Electric power conversion device

Abstract

To reduce the size of an electric power conversion device while considering heat dissipation.SOLUTION: A disclosed electric power conversion device includes a housing and a power factor improvement circuit module. The housing has a flow path running within one plane formed inside. The power factor improvement circuit module has a cooling plate, a power semiconductor, an electrolytic capacitor, and a resin mold. The cooling plate has thermal conductivity and is formed into a flat plate. The power semiconductor has a heat dissipation surface facing a first main surface of the cooling plate, which is fixed to the first main surface so as to facilitate heat exchange and is electrically connected to a drive substrate. The electrolytic capacitor is placed on the opposite side of the cooling plate, opposite to the power semiconductor, and is electrically connected to the drive substrate. The resin mold is fixed to the first main surface of the cooling plate and is interposed at least between the power semiconductor and the electrolytic capacitor, determining the position of the power semiconductor. A second main surface of the cooling plate, which is the backside of the first main surface, is thermally connected to the housing.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a power conversion device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there is a demand for miniaturization of power conversion devices such as chargers mounted on electric vehicles and the like due to limitations on mounting space, for example.

[0003] For example, Patent Document 1 discloses a technology for reducing the size of a power conversion device as a whole by incorporating a power semiconductor, a smoothing capacitor, and a gate drive board. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6749428 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when converting large currents and high voltages, power semiconductors experience significant power loss and generate significant heat. Furthermore, heat generated by power semiconductors also increases the impact of heat on the surrounding area, potentially resulting in adverse effects such as thermal degradation of capacitors. In this situation, when using a liquid-cooling system as a heat dissipation method, for example, when a horizontal flow path is branched into a vertical flow path to match the layout of the power semiconductors, the refrigerant may stagnate within the flow path, preventing efficient heat dissipation. Therefore, there is room for improvement in heat dissipation from power semiconductors.

[0006] One of the problems that the present disclosure aims to solve is to reduce the size of a power conversion device while taking heat dissipation into consideration. [Means for solving the problem]

[0007] The power conversion device according to the present disclosure includes a housing and a power factor correction circuit module. The housing has a flow path formed therein that runs within one plane. The power factor correction circuit module is detachably fixed to the housing. The power factor correction circuit module includes a cooling plate, a power semiconductor, an electrolytic capacitor, and a resin mold. The cooling plate is thermally conductive and formed in a flat plate shape. The power semiconductor has a heat dissipation surface facing a first main surface of the cooling plate, is fixed to the first main surface to be able to exchange heat with the cooling plate, and is electrically connected to a drive substrate. The electrolytic capacitor is disposed on the drive substrate side opposite the cooling plate with respect to the power semiconductor, and is electrically connected to the drive substrate. The resin mold is fixed to the first main surface of the cooling plate, determines the position of the power semiconductor, and is interposed at least between the power semiconductor and the electrolytic capacitor. When the power factor correction circuit module is fixed to the housing, a second main surface of the cooling plate, which is the opposite side of the first main surface, is thermally connected to the housing. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to reduce the size of a power conversion device by taking heat dissipation into consideration. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a charging system including a power conversion device equipped with a power factor correction circuit module according to an embodiment. [Figure 2] FIG. 2 is a perspective view showing an example of the configuration of the power factor correction circuit module of FIG. [Figure 3] FIG. 3 is a cross-sectional view showing an example of the configuration of the power factor correction circuit module of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of a power factor correction circuit structure, a power factor correction circuit module, a power conversion device, a vehicle, and a charging system according to the present disclosure will be described with reference to the drawings.

[0011] In the description of the present disclosure, components having the same or substantially the same functions as those described above with respect to the previously-mentioned drawings may be given the same reference numerals, and descriptions thereof may be omitted as appropriate. Furthermore, even when the same or substantially the same parts are shown, the dimensions and proportions may be different depending on the drawing. Furthermore, for example, in order to ensure the visibility of the drawings, reference numerals may be given to only the main components in the description of each drawing, and reference numerals may not be given to components having the same or substantially the same functions as those described above with respect to the previously-mentioned drawings.

[0012] In the description of the present disclosure, components having the same or substantially the same functions may be distinguished by adding an alphanumeric character to the end of the reference symbol. Alternatively, when multiple components having the same or substantially the same functions are not distinguished, they may be collectively described by omitting the alphanumeric character at the end of the reference symbol.

[0013] Fig. 1 is a diagram showing an example of the configuration of a charging system 1 according to an embodiment. As shown in Fig. 1, the charging system 1 includes an AC power supply 11, a load 13, and a power conversion device 2. Fig. 1 illustrates a case where a three-phase AC power supply (external power supply) and a battery are connected to the power conversion device 2 as the AC power supply 11 and the load 13.

[0014] As an example, the power conversion device 2 according to the embodiment may be mounted on a vehicle as, for example, an on-board charger. For example, the power conversion device 2 may be an on-board charger that converts AC power supplied from an external single-phase or three-phase AC power source 11 into DC power and supplies the converted DC power to a load 13 mounted on the vehicle. This load 13 may be, for example, a battery, an inverter, a motor, or various electrical components. In other words, the power conversion device 2 according to the embodiment may be realized as an on-board charger that converts AC power from the external AC power source 11 into DC power and supplies power to a load 13 such as a vehicle battery that is charged using the DC power.

[0015] The vehicle may be any type of moving body configured to be driven or to drive its accessories (electrical components) using power from a battery, such as a passenger car, freight vehicle, van, motorcycle, or electric kick scooter. Examples of such electrical components include a navigation system, an audio system, an air conditioner, a power window, a defogger, an ECU (Electronic Control Unit), a GPS (Global Positioning System) module, and an on-board camera. The vehicle battery may be any battery capable of storing power for driving the traction motor (main motor) and electrical components mounted on the vehicle, and any battery, such as a lithium-ion battery, a nickel-metal hydride battery, or an all-solid-state battery, may be used. The power conversion device 2 according to the embodiment may be installed not only in vehicles but also in aircraft, amusement facilities, uninterruptible power supplies, and the like.

[0016] The AC power supply 11 is any external power supply, such as a power supply installed in a quick charging facility or a commercial power supply. The AC power supply 11 is not limited to a single-phase AC power supply or a three-phase AC power supply (multiple-phase AC power supply), and a two-phase AC power supply (multiple-phase AC power supply) may also be used. In this embodiment, a case where any single-phase or three-phase AC power supply 11 can be used as the AC power supply 11 that supplies AC power to the power conversion device 2 is exemplified. That is, in this embodiment, a power conversion device 2 configured to be operable with AC power input from either a single-phase AC power supply 11 or a three-phase AC power supply 11 is exemplified.

[0017] As shown in FIG. 1 , the power conversion device 2 is electrically connected to an AC power supply 11 via any of a plurality of power supply lines L1 to L3, N. It is assumed that each of the plurality of power supply lines L1 to L3, N is electrically connected to an input terminal of the power conversion device 2. As an example, the power supply line L1 is an electric wire through which a single-phase current from the single-phase AC power supply 11 flows. As an example, the power supply line L1 is an electric wire through which, for example, a U-phase (first phase) current from a three-phase AC power supply 9b flows. As an example, the power supply line L2 is an electric wire that is not electrically connected to the single-phase AC power supply 11. As an example, the power supply line L2 is an electric wire through which, for example, a V-phase (second phase) current from the three-phase AC power supply 11 flows. As an example, the power supply line L3 is an electric wire that is not electrically connected to the single-phase AC power supply 11. As an example, the power supply line L3 is an electric wire through which, for example, a W-phase (third phase) current from the three-phase AC power supply 11 flows. As an example, the power supply line N is a neutral line, and is electrically connected to a single-phase or three-phase AC power supply 11 and to a ground potential.

[0018] As shown in FIG. 1, the power conversion device 2 includes a noise filter 4, a power factor correction (PFC) circuit 5, and a DC-DC conversion circuit 6.

[0019] The noise filter 4 suppresses (removes) noise from entering the power conversion device 2 from the AC power supply 11 and from leaking noise from the power conversion device 2 to the AC power supply 11. The noise filter 4 is electrically connected to the input terminal of the power conversion device 2 and the power factor correction circuit 5 via a plurality of power supply lines L1 to L3, N. In the example of FIG. 1, the noise filter 4 has a plurality of coils provided on each of the plurality of power supply lines L1 to L3, N. Each of the plurality of coils is, for example, a common mode choke coil or a normal mode choke coil. In addition, a switch is provided in parallel with the coil provided on the power supply line N, which short-circuits between the input terminal of the power conversion device 2 and the power factor correction circuit 5 when turned on. This switch operates under the control of, for example, a control circuit (not shown) of the power conversion device 2.

[0020] In the noise filter 4, a plurality of X capacitors may be provided between each coil and the input terminal of the power conversion device 2. The plurality of X capacitors are electrically connected between each of the power supply lines L1 to L3 and the power supply line N (between the lines).

[0021] Note that a surge protection resistor may be provided on each of the power supply lines L1 to L3, for example, in the subsequent stage of the noise filter 4. The surge protection resistor is an inrush current prevention element such as a thermal fuse resistor, cement resistor, or thermistor, and prevents an inrush current from flowing to the power factor correction circuit 5.

[0022] The power factor correction circuit 5 rectifies and smoothes the AC voltage from the AC power supply 11 to generate a DC voltage. As shown in FIG. 1, the power factor correction circuit 5 is electrically connected to the noise filter 4 and the DC-DC conversion circuit 6. The power factor correction circuit 5 has high-side MOSFETs 51a, 51c, 51e, and 51g, low-side MOSFETs 51b, 51d, 51f, and 51h, and electrolytic capacitors 53a and 53b. The MOSFETs 51a to 51h are an example of a plurality of power semiconductors of the power conversion device 2.

[0023] The MOSFETs 51 rectify the AC voltage from the AC power supply 11. Each MOSFET 51 has a simplified equivalent circuit formed using, for example, a switch, a capacitor, and a diode, and operates in response to a control signal from a control circuit (not shown) of the power conversion device 2. For example, in the simplified equivalent circuit, the switch, the capacitor, and the diode are electrically connected in parallel. For example, in the high-side MOSFET 51, the anode and cathode of the diode are electrically connected to the input side (the AC power supply 11 side) and the output side (the load 13 side) of each MOSFET 51, respectively. On the other hand, in the low-side MOSFET 51, the anode and cathode of the diode are electrically connected to the output side and the input side of each MOSFET 51, respectively. In each MOSFET 51, the switch is turned on / off at a timing corresponding to a control signal from the control circuit (not shown) of the power conversion device 2, thereby switching between on / off and disconnection. In each MOSFET 51, charge from the AC power supply is accumulated in the capacitor during a period when the switch is off (disconnected), generating a potential difference between the input and output terminals. In this embodiment, turning on / off this internal switch is expressed as turning on / off the MOSFET 51.

[0024] The input and output sides of each high-side MOSFET 51 are electrically connected to the coil of the noise filter 4 and the input side of each high-side MOSFET 61 of the DC-DC conversion circuit 6. The input and output sides of each low-side MOSFET 51 are electrically connected to the coil of the noise filter 4 and the input side of each low-side MOSFET 61 of the DC-DC conversion circuit 6.

[0025] The MOSFETs 51a and 51b are an example of a pair of power semiconductors related to the power supply line L1, i.e., corresponding to a specific phase of the multiple phases of the AC power supply 11. Specifically, the MOSFETs 51a and 51b rectify a single-phase current from the single-phase AC power supply 11 flowing through the power supply line L1, or, for example, a U-phase (first phase) current from the three-phase AC power supply 11. The MOSFETs 51c and 51d are an example of a pair of power semiconductors related to the power supply line L2, i.e., corresponding to another phase of the specific phase of the multiple phases of the AC power supply 11. Specifically, the MOSFETs 51c and 51d rectify a single-phase current from the single-phase AC power supply 11 flowing through the power supply line L2, or, for example, a V-phase (second phase) current from the three-phase AC power supply 11. The MOSFETs 51e and 51f are an example of a pair of power semiconductors related to the power supply line L3, i.e., corresponding to another phase of the specific phase of the multiple phases of the AC power supply 11. Specifically, the MOSFETs 51e and 51f rectify a single-phase current from the single-phase AC power supply 11 flowing through the power supply line L3, or, for example, a W-phase (third-phase) current from the three-phase AC power supply 11. The MOSFETs 51g and 51h are an example of a pair of power semiconductors related to the power supply line N, i.e., corresponding to the neutral line. Specifically, the MOSFETs 51g and 51h form an electric path for returning the single-phase current flowing through the power supply lines L1 to L3 from the single-phase AC power supply 11 to the AC power supply 11 side.

[0026] The electrolytic capacitor 53 smoothes the current rectified by the MOSFET 51. The electrolytic capacitor 53 is an output capacitor of the power factor correction circuit 5. The electrolytic capacitor 53 can also be expressed as an input capacitor of the DC-DC conversion circuit 6. FIG. 1 illustrates electrolytic capacitors 53a and 53b as examples of the electrolytic capacitor 53. The electrolytic capacitors 53a and 53b are electrically connected between the output side (load 13 side) of the high-side MOSFET 51 and the output side (load 13 side) of the low-side MOSFET 51. The electrolytic capacitors 53a and 53b may be realized by one electrolytic capacitor or by three or more electrolytic capacitors. For example, FIG. 2 illustrates a case where eight electrolytic capacitors 53 are used.

[0027] The DC-DC conversion circuit 6 converts the DC voltage generated by the power factor correction circuit 5 back into an AC voltage, and then rectifies and smooths the AC voltage to generate a DC voltage of a desired set voltage. As shown in FIG. 1 , the DC-DC conversion circuit 6 is electrically connected to the power factor correction circuit 5 and the output terminal of the power conversion device 2. The DC-DC conversion circuit 6 has primary-side MOSFETs 61a to 61d, a primary-side coil 63, a transformer 73, secondary-side MOSFETs 81a to 81d, a secondary-side coil 83, and an output capacitor 85. The primary-side coil 63 and the secondary-side coil 83 may each be substituted by a leakage inductance of the transformer 73. The primary-side MOSFETs 61a to 61d are an example of a plurality of power semiconductors of the power conversion device 2.

[0028] The primary-side MOSFETs 61a to 61d and the coil 63 convert a DC voltage from the electrolytic capacitor 53 serving as an input capacitor into an AC voltage through the switching operation of the MOSFET 61 under the control of a control circuit (not shown) of the power conversion device 2. In other words, the primary-side MOSFETs 61a to 61d and the coil 63 constitute a DC-AC inverter circuit. A simplified equivalent circuit of each MOSFET 61 has a configuration similar to that of each MOSFET 51 of the power factor correction circuit 5, for example. In the high-side MOSFET 61, the anode and cathode of the diode are electrically connected to the output side (load 13 side) and input side (AC power supply 11 side) of each MOSFET 61, respectively. On the other hand, in the low-side MOSFET 61, the anode and cathode of the diode are electrically connected to the input side and output side of each MOSFET 61, respectively.

[0029] The input side of each high-side MOSFET 61 is electrically connected to the output side of each high-side MOSFET 51 of the power factor correction circuit 5. The input side of each low-side MOSFET 61 is electrically connected to the output side of each low-side MOSFET 51 of the power factor correction circuit 5. The output sides of the MOSFETs 61a and 61b are electrically connected to one end of the primary side of the transformer 73 via the coil 63. The output sides of the MOSFETs 61c and 61d are electrically connected to the other end of the primary side of the transformer 73, i.e., the side opposite to the coil 63.

[0030] The transformer 73 is a transformer that transfers the energy of the single-phase AC voltage generated by the MOSFETs 61a to 61d and the coil 63 on the primary side to the secondary side.

[0031] The secondary-side MOSFETs 81a to 81d and coil 83 rectify the single-phase AC voltage transmitted by the transformer 73 through the switching operation of the MOSFETs 81 under the control of a control circuit (not shown) of the power conversion device 2. A simplified equivalent circuit of each MOSFET 81 has a configuration similar to that of, for example, each MOSFET 51 of the power factor correction circuit 5. The anode and cathode of the diode in the high-side MOSFET 81 are electrically connected to the input side (AC power supply 11 side) and output side (load 13 side) of each MOSFET 61, respectively. On the other hand, the anode and cathode of the diode in the low-side MOSFET 81 are electrically connected to the output side and input side of each MOSFET 81, respectively.

[0032] The input sides of the MOSFETs 81a and 81b are electrically connected via a coil 83 to one end of the secondary side of the transformer 73, which is one end of the same polarity as the one end of the primary side to which the coil 63 is connected in the example of FIG. 1. The output sides of the MOSFETs 81c and 81d are electrically connected to the other end of the secondary side of the transformer 73, i.e., the side opposite to the coil 83. The output sides of the high-side and low-side MOSFETs 81 are electrically connected to a pair of output terminals of the power conversion device 2.

[0033] The output capacitor 85 smoothes the current rectified by the MOSFET 81. The output capacitor 85 is electrically connected between the output side (load 13 side) of the high-side MOSFET 81 and the output side (load 13 side) of the low-side MOSFET 81. In other words, the output capacitor 85 is electrically connected between a pair of output terminals of the power conversion device 2.

[0034] The control circuit (not shown) of the power conversion device 2 may have, for example, at least one processor and at least one memory, and may be configured as hardware using a normal computer. For example, a CPU (Central Processing Unit) may be used as this processor. The processor executes programs, for example, to comprehensively control the operation of the control circuit and realize various functions of the control circuit. For example, the processor may load programs stored in a ROM (Read Only Memory) or the like into a RAM (Random Access Memory) and execute the loaded programs to realize the various functions of the control circuit. Alternatively, some or all of the functions may be realized by dedicated hardware circuits (such as semiconductor integrated circuits).

[0035] The control circuit of the power conversion device 2 may be realized by a computer such as an ECU (Electronic Control Unit) provided inside the vehicle, a DCU (Domain Control Unit) such as a CDC (Cockpit Domain Controller) integrating multiple ECUs, or an OBU (On Board Unit).The control circuit may transmit and receive information to and from other ECUs mounted on the vehicle or an external power supply (AC power supply 11) connected to the vehicle via an in-vehicle network including a CAN (Controller Area Network), Ethernet (registered trademark), or USB (Universal Serial Bus (registered trademark)) within the vehicle, or may communicate with an information processing device outside the vehicle via a network such as the Internet.

[0036] 1, the power factor correction circuit 5 and the MOSFET 61 of the DC-DC conversion circuit 6 constitute a power factor correction circuit module 3 according to the embodiment. That is, the power conversion device 2 according to the embodiment is equipped with the power factor correction circuit module 3. Note that the power factor correction circuit module 3 may include other circuit components, such as a noise filter 4 and a coil 63.

[0037] Here, the power factor correction circuit structure of the power factor correction circuit module 3 according to the present disclosure will be described in detail with reference to the drawings.

[0038] FIG. 2 is a perspective view showing an example of the configuration (power factor correction circuit structure) of the power factor correction circuit module 3 of FIG. 1. FIG. 2 shows the appearance of the power factor correction circuit module 3 of the power conversion device 2 and its vicinity. FIG. 3 is a cross-sectional view showing an example of the configuration (power factor correction circuit structure) of the power factor correction circuit module 3 of FIG. 1. FIG. 3 shows a cross-section of the power factor correction circuit module 3 and its vicinity, viewed from the X+ side along a YZ plane passing through a plurality of fixing members 39c provided on the X+ side of the relay board 32b of FIG. 2. Note that in FIGS. 2 and 3, some or all of the other components of the power conversion device 2 are omitted from the illustration.

[0039] 2 and 3, the power factor correction circuit module 3 is disposed above (on the Z+ side of) the housing 21 of the power conversion device 2. As shown in Fig. 2, the power factor correction circuit module 3 is detachably fixed onto the housing 21 by a fixing member 39e such as a screw.

[0040] 2 and 3, a drive board 31 is disposed above (on the Z+ side of) the power factor correction circuit module 3. The drive board 31 is the main board of the power conversion device 2. Each component of the power conversion device 2 is electrically connected to the drive board 31 directly or via other components. The drive board 31 is detachably fixed to the support part 25 of the housing 21 by fixing members (not shown) such as screws.

[0041] The drive board 31 may be a component of the power factor correction circuit module 3, or may be a component of the power conversion device 2 outside the power factor correction circuit module 3.

[0042] The housing 21 is a flat plate-like member extending along the XY plane. The housing 21 is formed by die-casting, for example, but may be formed of iron or a material other than an alloy. The housing 21 may be formed of a material other than metal as long as it can transport heat from components such as the power factor correction circuit module 3 arranged on the housing 21 to the coolant flowing through the flow path 23 inside the housing 21.

[0043] The housing 21 is also provided with a liquid-cooling mechanism that uses a coolant such as antifreeze as the working fluid. Specifically, as shown in Fig. 3, a coolant flow path 23 is formed inside the housing 21. In the housing 21 according to the embodiment, the flow path 23 extends in a direction along the XY plane (for example, the horizontal direction). In other words, the flow path 23 running within one plane is formed inside the housing 21.

[0044] The flow paths 23 may branch in at least two directions along the XY plane. On the other hand, the flow paths 23 according to the embodiment do not branch in the direction along the Z direction. In other words, if the housing 21 according to the embodiment has an intersection where at least two flow paths 23 intersect, each flow path 23 extends from the intersection in a direction along the XY plane, but does not extend in a direction along the Z direction. In this way, the power conversion device 2 according to the present disclosure can configure a cooling mechanism for the entire system using flow paths 23 that run only within one plane (the XY plane).

[0045] The power factor correction circuit module 3 and the housing 21 are thermally connected. Here, being thermally connected means being configured to allow heat exchange. Heat transfer between the power factor correction circuit module 3 and the housing 21 is achieved by, for example, thermal conduction, but other forms may be used in addition to or instead of thermal conduction. Heat transfer between the power factor correction circuit module 3 and the housing 21 may also be achieved via other components.

[0046] 2, other components of the power conversion device 2, such as a transformer 73, are also disposed on the housing 21. The transformer 73 is covered by a casing 75. The casing 75 is formed of, for example, metal, and shields electromagnetic noise from the transformer 73. The transformer 73 and the drive board 31 are electrically connected by, for example, a fixing member 77 such as a screw, soldering, or the like.

[0047] Generally, in a power conversion device, the transformer 73 is a larger component (large part) than the other components. For this reason, the height (length in the Z direction) of the support portion 25 of the housing 21 that supports the drive substrate 31 is determined so that the transformer 73 fits between the housing 21 and the drive substrate 31. In other words, the height (size in the Z direction) of the power conversion device 2 depends on the distance between the housing 21 and the drive substrate 31 via the transformer 73. In other words, if the distance (size in the Z direction) between the housing 21 and the drive substrate 31 is determined based on the size of a large part such as the transformer 73, there will be excess height at the location where other components are arranged, i.e., at a position different from the large part in the X and Y directions.

[0048] In this regard, the power conversion device 2 according to the present disclosure has a power factor correction circuit module 3 in which some of the components other than the transformer 73 are modularized. The power factor correction circuit module 3 is inserted between the housing 21 and the drive board 31, the spacing of which is determined in accordance with the transformer 73. In other words, the power factor correction circuit module 3 according to the present disclosure is configured to be smaller in the height direction (Z direction) than the other large components of the power conversion device 2, thereby realizing a miniaturization of the power conversion device 2.

[0049] As shown in FIGS. 2 and 3, the power factor correction circuit module 3 further includes relay substrates 32a and 32b, an insulating heat sink 33, and a resin mold .

[0050] 3, the drive substrate 31 is detachably fixed to the resin mold 35 by fixing members 39a such as screws.

[0051] Each of the relay substrates 32a and 32b is electrically connected to the drive substrate 31. A wiring pattern is provided on the relay substrate 32. The relay substrate 32 electrically connects electrically connected components to the drive substrate 31 via the wiring pattern. For example, some components of the power factor correction circuit module 3 (power conversion device 2) are electrically connected to the drive substrate 31 via the relay substrate 32. As shown in FIG. 3, the relay substrate 32a is detachably fixed to the resin mold 35 by fixing members 39b such as screws. Furthermore, the relay substrate 32b is detachably fixed to the resin mold 35 by fixing members 39c such as screws. In other words, the resin mold 35 supports each of the relay substrates 32a and 32b.

[0052] The electrical connection between the drive substrate 31 and the relay substrate 32 may be realized by soldering, or may be realized by a detachable connection via a connector.

[0053] 2 and 3, the insulating heat sink 33 is disposed below (on the Z-side) the resin mold 35. The resin mold 35 is fixed to the surface (first main surface) of the insulating heat sink 33 facing the drive substrate 31 with fixing members (not shown) such as screws or adhesive. In other words, the resin mold 35 supports the insulating heat sink 33.

[0054] The insulating heat sink 33 is a member formed in the shape of a flat plate extending along the XY plane. The insulating heat sink 33 has thermal conductivity (preferably high thermal conductivity) and electrical insulation. Specifically, the insulating heat sink 33 may be made of any material capable of transporting heat in the thickness direction (Z direction), such as a metal plate, but may also be made of a non-metal material. Here, the insulating heat sink 33 according to this embodiment is an example of a cooling plate.

[0055] An insulating layer having electrical insulation properties is formed on the outer surface of insulating heat sink 33. That is, an insulating layer is provided between each of MOSFETs 51, 61 and insulating heat sink 33. The insulating layer on the outer surface of insulating heat sink 33 may be formed by applying a coating of an electrically insulating material, or by providing an electrically insulating sheet-like member on the outer surface. In addition, insulating heat sink 33 may be a plate-like member made of a thermally conductive and electrically insulating material.

[0056] At least the housing 21 side (Z- side) of the insulating heat sink 33 is formed in a shape that follows the shape of the arrangement position of the power factor correction circuit module 3 above (Z+ side) the housing 21. Here, the surface of the insulating heat sink 33 on the housing 21 side (Z- side) is the cooling surface of the power factor correction circuit module 3. In other words, in the power conversion device 2, the cooling surface of the power factor correction circuit module 3 extends along the surface (XY plane) of the housing 21 on which the flow path 23 is provided. In other words, the power factor correction circuit module 3 is configured so that its cooling surface is thermally connected to the housing 21, thereby enabling heat generated inside to be dissipated to the housing 21.

[0057] As an example, the power factor correction circuit module 3 is fixed to the housing 21 by fixing the insulating heat sink 33 to the housing 21 with a fixing member 39e. That is, when the power factor correction circuit module 3 is fixed to the housing 21, the surface of the insulating heat sink 33 facing the housing 21 (second main surface) is thermally connected to the housing 21. Here, the surface of the insulating heat sink 33 facing the housing 21 is the backside of the surface of the insulating heat sink 33 facing the resin mold 35 (first main surface).

[0058] 3, the MOSFETs 51, 61 (power semiconductors) of the power factor correction circuit 5 and the DC-DC conversion circuit 6 are arranged on the surface (first main surface) of the insulating heat sink 33 facing the resin mold 35. Each of the multiple MOSFETs 51, 61 is fixed to the insulating heat sink 33 by a fixing member (not shown) such as an adhesive or an adhesive sheet. This fixing member may be made of a material that is at least thermally conductive. Note that the fixing member may be electrically insulating, in which case the insulating heat sink 33 does not need to be electrically insulating.

[0059] The cooling surface of each of the multiple MOSFETs 51, 61 faces the surface of the insulating heat sink 33 facing the resin mold 35 and is thermally connected to the insulating heat sink 33. That is, the heat dissipation path of each of the multiple MOSFETs 51, 61 is a path in the Z direction that runs from the cooling surface to the flow path 23 via the insulating heat sink 33 and the housing 21. In this way, each of the MOSFETs 51, 61 is fixed to the surface of the insulating heat sink 33 facing the resin mold 35 so that heat can be exchanged between the heat dissipation surface and the insulating heat sink 33.

[0060] 3, each of the multiple MOSFETs 51, 61 is placed flat on insulating heat sink 33. Here, "placed flat" means that each of the multiple MOSFETs 51, 61 is arranged on insulating heat sink 33 with its heat dissipation surface facing the surface of insulating heat sink 33 on the resin mold 35 side.

[0061] Each of the multiple MOSFETs 51, 61 is disposed in a gap 37 formed between the insulating heat sink 33 and the resin mold 35. In other words, each of the multiple MOSFETs 51, 61 is disposed below (on the Z- side) the electrolytic capacitor 53 via the resin mold 35. For example, each of the multiple MOSFETs 51, 61 is disposed directly below the electrolytic capacitor 53. In other words, the upper side (on the Z+ side) of each of the multiple MOSFETs 51, 61 is covered by the resin mold 35. The position (for example, the position in the X and Y directions) of each of the multiple MOSFETs 51, 61 on the insulating heat sink 33 is defined (positioned) by the resin mold 35.

[0062] Further, the leads 511, 611 of the multiple MOSFETs 51, 61 are electrically connected to the drive substrate 31. In the configurations illustrated in Figures 2 and 3, the leads 511, 611 of the multiple MOSFETs 51, 61 are electrically connected to either the relay substrate 32a, 32b by, for example, soldering.

[0063] In this way, by providing the relay board 32 in the power factor correction circuit module 3, some components of the power conversion device 2, such as the MOSFETs 51 and 61 (power semiconductors), can be electrically connected to the drive board 31 via the relay board 32, thereby improving the flexibility of their placement. For example, if the MOSFETs 51 and 61 are directly connected to the drive board 31, there are restrictions on the installation positions of the MOSFETs 51 and 61 due to factors such as the routing of wiring for the connection. On the other hand, in the power factor correction circuit module 3 according to the present disclosure, the MOSFETs 51 and 61 are indirectly connected to the drive board 31 via the relay board 32, improving the flexibility of their placement.

[0064] Note that some or all of the leads 511, 611 of the multiple MOSFETs 51, 61 may extend in the Z direction to the drive substrate 31. That is, each of the multiple MOSFETs 51, 61 may be electrically connected to the drive substrate 31 without the relay substrate 32. In this case, some or all of the relay substrate 32 may not be provided.

[0065] Note that either one of the relay substrates 32a and 32b may not be provided depending on the number and arrangement of the multiple MOSFETs 51 and 61. That is, the number of relay substrates 32 may be one. On the other hand, the number of relay substrates 32 may be three or more.

[0066] As an example, the relay substrate 32 may be provided on at least one side in the Y direction of the resin mold 35. As an example, the relay substrate 32 may be provided on at least one side in the X direction of the resin mold 35. In other words, the relay substrate 32 may be provided on at least one side portion that extends from the bottom surface portion (part of the Z-side) of the resin mold 35 toward the drive substrate 31 side and covers the electrolytic capacitor 53.

[0067] As one example, the relay substrate 32 may be provided on a bottom portion (part of the Z-side) of the resin mold 35 interposed between at least the MOSFETs 51, 61 and the electrolytic capacitor 53. For example, the relay substrate 32 may be provided on the side opposite the insulating heat sink 33 of each of the multiple MOSFETs 51, 61. For example, the relay substrate 32 may be provided between each of the multiple MOSFETs 51, 61 and the resin mold 35. For example, the relay substrate 32 may be provided inside the resin mold 35, below the electrolytic capacitor 53 (on the Z-side). In this case, the relay substrate 32 may be housed inside the resin mold 35, or may protrude from the resin mold 35.

[0068] In this way, the configuration in which the relay substrate 32 is provided on the side opposite the insulating heat sink 33 of each of the multiple MOSFETs 51, 61 further improves the degree of freedom in arranging the multiple MOSFETs 51, 61. Furthermore, this configuration allows the relay substrate 32 to reduce radiant heat (radiation heat) from the multiple MOSFETs 51, 61 to other components such as the electrolytic capacitor 53.

[0069] Furthermore, relay board 32 is not limited to a flat board, and may be a board with an L-shaped cross section. That is, relay board 32 may be formed in a shape similar to an L-shaped angle (L-shaped angle iron). That is, relay board 32 may be a board with at least one L-shaped cross section that is supported by at least two of the bottom surface portion and at least one side surface portion of resin mold 35. This L-shaped relay board 32 may be provided across two side surfaces (X direction and Y direction) of resin mold 35, or may be provided across the side surface (X direction or Y direction) and bottom surface (Z-side) of resin mold 35.

[0070] 2 and 3, the electrolytic capacitor 53 of the power factor correction circuit 5 is disposed on the side of the resin mold 35 opposite to the MOSFETs 51 and 61 (Z+ side), that is, inside the resin mold 35. In other words, the electrolytic capacitor 53 is disposed on the drive substrate 31 side, which is the side opposite to the insulating heat sink 33 with respect to the MOSFETs 51 and 61.

[0071] The leads 531 of the electrolytic capacitor 53 are electrically connected to the drive substrate 31. For example, the electrolytic capacitor 53 is fixed to the drive substrate 31 by soldering or the like and is supported by the drive substrate 31. As an example, the electrolytic capacitor 53 is arranged suspended from the drive substrate 31 toward the resin mold 35. The electrolytic capacitor 53 may also be held by the resin mold 35, or its position relative to the drive substrate 31 may be specified (positioned). The electrolytic capacitor 53 may also be supported by the resin mold 35.

[0072] In this way, the resin mold 35 is interposed at least between the MOSFETs 51, 61 and the electrolytic capacitor 53, and can reduce radiant heat from the multiple MOSFETs 51, 61 to the electrolytic capacitor 53. More specifically, in the power factor correction circuit module 3 according to the present disclosure, the MOSFETs 51, 61 and the electrolytic capacitor 53 are covered with the resin mold 35. That is, in the power factor correction circuit module 3 according to the present disclosure, the resin mold 35 serves to hold and position the MOSFETs 51, 61 and to insulate the electrolytic capacitor 53.

[0073] Resin mold 35 may further position not only MOSFETs 51 and 61 but also other components such as electrolytic capacitor 53. In other words, resin mold 35 defines (positions) at least the positions of MOSFETs 51 and 61.

[0074] The gap 37 between the insulating heat sink 33 and the resin mold 35, or the gap between the resin mold 35 and the electrolytic capacitor 53, may be filled with a heat dissipation buffer material such as a gap filler that has at least heat dissipation properties (thermal conductivity). In other words, the heat dissipation buffer material such as the gap filler may be used as a thermal capacity. This can further improve the heat dissipation performance from the power factor correction circuit module 3. Preferably, the gap filler also has electrical insulation properties.

[0075] A reflective or absorptive heat-shielding layer that prevents heat transfer to the electrolytic capacitor 53 via the resin mold 35 may be formed on the side of the resin mold 35 facing each of the multiple MOSFETs 51, 61. A reflective heat-shielding layer, for example, that prevents heat transfer from the outside may be formed on the outer surface of the electrolytic capacitor 53. These heat-shielding layers may be formed, for example, by applying a heat-shielding coating to the outer surface of the resin mold 35. This can further improve the heat dissipation performance from the power factor correction circuit module 3 and suppress thermal degradation of the electrolytic capacitor 53.

[0076] The power conversion device 2 according to the present disclosure can be expanded by mounting a plurality of power factor correction circuit modules 3 in parallel. That is, the power conversion device 2 according to the present disclosure has expandability by modularizing the MOSFETs 61 of the power factor correction circuit 5 and the DC-DC conversion circuit 6. For example, the power conversion device 2 can increase its output (kW) by electrically connecting a number of power factor correction circuit modules 3 in parallel that corresponds to the amount of power converted, i.e., the magnitude of the DC voltage output (kW), i.e., by increasing the number of modules.

[0077] As described above, in the power conversion device 2 according to the present disclosure, the power factor correction circuit structure required for power conversion is modularized. Specifically, in the power factor correction circuit module 3 according to the present disclosure, each of the multiple MOSFETs 51, 61 is placed flat on the insulating heat sink 33. Therefore, in the housing 21 of the power conversion device 2, the internal flow path 23 is formed as a flow path that runs only in the horizontal direction (XY direction), thereby preventing the accumulation of the working fluid (coolant). Furthermore, in the power factor correction circuit module 3 according to the present disclosure, the use of the relay substrate 32 improves the flexibility in the arrangement of the MOSFETs 51, 61. Furthermore, by fitting the power factor correction circuit module 3 according to the present disclosure more compactly in the height direction than large components such as the transformer 73, the overall size of the power conversion device 2 can be reduced.

[0078] According to at least one of the embodiments described above, it is possible to reduce the size of the power conversion device by taking heat dissipation into consideration.

[0079] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention described in the claims and their equivalents.

[0080] (Addendum) The above description of the embodiments discloses the following techniques. (1) a housing having a flow path formed therein that runs within one plane; a power factor correction circuit module detachably fixed to the housing, The power factor correction circuit module includes: a cooling plate having thermal conductivity and formed in a flat plate shape; a power semiconductor whose heat dissipation surface faces a first main surface of the cooling plate, is fixed to the first main surface so as to be able to exchange heat with the cooling plate, and is electrically connected to a drive board; an electrolytic capacitor disposed on the drive substrate opposite the cooling plate with respect to the power semiconductor and electrically connected to the drive substrate; a resin mold fixed to the first main surface of the cooling plate, defining the position of the power semiconductor, and interposed at least between the power semiconductor and the electrolytic capacitor; When the power factor correction circuit module is fixed to the housing, a second main surface of the cooling plate, which is a surface opposite to the first main surface, is thermally connected to the housing. Power conversion device. (2) The leads of the power semiconductor extend to the drive substrate. The power conversion device according to (1) above. (3) the power factor correction circuit module further includes a relay board electrically connected to the drive board; the resin mold supports the relay substrate; The power semiconductor is electrically connected to the relay substrate and is connected to the drive substrate via the relay substrate. The power conversion device according to (1) above. (4) the resin mold has a bottom surface portion interposed between the power semiconductor and the electrolytic capacitor, and at least one side surface portion extending from the bottom surface portion toward the drive substrate and covering the electrolytic capacitor, the relay substrate is at least one substrate supported by at least one of the bottom surface portion and the at least one side surface portion of the resin mold; The power conversion device according to (3) above. (5) the relay substrate is a substrate having at least one L-shaped cross section and supported by at least two of the bottom surface portion and the at least one side surface portion of the resin mold; The power conversion device according to (4) above. (6) The relay substrate is at least one substrate supported by a bottom surface of the resin mold interposed between the power semiconductor and the electrolytic capacitor. The power conversion device according to (3) above. (7) the power semiconductor is disposed in a gap between the first main surface of the cooling plate and the resin mold; The gap is filled with a heat dissipation buffer material. The power conversion device according to any one of (1) to (6) above. (8) The power factor correction circuit module further includes the drive substrate. The power conversion device according to any one of (1) to (7) above. (9) The number of power factor correction circuit modules is determined according to the amount of power to be converted. The power conversion device according to any one of (1) to (8) above. (10) a transformer fixed to the housing and electrically connected to the drive board; the power factor correction circuit module is smaller than the transformer in a direction from the housing toward the drive board; The power conversion device according to any one of (1) to (9) above. (11) The power conversion device according to any one of (1) to (10) above, which converts AC power from an external AC power source into DC power; a battery that is charged using the DC power converted by the power conversion device. vehicle. [Explanation of symbols]

[0081] 1 Charging System 11 AC power supply 13 Load 2. Power conversion device 21. Cabinet 23 Flow path 25 Support part 3 Power Factor Correction Circuit Module 31 Drive board 32 Relay board 33 Insulating heat sink 35 Resin mold 37 Gap 39 Fixing member 4 Noise Filter 5 Power factor correction (PFC) circuit 51 MOSFET (power semiconductor) 511 leads 53 Electrolytic capacitor 531 leads 6 DC-DC conversion circuit 61 MOSFET (power semiconductor) 611 leads 63 Coil 73 Trans 75 Casing 77 Fixing member 81 MOSFET (power semiconductor) 83 Coil 85 output capacitor

Claims

1. a housing having a flow path formed therein that runs within one plane; a power factor correction circuit module detachably fixed to the housing, The power factor correction circuit module includes: a cooling plate having thermal conductivity and formed in a flat plate shape; a power semiconductor having a heat dissipation surface facing a first main surface of the cooling plate, fixed to the first main surface so as to be able to exchange heat with the cooling plate, and electrically connected to a drive substrate; an electrolytic capacitor disposed on the drive substrate opposite the cooling plate with respect to the power semiconductor and electrically connected to the drive substrate; a resin mold fixed to the first main surface of the cooling plate, defining the position of the power semiconductor, and interposed at least between the power semiconductor and the electrolytic capacitor; a second main surface of the cooling plate, which is a surface opposite to the first main surface, being thermally connected to the housing when the power factor correction circuit module is fixed to the housing; Power conversion device.

2. The leads of the power semiconductor extend to the drive substrate. The power conversion device according to claim 1 .

3. the power factor correction circuit module further includes a relay board electrically connected to the drive board; the resin mold supports the relay substrate; The power semiconductor is electrically connected to the relay substrate and is connected to the drive substrate via the relay substrate. The power conversion device according to claim 1 .

4. the resin mold has a bottom surface portion interposed between the power semiconductor and the electrolytic capacitor, and at least one side surface portion extending from the bottom surface portion toward the drive substrate and covering the electrolytic capacitor, the relay substrate is at least one substrate supported by at least one of the bottom surface portion and the at least one side surface portion of the resin mold; The power conversion device according to claim 3 .

5. the relay substrate is a substrate having at least one L-shaped cross section and supported by at least two of the bottom surface portion and the at least one side surface portion of the resin mold; The power conversion device according to claim 4.

6. The relay substrate is at least one substrate supported by a bottom surface of the resin mold interposed between the power semiconductor and the electrolytic capacitor. The power conversion device according to claim 3 .

7. the power semiconductor is disposed in a gap between the first main surface of the cooling plate and the resin mold; The gap is filled with a heat dissipation buffer material. The power conversion device according to claim 1 .

8. The power factor correction circuit module further includes the drive substrate. The power conversion device according to claim 1 .

9. The number of power factor correction circuit modules is determined according to the amount of power to be converted. The power conversion device according to any one of claims 1 to 8.

10. a transformer fixed to the housing and electrically connected to the drive board; the power factor correction circuit module is smaller than the transformer in a direction from the housing toward the drive board; The power conversion device according to any one of claims 1 to 8.

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