 are electrically connected by a communication cable 4a, and signals are transmitted and received bidirectionally through the communication cable 4a. For example, a signal representing the required value of the motor 3 output is transmitted from the ECU 4 to the power conversion device 6. A detection signal representing the magnitude of the output alternating current is transmitted from the power conversion device 6 to the ECU 4.

[0018] The radiator 5 is a device that cools the refrigerant by traveling wind and is connected to the power conversion device 6 by a refrigerant hose 5a. The refrigerant circulates between the radiator 5 and the power conversion device 6 via the refrigerant hose 5a. Thereby, the power conversion device 6 is cooled by the refrigerant.

[0019] As shown in FIGS. 2 and 3, the power conversion device 6 includes a case 10, a semiconductor unit 20, a capacitor 30, a current detection unit 40, and a control board 50. Further, the power conversion device 6 includes an input terminal block 60, an output terminal block 70, and a signal connector 80 disposed and attached to the opening of the case 10. Further, the power conversion device 6 includes an upper - arm busbar 25P, a lower - arm busbar 25N, a mid - point busbar 25O, input busbars 61P, 61N, and output busbars 71U, 71V, 71W, which are plate - shaped conductive members.

[0020] The case 10 is made of metal and has a main body portion 11 and a lid portion 12. Note that the illustration of the lid portion 12 is omitted in FIG. 2. The main body portion 11 has a shape with an opening 6a that opens to the front side (upper side) in the direction perpendicular to the paper surface of FIG. 2. The lid portion 12 is bolted to the main body portion 11 to close the opening 6a. The semiconductor unit 20, the capacitor 30, the current detection unit 40, and the control board 50 are inserted through the opening 6a and housed inside the case 10.

[0021] The semiconductor unit 20 includes a plurality of power cards 24 (semiconductor modules), a cooler 21, an inflow pipe 22, and an outflow pipe 23.

[0022] The power card 24 is in a card shape resin-molded to house semiconductor elements. The semiconductor elements are switching elements that function as an inverter circuit to convert the input DC power into three-phase AC of a predetermined frequency and output it to the motor 3. This inverter circuit also has a function of converting the AC power generated by the motor 3 into DC power. The power cards 24 are provided for each of the three phases of the motor 3. The power cards 24 have an upper arm and a lower arm that are connected in series with each other. The upper arm and the lower arm together are called the upper and lower arm circuit.

[0023] In this embodiment, an insulated gate bipolar transistor (IGBT) is adopted as the switching element constituting each arm. One power card 24 houses two IGBTs. The two IGBTs form the upper arm and the lower arm respectively. The upper and lower arm circuits output to each phase of the motor 3 are provided by two power cards 24 connected in parallel. Thereby, even when one power card 24 fails, the motor 3 can be driven by the other power card 24, achieving functional redundancy.

[0024] The power card 24 has a P terminal 24P, an N terminal 24N, and an O terminal 24O. The collector electrode of the IGBT in the upper arm is connected to the P terminal 24P. The emitter electrode of the IGBT in the lower arm is connected to the N terminal 24N. The emitter electrode of the IGBT in the upper arm and the collector electrode of the IGBT in the lower arm are connected to the O terminal 24O.

[0025] A plurality of power cards 24 are arranged side by side in a predetermined stacking direction. The power conversion device 6 is mounted on the vehicle V such that the stacking direction coincides with the vehicle front-rear direction. The P terminal 24P, the N terminal 24N, and the O terminal 24O extend upward from the molded resin of the power card 24 and are arranged side by side linearly. The direction in which these terminals are arranged is a direction perpendicular to the stacking direction and coincides with the axial center direction of the motor rotation axis, that is, the left-right direction of the vehicle V.

[0026] The cooler 21 is made of metal and forms a refrigerant passage inside for circulating the refrigerant cooled by the radiator 5. The refrigerant passage includes an inter-layer passage described below. The inter-layer passage is a passage that flows between a plurality of power cards 24 in a direction perpendicular to the stacking direction (for example, the left-right direction of the vehicle).

[0027] One ends of the inflow pipe 22 and the outflow pipe 23 are connected to the cooler 21, and the other ends are connected to the refrigerant hose 5a. The inflow pipe 22 and the outflow pipe 23 are connected to the front side portion of the cooler 21 in the vehicle and extend in the stacking direction, that is, the vehicle front-rear direction. In other words, the inflow pipe 22 and the outflow pipe 23 extend from the portion of the power conversion device 6 facing the radiator 5 toward the radiator 5.

[0028] The refrigerant cooled by the radiator 5 flows into the refrigerant passage from the inflow pipe 22, flows through the inter-layer passage, and then flows out from the outflow pipe 23. The portion of the cooler 21 that forms the inter-layer passage is in contact with both sides of the power card 24. Therefore, the heat generated in the semiconductor element incorporated in the power card 24 is radiated from both sides of the power card 24 to the cooler 21.

[0029] The P terminal 24P is connected to the upper arm bus bar 25P, the N terminal 24N is connected to the lower arm bus bar 25N, and the O terminal 24O is connected to the neutral point bus bar 25O. These connections may be made by bolt fastening or welding.

[0030] The capacitor 30 is electrically connected in parallel to the power card 24 and the battery 2, and smoothes the voltage pulsation of the power supplied from the battery 2. The electrode on the high potential side of the capacitor 30 is electrically connected to the upper arm bus bar 25P, and thus is electrically connected to the P terminal 24P. The electrode on the low potential side of the capacitor 30 is electrically connected to the lower arm bus bar 25N, and thus is electrically connected to the N terminal 24N.

[0031] The capacitor 30 has an electrode in the shape of a wound film, a case for accommodating a plurality of electrodes, and a resin material filled in the case for electrically insulating and holding the film. Among the plurality of electrodes, a pair of opposing electrodes form one capacitance portion, and the plurality of capacitance portions are connected in parallel.

[0032] One end of the input bus bar 61P is connected to the connection portion 25Pa of the upper arm bus bar 25P, and the input terminal 60P is connected to the other end of the input bus bar 61P. One end of the input bus bar 61N is connected to the connection portion 25Na of the lower arm bus bar 25N, and the input terminal 60N is connected to the other end of the input bus bar 61N. Each of these connections may be made by bolt fastening or welding.

[0033] The input terminal block 60 is made of resin having electrical insulation properties and holds a plurality of input terminals 60P, 60N. The input terminals 60P, 60N are held in a state of being exposed from the opening 60a of the input terminal block 60. The input terminals 60P, 60N are arranged side by side in the vehicle left - right direction. The input terminal block 60 is connector - connected to a connector portion (not shown) provided at one end of the input cable 2a. Thereby, the plurality of input terminals 60P, 60N are electrically connected to the battery 2 outside the power conversion device 6 via the input cable 2a.

[0034] The current detection unit 40 includes a current sensor 41 and a holding member 43. The holding member 43 is made of resin having electrical insulation properties and holds the connection portion 25Oa of the neutral point bus bar 25O and the current sensor 41. The neutral point bus bar 25O and the current sensor 41 are provided for each of the U-phase, V-phase, and W-phase of the three-phase alternating current. The current sensor 41 detects the magnitude of the alternating current of each phase output from the semiconductor unit 20 without contact with the neutral point bus bar 25O.

[0035] One end of output bus bars 71U, 71V, and 71W is connected to the connection portion 25Oa of the neutral point bus bar 25O. Output terminals 70U, 70V, and 70W are connected to the other ends of the output bus bars 71U, 71V, and 71W. The connection between these output bus bars 71U, 71V, and 71W and the output terminals 70U, 70V, and 70W may be by bolt fastening or welding.

[0036] The output terminal block 70 is made of resin having electrical insulation properties and holds a plurality of output terminals 70U, 70V, and 70W. The output terminals 70U, 70V, and 70W are held in a state of being exposed from the opening 70a of the output terminal block 70. The output terminals 70U, 70V, and 70W are arranged side by side in the vehicle longitudinal direction. The output terminal block 70 is connected to one end of the output cable 3a. The connection between these output terminals 70U, 70V, and 70W and the output cable 3a may be by bolt fastening or welding. Thereby, the plurality of output terminals 70U, 70V, and 70W are electrically connected to each of the U-phase winding, V-phase winding, and W-phase winding of the motor 3 via the output cable 3a.

[0037] The signal connector 80 is connector-connected to a connector portion (not shown) provided at one end of the communication cable 4a. The signal connector 80 is connected to the control board 50 by a signal line (not shown). Thereby, the control board 50 is electrically connected to the ECU 4 outside the power conversion device 6 via the communication cable 4a. Electronic components 51 such as a microcomputer (microcontroller) and switching elements are mounted on the control board 50. The microcontroller has a processor and a memory that execute various arithmetic processes.

[0038] Based on the torque request input from the ECU 4 and the signals detected by various sensors, the control board 50 outputs a gate signal to the IGBT built into the power card 24. Specific examples of various sensors include a current sensor 41, a voltage sensor, a rotation angle sensor, and the like. As described above, the current sensor 41 detects the magnitude of the alternating current in each phase. One of the voltage sensors detects the voltage at the high-potential side terminal of the capacitor 30, that is, the voltage of the P terminal 24P. The rotation angle sensor detects the rotation angle of the rotor of the motor 3.

[0039] Next, based on FIGS. 2 and 3, the arrangement of the components of the power conversion device 6 will be described. In the following description, the plane perpendicular to the direction in which the P terminal 24P, the N terminal 24N, and the O terminal 24O are arranged, that is, the vehicle left-right direction, is called a virtual plane VS. Of the regions within the case 10 partitioned into two by the virtual plane VS, one is called an input-side region Ain and the other is called an output-side region Aout. The input-side region Ain is the region including the P terminals 24P and N terminals 24N of the plurality of power cards 24. The output-side region Aout is the region including the O terminals 24O of the plurality of power cards 24.

[0040] The plurality of input terminals 60P, 60N are arranged in the input-side region Ain together with the capacitor 30. More specifically, the input terminal block 60, the capacitor 30, the upper arm bus bar 25P, the lower arm bus bar 25N, and the input bus bars 61P, 61N are arranged in the input-side region Ain.

[0041] The plurality of output terminals 70U, 70V, 70W are arranged in the output-side region Aout together with the current detection unit 40. More specifically, the output terminal block 70, the signal connector 80, the current detection unit 40, the midpoint bus bar 25O, and the output bus bars 71U, 71V, 71W are arranged in the output-side region Aout.

[0042] As shown in FIG. 2, the input terminal block 60 is arranged on the vehicle rear side of the semiconductor unit 20, and the opening 60a is arranged in a direction facing the vehicle rear. The output terminal block 70 is arranged on the vehicle right side of the semiconductor unit 20, and the opening 70a is arranged in a direction facing the vehicle right. As shown in FIG. 3, the entire upper arm bus bar 25P, lower arm bus bar 25N, and midpoint bus bar 25O are located above the cooler 21.

[0043] The control board 50 is arranged below the semiconductor unit 20, the capacitor 30, and the current detection unit 40. The semiconductor unit 20, the capacitor 30, and the current detection unit 40 are arranged side by side in the vehicle left - right direction. The capacitor 30 and the current detection unit 40 are respectively arranged on both sides of the semiconductor unit 20.

[0044] The control board 50 has a rectangular shape that extends perpendicular to the vertical direction. When viewed from above or below, the entire semiconductor unit 20 is located inside the control board 50. In other words, the entire semiconductor unit 20 is located within the vertical projection range of the control board 50. Similarly, the entire capacitor 30 and the current detection unit 40 are located within the vertical projection range of the control board 50.

[0045] Hereinafter, the effects of the power conversion device having the above - described configuration will be described.

[0046] Now, the power conversion device 6 according to the present embodiment is an inverter for one motor having one motor 3 as a power output target. In this type of inverter, it may be desirable to separately arrange the capacitor 30 and the current detection unit 40 on both sides (both sides in the stacking orthogonal direction) of the semiconductor unit 20. The external connection terminals of this type of inverter include input terminals 60P, 60N connected to an external battery 2, and output terminals 70U, 70V, 70W connected to an external motor 3.

[0047] Among the input-side region Ain and the output-side region Aout partitioned by the virtual surface VS, if the input terminals 60P and 60N and the output terminals 70U, 70V, and 70W are arranged in the same region, the input bus bars 61P and 61N or the output bus bars 71U, 71V, and 71W will become long. For example, if both terminals are arranged in the output-side region Aout, the positions of the capacitor 30 and the input terminals 60P and 60N will be separated, so the input bus bars 61P and 61N will become long. Also, if both terminals are arranged in the input-side region Ain, the positions of the current detection unit 40 and the output terminals 70U, 70V, and 70W will be separated, so the output bus bars 71U, 71V, and 71W will become long.

[0048] In view of this point, in the present embodiment, since the plurality of input terminals 60P and 60N are arranged in the input-side region Ain together with the capacitor 30, the input bus bars 61P and 61N can be shortened. Also, since the plurality of output terminals 70U, 70V, and 70W are arranged in the output-side region Aout together with the current detection unit 40, the output bus bars 71U, 71V, and 71W can be shortened.

[0049] As described above, according to the present embodiment, since the input bus bars 61P and 61N and the output bus bars 71U, 71V, and 71W can be shortened, the amount of heat generated in these bus bars can be reduced. Therefore, it is possible to suppress the performance of electrical components such as the capacitor 30 and the current sensor 41 from deteriorating due to radiant heat from the bus bars.

[0050] (Second Embodiment) In the first embodiment described above, the input terminal block 60 is arranged on the vehicle rear side of the semiconductor unit 20. In contrast, in the present embodiment, the input terminal block 60 is arranged on the vehicle left side of the semiconductor unit 20 (see FIG. 4). The output terminal block 70 is arranged on the vehicle right side of the semiconductor unit 20 in the same manner as in the first embodiment. In other words, the input terminal block 60 and the output terminal block 70 are arranged on both sides of the semiconductor unit 20 when viewed from the vertical direction.

[0051] Further, the input terminal block 60 is arranged such that the opening 60a faces the left side of the vehicle. The output terminal block 70 is arranged such that the opening 70a faces the right side of the vehicle.

[0052] The range in which the cooler 21 is projected in the direction in which the P terminal 24P, N terminal 24N, and O terminal 24O are arranged (the left - right direction of the vehicle) is referred to as the projection range Ac. The plurality of output terminals 70U, 70V, 70W are arranged in the output - side region Aout and within the projection range Ac. Also, the plurality of input terminals 60P, 60N are arranged in the input - side region Ain and within the projection range Ac.

[0053] Thus, in this embodiment, the output terminals 70U, 70V, 70W are arranged within the projection range Ac of the cooler 21 in the output - side region Aout. Therefore, compared with the case where they are arranged outside the projection range Ac in the output - side region Aout, the positions of the current detection unit 40 and the output terminals 70U, 70V, 70W are closer. Thus, it is possible to promote shortening of the output busbars 71U, 71V, 71W and to promote reduction of the heat generation amount in the output busbars 71U, 71V, 71W. Note that the arrangement of the output terminals 70U, 70V, 70W described above is also adopted in the first embodiment, and the same effect is exhibited in the first embodiment.

[0054] Furthermore, in this embodiment, the input terminals 60P, 60N are arranged within the projection range Ac of the cooler 21 in the input - side region Ain. Therefore, compared with the case where they are arranged outside the projection range Ac in the input - side region Ain, the positions of the capacitor 30 and the input terminals 60P, 60N are closer. Thus, it is possible to promote shortening of the input busbars 61P, 61N and to promote reduction of the heat generation amount in the input busbars 61P, 61N.

[0055] Furthermore, in the present embodiment, the input terminal block 60 and the output terminal block 70 are arranged on both sides of the semiconductor unit 20 when viewed from the vertical direction. More specifically, when viewed from the vertical direction, the cooler 21 is located between the plurality of output terminals 70U, 70V, 70W and the plurality of input terminals 60P, 60N. Therefore, the metal cooler 21 effectively functions as an electromagnetic shielding member between the input terminals and the output terminals. Thus, it is possible to suppress the current from flowing less easily through the input terminals due to the influence of the electromagnetic field generated by the current flowing through the output terminals. Similarly, it is possible to suppress the current from flowing less easily through the output terminals due to the influence of the electromagnetic field generated by the current flowing through the input terminals.

[0056] Furthermore, in the present embodiment, the cooler 21 has a double-sided cooling structure that contacts and cools both sides of the power card 24. Therefore, compared with the case of a single-sided cooling structure, the number of interlayer passages included in the refrigerant passage increases. That is, the number of metal plates forming the interlayer passages arranged in the stacking direction increases. Thus, the above-described function of the cooler 21 as an electromagnetic shielding member can be further improved.

[0057] In the present embodiment as well, in the same manner as in the first embodiment, the input terminals 60P, 60N are arranged in the input-side region Ain together with the capacitor 30, and the output terminals 70U, 70V, 70W are arranged in the output-side region Aout together with the current detection unit 40. Therefore, in the same manner as in the first embodiment, the input busbars 61P, 61N and the output busbars 71U, 71V, 71W can be shortened, and the heat generation amount of the busbars can be reduced.

[0058] (Third Embodiment) In the present embodiment, the input terminal block 60 and the output terminal block 70 are arranged on the vehicle front side of the semiconductor unit 20 (see FIG. 5). Also, the input terminal block 60 and the output terminal block 70 are arranged such that the openings 60a, 70a face the vehicle front side.

[0059] Thus, in this embodiment, both the input terminal block 60 and the output terminal block 70 are arranged on the same side of the semiconductor unit 20 when viewed from the vertical direction. Therefore, the work of connecting the input cables 2a to the input terminals 60P and 60N and the work of connecting the output cables 3a to the output terminals 70U, 70V, and 70W can be performed from the same side. Accordingly, the workability of these connection operations can be improved.

[0060] Furthermore, in this embodiment, in addition to the input terminal block 60 and the output terminal block 70, the inflow pipe 22 and the outflow pipe 23 are also arranged on the same side. Therefore, the attachment work of attaching the refrigerant hose 5a to these pipes can also be performed from the same side as the above-described connection work. Accordingly, the workability of these operations can be improved when performing the connection work and the attachment work at the same time.

[0061] Note that also in this embodiment, in the same manner as in the second embodiment, the input terminals 60P and 60N are arranged in the input-side region Ain together with the capacitor 30, and the output terminals 70U, 70V, and 70W are arranged in the output-side region Aout together with the current detection unit 40. Therefore, the heat generation amount of the bus bar can be reduced in the same manner as in the second embodiment.

[0062] (Fourth Embodiment) In this embodiment, the input terminal block 60 is arranged on the vehicle front side of the semiconductor unit 20, and the output terminal block 70 is arranged on the vehicle right side of the semiconductor unit 20 (see FIG. 6). Further, the input terminal block 60 is arranged such that the opening 60a faces the vehicle front side, and the output terminal block 70 is arranged such that the opening 70a faces the vehicle right side.

[0063] And in this embodiment, when viewed from the vertical direction, the entire input terminals 60P and 60N are located within the projection range obtained by projecting the output terminals 70U, 70V, and 70W onto the cooler 21. The two virtual lines VL shown in FIG. 6 indicate the above projection range, and the range sandwiched by these virtual lines VL corresponds to the projection range.

[0064] In this embodiment as well, in the same manner as in the third embodiment, the input terminals 60P and 60N are arranged in the input-side region Ain together with the capacitor 30, and the output terminals 70U, 70V, and 70W are arranged in the output-side region Aout together with the current detection unit 40. Therefore, in the same manner as in the third embodiment, the heat generation amount of the bus bar can be reduced.

[0065] (Fifth Embodiment) In this embodiment, the input terminal block 60 and the output terminal block 70 are arranged on the rear side of the vehicle of the semiconductor unit 20 (see FIG. 7). Further, the input terminal block 60 and the output terminal block 70 are arranged such that the openings 60a and 70a face the rear side of the vehicle.

[0066] In short, in this embodiment, in the same manner as in the third embodiment shown in FIG. 5, both the input terminal block 60 and the output terminal block 70 are arranged on the same side with respect to the semiconductor unit 20 when viewed from the vertical direction. Therefore, in the same manner as in the third embodiment, the connection work of the input cable 2a and the connection work of the output cable 3a can be performed from the same side, and the workability of the connection work can be improved.

[0067] In this embodiment as well, in the same manner as in the fourth embodiment, the input terminals 60P and 60N are arranged in the input-side region Ain together with the capacitor 30, and the output terminals 70U, 70V, and 70W are arranged in the output-side region Aout together with the current detection unit 40. Therefore, in the same manner as in the fourth embodiment, the heat generation amount of the bus bar can be reduced.

[0068] (Other Embodiments) As described above, a plurality of embodiments of the present disclosure have been described. However, not only the combinations of the configurations explicitly shown in the description of each embodiment, but also the configurations of the plurality of embodiments can be partially combined with each other without any problem in the combination, as long as there is no particular problem in the combination. And the combinations not explicitly shown among the configurations described in the plurality of embodiments and modification examples are also considered to be disclosed by the following description.

[0069] In the example of FIG. 2, the semiconductor unit 20 functions as a DC-AC conversion unit that converts the input DC power into three-phase alternating current of a predetermined frequency. On the other hand, the semiconductor unit 20 may have a function as a DC-DC conversion unit that converts a DC voltage into DC voltages of different values. Alternatively, the semiconductor unit 20 may have both functions of the DC-AC conversion unit and the DC-DC conversion unit.

[0070] In the example of FIG. 1, there is one motor 3 to which the power conversion device 6 outputs power, but a plurality of motors may be power output targets. In that case, since the number of upper and lower arm circuits increases, the physical size of the semiconductor unit 20 in the stacking direction becomes larger.

[0071] In the first embodiment, the connection between the output terminals 70U, 70V, 70W and the output cable 3a is bolt fastening or welding. On the other hand, the output terminals 70U, 70V, 70W and the output cable 3a may be connected by a connector.

[0072] In the first embodiment, the lower arm bus bar 25N and the input bus bar 61N are separate metal members, and these bus bars are connected by bolts or welding. On the other hand, these bus bars may be integrally formed of one metal member. Similarly, the upper arm bus bar 25P and the input bus bar 61P may also be integrally formed of one metal member. Similarly, the output bus bars 71U, 71V, 71W and the neutral point bus bar 25O may also be integrally formed of one metal member.

[0073] Also, the input bus bar 61N and the input terminal 60N may be separately connected or integrally formed of one metal member. Similarly, the input bus bar 61P and the input terminal 60P may also be separately connected or integrally formed. Similarly, the output bus bars 71U, 71V, 71W and the output terminals 70U, 70V, 70W may also be separately connected or integrally formed.

[0074] In the above-described first embodiment, the cooler 21 has a double-sided cooling structure that contacts and cools both sides of the power card 24. In contrast, the cooler 21 may have a single-sided cooling structure that contacts and cools one side of the power card 24.

[0075] The output busbars 71U, 71V, 71W and the output terminal block 70 may be assembled to the current detection unit 40 and integrated into one component. Further, the upper arm busbar 25P and the lower arm busbar 25N may be assembled to the capacitor 30 and integrated into one component. Further, the input busbars 61P and 61N and the input terminal block 60 may be assembled to the capacitor 30 and integrated into one component.

Description of Reference Numerals

[0076] 6... Power conversion device 2 battery, 6 power conversion device, 21 cooler, 24 semiconductor module, 24N N terminal, 24O O terminal, 24P P terminal, 3 motor, 30 capacitor, 40 current detection unit, 60N, 60P input terminals, 61N, 61P input busbars, 70U, 70V, 70W output terminals, 71U, 71V, 71W output busbars, Ac projection range, Ain input side region, Aout output side region, VS virtual plane.

Claims

1. A plurality of semiconductor modules (24) each having a built-in semiconductor element and arranged in a predetermined stacking direction; a cooling section (20) having a metallic cooler (21) for cooling the plurality of semiconductor modules, an inlet pipe (22) for introducing a refrigerant into the cooler, and an outlet pipe (23) for discharging the refrigerant from the cooler; an input terminal (60P, 60N) electrically connected to an external battery (2) and receiving power from the battery; a capacitor (30) electrically connected in parallel to the plurality of semiconductor modules and the battery, and smoothing voltage pulsation of the power supplied from the input terminal; an input bus bar (61P, 61N) electrically connecting the capacitor and the input terminal; a current detection unit (40) for detecting the magnitude of an AC current output from the semiconductor module; an output terminal (70U, 70V, 70W) electrically connected to an external motor (3) and outputting the AC current to the motor; an output bus bar (71U, 71V, 71W) electrically connecting the current detection unit and the output terminal; the semiconductor module has terminals arranged in a row in a direction perpendicular to the stacking direction, the terminals including a P terminal (24P) electrically connected to a high potential side of the capacitor, an N terminal (24N) electrically connected to a low potential side of the capacitor, and an O terminal (24O) electrically connected to the current detection unit; Of the two regions partitioned by a virtual plane (VS) perpendicular to the direction in which the P terminals, the N terminals, and the O terminals are arranged, a region including the P terminals and the N terminals of a plurality of the semiconductor modules is defined as an input side region (Ain), and a region including the O terminals of a plurality of the semiconductor modules is defined as an output side region (Aout); the input terminals are arranged in the input side region together with the capacitor; The output terminals are disposed in the output side area together with the current detection unit, At least a part of the cooling unit is provided between the input bus bar and the output bus bar, the P terminal, the N terminal, and the O terminal extend in an extension direction perpendicular to both the stacking direction and the arrangement direction in the semiconductor module, The capacitor and the current detection unit are arranged on the semiconductor module in a direction perpendicular to the extension direction.

2. a high arm bus bar (25P) electrically connected to each of the high potential side of the capacitor, a high input bus bar (61P) which is the input bus bar on the high potential side, and the P terminal; a low arm bus bar (25N) electrically connected to each of the low potential side of the capacitor, a low input bus bar (61N) which is the input bus bar on the low potential side, and the N terminal; The power conversion device according to claim 1 .

3. The power conversion device according to claim 1 , wherein the output bus bars of at least two of three phases are arranged within a projection range in which the input bus bars are projected onto the cooling portion.

4. The power conversion device according to any one of claims 1 to 3, wherein at least one of the input bus bar on the high potential side and the input bus bar on the low potential side is arranged within a projection range in which the output bus bar is projected onto the cooling section.

5. The power conversion device according to any one of claims 1 to 4, wherein at least a portion of the cooler is provided between the input bus bar and the output bus bar.

6. The power conversion device according to any one of claims 1 to 5, wherein at least a portion of the inflow pipe and at least a portion of the outflow pipe are provided between the input bus bar and the output bus bar.

7. The power conversion device according to any one of claims 1 to 5, wherein the output terminals are arranged in a projection range (Ac) of the cooler in a direction in which the capacitor and the current detection unit are arranged and in which the P terminal, the N terminal, and the O terminal are arranged.

8. The power conversion device according to any one of claims 1 to 6, wherein the input terminals are arranged in a projection range (Ac) of the cooler in a direction in which the capacitor and the current detection unit are arranged and in which the P terminal, the N terminal, and the O terminal are arranged.

9. 8. The power conversion device according to claim 1, wherein the cooler is structured to come into contact with both sides of the semiconductor module to cool it.

10. The input bus bar is provided at a position away from the cooling portion toward the input terminal, The power conversion device according to any one of claims 1 to 8, wherein the output bus bar is provided at a position away from the cooling portion toward the output terminal.

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