Power conversion module

Abstract

To provide a power conversion module that does not malfunction.SOLUTION: A power conversion module provided on a vehicle driving device 100 includes an inverter 3 which supplies DC power from a battery provided on a vehicle to a driving motor of the vehicle and a cooling plate 60 through which a cooling fluid flows, in which a non-located area NM where no electrical component is located is provided on the opposite side of the inverter 3 sandwiching the cooling plate 60.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a power conversion module provided in a vehicle drive device. [Background technology]

[0002] In recent years, automobiles equipped with a motor as a driving source (such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), and fuel cell electric vehicles (FCEVs)) have become widespread. These automobiles are provided with a vehicle drive device that drives the motor and other components, and this vehicle drive device is equipped with a power conversion module having a plurality of electronic components.

[0003] Patent Document 1, cited below, describes a voltage conversion device as an example of such a power conversion module. This voltage conversion device includes a housing partitioned into a first space and a second space by a partition member, and a voltage conversion circuit that transforms and outputs the voltage of an input power. The first space houses a primary circuit of the voltage conversion circuit to which the voltage of the input power is applied, and the second space houses a secondary circuit of the voltage conversion circuit to which a voltage transformed from the voltage of the input power is applied. The primary circuit and the secondary circuit are electrically connected within the housing via an opening provided in the partition member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-61892 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the voltage conversion device described in Patent Document 1, the primary circuit and the secondary circuit of the voltage conversion circuit are respectively stored in separate spaces (first space and second space) separated by a partition member as described above. The primary circuit includes a rectifier that rectifies AC power from an external power source, a power factor correction unit that constitutes the voltage conversion circuit, an inverter, and a transformer, which are stored in the first space. On the other hand, the secondary circuit includes a DC / DC conversion unit that supplies power to the load, and a power conversion unit that energizes the motor, which are stored in the second space. The power conversion unit is provided facing the rectifier and the power factor correction unit across the partition member. A high voltage is applied to the power conversion unit, and a current with a large amplitude flows through it, so that noise is generated in the surroundings and the amount of heat generated is also large. For this reason, the rectifier and the power factor correction unit may malfunction due to the influence of noise and heat.

[0006] Therefore, there is a demand for a power conversion module that will not malfunction. [Means for solving the problem]

[0007] The characteristic configuration of the power conversion module of the present invention is that it is a power conversion module provided in a vehicle drive device, and comprises an inverter that energizes the vehicle's driving motor using DC power from a battery installed in the vehicle, and a cooling plate through which a cooling fluid flows, and on the opposite side of the inverter across the cooling plate, a non-placement area in which no electronic components are placed is provided.

[0008] With this characteristic configuration, not only can the cooling plate reduce heat from the inverter, but the cooling fluid flowing through the cooling plate can also attenuate noise from the transformer, reducing the impact on other electronic components. This makes it possible to eliminate (prevent) or reduce malfunctions of the power conversion module. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 illustrates a cooling circuit including a power conversion module. [Diagram 2] FIG. 2 is a block diagram showing a configuration of a power conversion module. [Diagram 3] FIG. 2 is a vertical cross-sectional view of the vehicle drive device. [Figure 4] 1A and 1B are diagrams showing the arrangement of substrates included in a power conversion module. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The power conversion module according to the present invention is provided in a vehicle drive device. The power conversion module 1 of the present embodiment will be described below. However, the power conversion module 1 is not limited to the following embodiment, and various modifications are possible without departing from the gist of the present invention.

[0011] FIG. 1 shows a cooling circuit A including a power conversion module 1. The cooling circuit A cools the power conversion module 1 with a cooling fluid. The cooling fluid is cooling water such as long-life coolant (LLC), insulating oil such as paraffin, or refrigerant such as hydrofluorocarbon (HFC) or hydrofluoroolefin (HFO). In this embodiment, it is preferable to use cooling water such as long-life coolant (LLC) or liquid with high electrical insulation such as a fluorine-based inert liquid, and a cooling liquid composed of cooling water or insulating oil may also be used. The cooling circuit A is mounted on a vehicle that charges a battery B1 (see FIG. 2) with external power.

[0012] The cooling circuit A includes the power conversion module 1, a water-cooled condenser 81, an oil cooler (an example of a "heat exchanger") 82, a water pump 83, a three-way valve 84, and a radiator 85. The cooling fluid is heated as it flows through the power conversion module 1. The cooling fluid flowing out of the power conversion module 1 is heated by heat exchange with the refrigerant in the water-cooled condenser 81, and then is further heated by heat exchange with the lubricant in the oil cooler 82. The cooling fluid is pumped out by the water pump 83, and the cooling circuit A is switched by the three-way valve 84 between a flow state in which the cooling fluid is sent to the radiator 85 and a flow state in which the cooling fluid bypasses the radiator 85. When the cooling fluid is sent to the radiator 85, the cooling fluid is cooled in the radiator 85 and flows back into the power conversion module 1. When the cooling fluid bypasses the radiator 85, the cooling fluid flows back into the power conversion module 1 in a heated state without being cooled.

[0013] Fig. 2 is a block diagram showing the configuration of the power conversion module 1. As shown in Fig. 2, the power conversion module 1 includes a power supply module 2, an inverter 3, and a control unit 4. The power supply module 2 includes an AC / DC conversion unit 10 and a converter 20. The converter 20 includes a first conversion unit 31, a second conversion unit 41, a third conversion unit 51, and a transformer T. The control unit 4 is constructed of hardware or software, or both, with a CPU as a core member, in order to perform processing related to the control of the power conversion module 1.

[0014] The inverter 3 energizes the vehicle's driving motor M with DC power from a battery B1 mounted on the vehicle. The battery B1 is a battery that stores power that serves as a power source for the vehicle. The inverter 3 has a plurality of legs connected in parallel with each other, and each of the plurality of legs has a high-side switching element and a low-side switching element connected in series with each other. These switching elements can be configured using, for example, n-type MOS-FETs.

[0015] The AC / DC converter 10 converts AC power from the outside into DC power. The outside is a power source outside the power conversion module 1, different from the battery B1 mounted on the vehicle. The AC power refers to power composed of an AC voltage whose voltage value oscillates at a predetermined cycle. Specifically, the AC voltage oscillates at a commercial frequency (e.g., 50 Hz or 60 Hz) and corresponds to an AC voltage of 200 V (effective value) taken from a commercial power source supplied in a single-phase three-wire system. The DC power refers to power composed of a DC voltage that has a constant voltage value (excluding ripple voltage) with respect to a reference voltage. The AC / DC converter 10 converts the AC power composed of such an AC voltage into DC power composed of a DC voltage.

[0016] The AC / DC converter 10 has multiple legs connected in parallel, and each of the multiple legs has a high-side switching element and a low-side switching element connected in series. These switching elements can also be configured using, for example, n-type MOS-FETs. The AC / DC converter 10 is connected to the charging port 5 via a relay Ry.

[0017] The converter 20 converts the DC power converted by the AC / DC conversion unit 10 into DC power capable of charging the battery B1. As described above, the converter 20 has the first conversion unit 31, the second conversion unit 41, the third conversion unit 51, and the transformer T. In this embodiment, the transformer T is an insulated multi-port transformer having a primary winding, a secondary winding, and a tertiary winding.

[0018] The first conversion unit 31 inputs DC power from the AC / DC conversion unit 10 to a primary winding of the transformer T. The first conversion unit 31 has a plurality of legs connected in parallel with each other, and each of the plurality of legs has a high-side switching element and a low-side switching element connected in series with each other. These switching elements can also be configured using n-type MOS-FETs.

[0019] A current (alternating current) according to the turn ratio between the primary winding and the secondary winding flows through the secondary winding, and a voltage (alternating voltage) according to the turn ratio between the primary winding and the secondary winding is generated. The secondary winding is connected to the second conversion unit 41.

[0020] The second conversion unit 41 rectifies the AC power from the secondary winding of the transformer T and converts it into DC power that can charge the battery B1. The second conversion unit 41 has a plurality of legs connected in parallel with each other, and each of the plurality of legs has a high-side switching element and a low-side switching element connected in series with each other. These switching elements can also be configured using n-type MOS-FETs.

[0021] A current (alternating current) according to the turn ratio between the primary winding and the tertiary winding flows through the tertiary winding, and a voltage (alternating voltage) according to the turn ratio between the primary winding and the tertiary winding is generated. The third conversion unit 51 rectifies the voltage (alternating voltage) generated in the tertiary winding and converts it into DC power composed of a DC voltage with a lower voltage value (for example, 12 V) than the voltage value of the DC voltage output from the second conversion unit 41.

[0022] The third conversion unit 51 rectifies the AC power from the tertiary winding of the transformer T and converts it into DC power that can charge the battery B2. The third conversion unit 51 can be configured to convert the AC power into DC power by synchronous rectification using, for example, two switching elements. In this case, these switching elements can also be n-type MOS-FETs.

[0023] Respective gate terminals of the switching elements included in the inverter 3, the AC / DC conversion unit 10, and the converter 20 are connected to the control unit 4. The control unit 4 transmits control signals to the respective switching elements to drive the switching elements.

[0024] Here, the relay Ry switches the conversion operation of the converter 20. The conversion operation of the converter 20 corresponds to the operation of converting AC power to DC power and the operation of converting DC power to AC power, both of which are performed by the converter 20.

[0025] In this embodiment, the converter 20 switches, via the relay Ry, between a state in which the converter 20 converts the DC power from the AC / DC conversion unit 10 into DC power composed of a DC voltage of a predetermined first voltage value, and the power supply module 2 is used as a charger, and a state in which the converter 20 converts the DC power from the battery B1 into DC power composed of a DC voltage of a predetermined second voltage value, and the power supply module 2 is used as an AC power output device.

[0026] Relay Ry switches between a state in which AC power supplied from charging port 5 is input to AC / DC conversion unit 10 and a state in which AC power generated based on DC power from battery B1 (for example, AC power having a voltage value of 100 V effective value) can be extracted from outlet 6.

[0027] Fig. 3 is a vertical cross-sectional view of the vehicle drive device 100. Fig. 4 is a diagram showing the arrangement of switching substrates SS (a general term for a first substrate SS1, a second substrate SS2, and a third substrate SS3) included in the power conversion module 1.

[0028] In this embodiment, the switching elements of the AC / DC converter 10 and the first converter 31 are mounted on a first substrate SS1. Diodes are also mounted on the first substrate SS1 across the source terminals and drain terminals of the switching elements mounted on the first substrate SS1. The switching elements of the second converter 41 are mounted on a second substrate SS2. Diodes are also mounted on the second substrate SS2 across the source terminals and drain terminals of the switching elements mounted on the second substrate SS2. The switching elements of the third converter 51 are mounted on a fourth substrate SS4. Diodes are also mounted on the fourth substrate SS4 across the source terminals and drain terminals of the switching elements mounted on the fourth substrate SS4.

[0029] The switching elements of the inverter 3 are mounted on a third substrate SS3. Diodes are also mounted on the third substrate SS3, each of which is provided across a source terminal and a drain terminal of the switching elements mounted on the third substrate SS3. The control unit 4 is mounted on a control substrate 4S. The control unit 4 drives each of the switching elements based on a control signal. Therefore, the control substrate 4S is connected to each of the first substrate SS1, the second substrate SS2, and the third substrate SS3 via a control line that transmits a control signal.

[0030] The first board SS1, the second board SS2, the third board SS3, and the control board 4S are accommodated in a housing 100H of the vehicle drive device 100. The vehicle drive device 100 has a first space 111. The first board SS1, the second board SS2, and the third board SS3 are accommodated in the first space 111 in a parallel orientation. Hereinafter, the direction perpendicular to the plate surface of the first board SS1 is referred to as the "vertical direction". In addition, in FIG. 3, the direction in which the control board 4S is viewed from the first board SS1, the second board SS2, and the third board SS3 along the vertical direction is referred to as the "upper direction", "upper side", etc., and the direction in which the first board SS1, the second board SS2, and the third board SS3 are viewed from the control board 4S is referred to as the "lower direction", "lower side", etc.

[0031] The housing 100H has a first space 111 and a second space 112 and a third space 113 separated from each other. The second space 112 and the third space 113 are located below the first space 111. A motor M driven by an inverter 3 is accommodated in the second space 112, and a gear mechanism 87 that reduces the rotation of the motor M and outputs it is accommodated in the third space 113. The housing 100H has an opening Ha above the first space 111, and the first board SS1, the second board SS2, the third board SS3, the control board 4S, and a cooling plate 60 (described later) are accommodated in the first space 111 from the opening Ha.

[0032] The opening Ha is closed by a lid 114, and the first space 111 is a closed space. The second space 112 is a closed space, closed by a motor cover 115 that accommodates the motor M from the side and is fastened by a bolt 115A. A motor shaft Ma extends from the motor M on both sides along the rotation axis, and one of the motor shafts Ma penetrates the motor cover 115 and is exposed to the outside of the housing 100H. The other motor shaft Ma penetrates to the third space 113. The third space 113 is a closed space, closed by a gear cover 116 that accommodates a gear mechanism 87 from the side and is fastened by a bolt 116A. The other motor shaft Ma extending from the second space 112 is connected to the gear mechanism 87, and the rotation of the motor M is input via the motor shaft Ma. The gear mechanism 87 reduces the rotation of the motor M and outputs it from the gear shaft 87a. The gear shaft 87a passes through the gear cover 116 and is exposed to the outside of the housing 100H.

[0033] As shown in FIG. 3, the multiple switching boards SS are provided at the same height in the housing 100H of the vehicle drive device 100. In this embodiment, the multiple switching boards SS are a first board SS1, a second board SS2, and a third board SS3. These switching boards SS (the first board SS1, the second board SS2, and the third board SS3) are provided in the housing 100H of the vehicle drive device 100. The positions at the same height mean the positions at the same height in the vertical direction. Therefore, the first board SS1, the second board SS2, and the third board SS3 are provided at the same height in the vertical direction. In this embodiment, as shown in FIG. 4, the first board SS1, the second board SS2, and the third board SS3 are provided side by side along the width direction of the vehicle.

[0034] Returning to FIG. 3, the control board 4S is supported on the upper surface of a metallic support 61 having a C-shaped cross section. The support 61 is fixed to a cooling plate 60 by bolts 61A. The first board SS1, the second board SS2, and the third board SS3 are disposed below the support 61. The control board 4S is disposed so as to overlap with the second board SS2 and the third board SS3 when viewed in the vertical direction (vertical view). A harness 142 is used to connect the second board SS2 and the control board 4S, and to connect the third board SS3 and the control board 4S. This makes it easy to assemble the control board 4S to the second board SS2 and the third board SS3.

[0035] The first board SS1 and the control board 4S are connected to each other using a harness 143. The first board SS1 and the second board SS2 are connected to each other by a harness (not shown).

[0036] As described above, the first substrate SS1 is mounted with the capacitor 11. Also, on the upper side of the cooling plate 60, connection terminals (not shown) are attached which are connected to the capacitor 42 and the positive and negative electrodes of the battery B1.

[0037] Further, a through hole 60H is formed in the cooling plate 60, and via a conductor 77 inserted into this through hole 60H, the reactor coil L1 and the first substrate SS1 are connected, and the transformer T and the second substrate SS2 are connected.

[0038] 3, a cooling plate 60 through which a cooling fluid flows is provided inside the housing 100H of the vehicle drive device 100. The cooling plate 60 is formed in a plate shape, and the first substrate SS1, the second substrate SS2, and the third substrate SS3 are provided in parallel to and adjacent to the cooling plate 60. In this embodiment, these substrates are provided above the cooling plate 60. This makes it possible to cool the switching elements mounted on the first substrate SS1, the second substrate SS2, and the third substrate SS3 by the cooling fluid.

[0039] In this embodiment, the first substrate SS1, the second substrate SS2, and the third substrate SS3 are provided on the opposite side of the transformer T across the cooling plate 60. That is, the transformer T is provided below the cooling plate 60. In this embodiment, the first substrate SS1 and the second substrate SS2 are provided spaced apart from each other along the cooling plate 60. When viewed along a direction perpendicular to the mounting surfaces of the first substrate SS1 and the second substrate SS2, the transformer T is provided between the first substrate SS1 and the second substrate SS2. This prevents noise caused by the magnetic flux emitted from the transformer T from being superimposed on the control signals that drive the switching elements mounted on the first substrate SS1 and the second substrate SS2, and suppresses the effects of noise.

[0040] In this embodiment, the inverter 3 is provided adjacent to the inner wall HI of the housing 100H of the vehicle drive device 100. As described above, the switching elements of the inverter 3 are mounted on the third board SS3, and the third board SS3 is provided above the cooling plate 60. The inner wall HI of the housing 100H of the vehicle drive device 100 is a wall portion facing the space in which the third board SS3 is accommodated. Therefore, the third board SS3 on which the switching elements of the inverter 3 are mounted is provided adjacent to a wall portion that forms the space in which the third board SS3 is accommodated in the housing 100H of the vehicle drive device 100.

[0041] 3, a non-placement area NM where no electronic components are placed is provided on the opposite side of the inverter 3 across the cooling plate 60. As described above, the third substrate SS3 on which the switching elements of the inverter 3 are mounted is provided above the cooling plate 60. The opposite side of the inverter 3 across the cooling plate 60 means the area below the third substrate SS3 in the housing 100H of the vehicle drive device 100, and further below the cooling plate 60. The electronic components include not only active components such as the above-mentioned switching elements, diodes, and integrated circuits, but also passive components such as resistors and capacitors. Therefore, a non-placement area NM where active components such as switching elements, diodes, and integrated circuits, and passive components such as resistors and capacitors are not placed is provided below the third substrate SS3 in the housing 100H of the vehicle drive device 100, and further below the cooling plate 60.

[0042] In this embodiment, the oil cooler 82 that exchanges heat between a cooling fluid and oil circulating in the vehicle drive device 100 is provided in the non-placement area NM. As described above, the cooling fluid flows through the cooling plate 60. The oil circulating in the vehicle drive device 100 is lubricating oil supplied to the traveling motor M and the gear mechanism 87. The oil cooler 82 is not provided with electronic components as described above, and is provided in the non-placement area NM.

[0043] In this embodiment, the cooling plate 60 has a conductive portion 62 made of metal. In the example of Fig. 4, the conductive portion 62 is provided over the entire upper and lower surfaces of the cooling plate 60 in a plan view of the cooling plate 60. However, the conductive portion 62 may be provided on a part of the upper and lower surfaces of the cooling plate 60. The conductive portion 62 may be provided on at least one of the upper and lower surfaces of the cooling plate 60. By providing the conductive portion 62 on the cooling plate 60 in this manner, it is possible to increase the heat exchange efficiency of the cooling plate 60.

[0044] It is preferable to ground the conductive portion 62. This makes it possible to prevent the control signals for driving the switching elements, which are transmitted from the control substrate 4S to each of the first substrate SS1, the second substrate SS2, the third substrate SS3, and the fourth substrate SS4, from being disturbed by external noise.

[0045] Other embodiments Next, other embodiments of the power conversion module 1 will be described.

[0046] In the above embodiment, the inverter 3 has been described as being provided close to the inner wall HI of the housing 100H of the vehicle drive device 100. However, the inverter 3 may be provided in the center of the housing 100H away from the inner wall HI of the housing 100H of the vehicle drive device 100.

[0047] In the above embodiment, it has been described that the non-placement area NM is provided with the oil cooler 82 that performs heat exchange between the cooling fluid and the oil circulating in the vehicle drive device 100. However, it is also possible to configure the non-placement area NM without providing the oil cooler 82.

[0048] In the above embodiment, the cooling plate 60 has been described as having a fluid flowing therethrough, but it may be configured to have only the conductive portion 62 without having a fluid flow therethrough.

[0049] [Summary of the above embodiment] The above-described power conversion module 1 will now be outlined.

[0050] (1) The power conversion module 1 provided in the vehicle driving device 100 includes an inverter 3 that supplies DC power from a battery B1 mounted on the vehicle to the vehicle's driving motor M, and a cooling plate 60 through which a cooling fluid flows. On the opposite side of the inverter 3 across the cooling plate 60, a non-placement area NM is provided where no electronic components are placed.

[0051] According to this configuration, not only does the cooling plate 60 reduce heat from the inverter 3, but the cooling fluid flowing through the cooling plate 60 attenuates noise from the transformer T, making it possible to reduce the impact on other electronic components. Therefore, it is possible to eliminate (prevent) or reduce malfunction of the power conversion module 1.

[0052] (2) It is preferable that the inverter 3 described in (1) be provided in the vicinity of the inner wall HI of the housing 100H of the vehicle drive device 100.

[0053] According to this configuration, by disposing the inverter 3 at an end portion within the housing 100H, it is possible to further reduce the influence on other electronic components.

[0054] (3) It is preferable that the power conversion module 1 described in (1) or (2) has a heat exchanger (e.g., an oil cooler 82) in the non-placement area NM for exchanging heat between a cooling fluid and oil circulating in the vehicle drive device 100.

[0055] According to this configuration, the oil cooler 82, which is not affected by noise from the inverter 3, can be arranged on the opposite side of the cooling plate 60 from the inverter 3, where no electronic components are arranged. Therefore, it is possible to increase the accommodation efficiency of the vehicle drive device 100 within the housing 100H. [Industrial Applicability]

[0056] The technology disclosed herein can be used in a power conversion module provided in a vehicle drive device. [Explanation of symbols]

[0057] 1: power conversion module, 3: inverter, 60: cooling plate, 82: oil cooler (heat exchanger), 100: vehicle drive unit, 100H: housing, B1: battery, HI: inner wall, M: driving motor, NM: non-placement area

Claims

1. A power conversion module provided in a vehicle drive device, an inverter that energizes a vehicle's drive motor using DC power from a battery mounted on the vehicle; a cooling plate through which a cooling fluid flows; A power conversion module in which a non-placement area in which no electronic components are placed is provided on the opposite side of the inverter with the cooling plate interposed therebetween.

2. The power conversion module according to claim 1 , wherein the inverter is provided adjacent to an inner wall of a housing of the vehicle drive device.

3. The power conversion module according to claim 1 or 2, wherein a heat exchanger that exchanges heat between the cooling fluid and oil circulating in the vehicle drive device is provided in the non-placement area.

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