JP5741205B2 - Power control unit - Google Patents

Description

  The present invention relates to the structure of a power control unit.

  For example, a power control unit used in a hybrid (HV) vehicle includes an electronic control unit (ECU), an inverter, a capacitor, and a voltage converter (DC / DC converter). Each of these devices is housed in a case, and these cases are stacked to constitute one case as a power control unit.

  Since the inverter housing including the inverter has a large amount of heat generated by the inverter, a cooling mechanism for cooling the inverter is provided. In addition, since the voltage converter has a circuit board on which many electronic components are mounted, and the heat generated from the electronic components is large, it is necessary to cool the voltage converter efficiently.

  Patent Document 1 (JP 2010-022161 A), Patent Document 2 (JP 2009-291044 A), Patent Document 3 (JP 2007-329230 JP), and Patent Document 4 (JP 2005-278277 A). (Patent Publication) discloses a cooling structure related to an electric junction box, an electronic circuit device, and an electric motor.

JP 2010-022161 A JP 2009-291044 A JP 2007-329230 A JP 2005-278277 A

  In recent years, in a power control unit, it has become necessary to suppress the temperature rise inside the casing that houses the voltage converter due to heat generated from the windings of the transformer and the choke coil that are components of the voltage converter. Yes.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a power control unit having a structure for suppressing a temperature rise inside a voltage converter.

  A power control unit based on the present invention is a power control unit comprising a voltage converter housing including a voltage converter therein, and an inverter housing including an inverter inside and a cooling mechanism for the inverter. A voltage converter terminal region provided on the outer surface of the voltage converter housing, to which the voltage converter is electrically connected, a relay terminal region provided on the outer surface of the inverter housing, and the voltage conversion A bus bar for electrically connecting the terminal area and the relay terminal area.

In another embodiment, a rod is used as the wire for the bus bar, and terminal portions are formed by crushing the wire in a plate shape at both ends of the bus bar.

In another embodiment, the relay terminal region electrically insulates between a relay plate that electrically connects one end of the bus bar and one end of the external cable, and the relay plate and the outer surface of the inverter housing. Insulating structure.

  In another form, the apparatus further includes a capacitor case including a capacitor, and the capacitor case is provided between the voltage converter case and the inverter case.

  In another form, when the power control unit is mounted on a vehicle, the relay terminal region is provided on the outer surface of the inverter casing facing the front side of the vehicle.

  According to the power control unit based on the present invention, it is possible to suppress the temperature rise inside the voltage converter.

It is the schematic which shows the planar structure of a vehicle. It is a perspective view of the power control unit in the arrow A arrow direction in FIG. It is a figure which shows the edge part structure of the bus bar used for the power control unit of this Embodiment. It is sectional drawing which shows the internal structure of the voltage converter terminal area | region of the power control unit of this Embodiment. It is sectional drawing which shows the internal structure of the relay terminal area | region of the power control unit of this Embodiment. It is sectional drawing which shows the other internal structure of the relay terminal area | region of the power control unit of this Embodiment.

  The structure of the power control unit in the embodiment based on the present invention will be described below with reference to the drawings. In each embodiment described below, when referring to the number, amount, and the like, the scope of the present invention is not necessarily limited to the number, amount, and the like unless otherwise specified. The same parts and corresponding parts are denoted by the same reference numerals, and redundant description may not be repeated. In addition, it is planned from the beginning to use the structures in the embodiments in appropriate combinations.

  First, a schematic structure around a power control unit used in a hybrid (HV) vehicle will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic view showing a planar structure of the vehicle, and FIG. 2 is a perspective view of the power control unit 100 as viewed in the direction of arrow A in FIG.

  Referring to FIG. 1, in a hybrid (HV) vehicle 1, an engine 10 and a transaxle 20 are arranged on the front side of the vehicle 1. Transaxle 20 includes a motor generator (MG1, MG2) and the like. The motor generator (MG1.MG2) and the like are connected to the power control unit 100. Power is supplied to the power control unit 100 from the HV battery 50 disposed on the rear side of the vehicle 1 through the power cable 40.

  Referring to FIG. 2, power control unit 100 includes an electronic control unit (ECU) 110, an inverter 120, a capacitor 130, and a voltage converter (hereinafter referred to as a DC / DC converter) 140. Each of these devices is housed in the ECU housing 110A, the inverter housing 120A, the capacitor housing 130A, and the DC / DC converter housing 140A, and the respective housings are stacked. The power control unit 100 constitutes one housing.

  A cooling mechanism (not shown) for cooling the inverter 120 is provided in the inverter housing 120A because the amount of heat generated by the inverter 120 is large.

  In the present embodiment, on the outer surface of DC / DC converter housing 140A, a voltage converter terminal at which DC / DC converter 140 is electrically connected to an external electronic device on the side surface side when viewed from the traveling direction of vehicle 1. A region 200 is provided.

  In the present embodiment, on the outer surface of inverter casing 120A, relay terminal region 400 is provided on the front side as viewed from the traveling direction of vehicle 1.

  The voltage converter terminal area 200 and the relay terminal area 400 are electrically connected by the bus bar 300 so as to wrap around along the outer surface of the power control unit 100. In addition, one end of an external cable 500 that is electrically connected to an external electronic device (for example, a relay box) is connected to the relay terminal region 400.

(Structure of bus bar 300)
Next, the structure of the bus bar 300 will be described with reference to FIG. FIG. 3 is a view showing an end structure of the bus bar 300 used in the power control unit 100. A solid round bar 301 is used for the wire rod of the bus bar 300 in the present embodiment. For the round bar 301, for example, a copper round bar having a diameter of about 6 mm is used. The surface of the round bar 301 is covered with a resin insulating film 302. In addition, it is not restricted to a round bar, A cross section may be a rectangle if it is a bar.

  Terminal portions 301 a are formed at both ends of the bus bar 300. Since the shape of the terminal portion 301a provided at both ends is the same, only the structure of the terminal portion 301a on one end side is shown in FIG.

  The terminal portion 301a has a rectangular shape obtained by crushing the wire rod of the round bar 301 into a plate shape. A bolt hole 301h that can be used for fixing to the terminal block side is opened at a substantially central portion of the terminal portion 301a.

(Voltage converter terminal area 200)
Next, the structure of the voltage converter terminal region 200 will be described with reference to FIG. FIG. 4 is a cross-sectional view showing the internal structure of the voltage converter terminal region 200 used in the power control unit 100. An aluminum terminal block 142 is fixed to a circuit board 141 on which a transformer, a choke coil, and the like, which are components of the DC / DC converter 140, are mounted using bolts 143.

  Here, aluminum is used as the material of the DC / DC converter casing 140A for the purpose of enhancing the heat dissipation performance and applying the ground potential. For this reason, the terminal block 142 and the DC / DC converter housing 140 </ b> A are insulated by using the resin spacer 204. For the spacer 204, it is preferable to use a resin material excellent in heat conduction and electrical insulation. For example, a PBT (PBT: polybutylene terephthalate) resin may be used.

  The terminal block 142 is connected so as to be electrically connected to the terminal portion 301 a on one end side of the bus bar 300 using a bolt 202 and a washer 203. Further, the voltage converter terminal region 200 has a resin cover 201 so as to cover the terminal block 142 exposed from the spacer 204, the terminal portion 301 a and the bolt 202.

(Relay terminal area 400)
Next, the structure of the relay terminal region 400 will be described with reference to FIG. FIG. 5 is a cross-sectional view showing the internal structure of the relay terminal region 400 used in the power control unit 100. Although not shown, a water-cooling cooling mechanism is built in the inverter casing 120A in the present embodiment.

  In the relay terminal region 400, the relay terminal case 401 is fixed to the inverter housing 120A using bolts 410 and washers 411. An insulating spacer 412 is provided between the bolt 410 and the relay terminal case 401.

  The relay terminal case 401 is a second terminal that electrically connects the first terminal bolt 402 that electrically connects the terminal portion 301 a on the other end side of the bus bar 300 and the terminal portion 501 a that is provided on one end side of the external cable 500. A terminal bolt 405 is accommodated. A terminal portion 301 a and a connecting bar 404 are fastened to the first terminal bolt 402 using a nut 403. The terminal portion 501 a and the connecting bar 404 are fastened to the second terminal bolt 405 using a nut 406. As a result, the bus bar 300 and the external cable 500 are electrically connected.

  Further, the relay terminal case 401 includes a resin cover 410 so as to cover the first terminal bolt 402, the second terminal bolt 405, the terminal portions 301a and 501a, the connecting bar 404, and the nuts 403 and 405.

  An insulating member 600 is provided between the surface of the relay terminal case 401 facing the inverter casing 120A and the surface of the inverter casing 120A. As with the DC / DC converter housing 140A, an aluminum material is used for the inverter housing 120A for the purpose of improving the heat dissipation performance and applying a ground potential.

  For this reason, it is for improving the insulation performance between the 1st terminal volt | bolt 402 and the 2nd terminal volt | bolt 405 to which the voltage of 12V is applied, and the inverter housing | casing 120A more. For the relay terminal case 401, the insulating spacer 412, and the insulating member 600, it is preferable to use a resin material excellent in heat conduction and electrical insulation. For example, a PBT (PBT: polybutylene terephthalate) resin may be used.

  In addition, instead of the insulating member 600, the surface of the relay terminal case 401 facing the inverter housing 120A is made thicker than the other regions, so that the surface of the relay terminal case 401 facing the inverter housing 120A is thickened. It is also possible to improve the insulation performance and heat conduction performance.

  In addition, when the insulation performance and the heat conduction performance are sufficient only with the relay terminal case 401, the insulation member 600 is not provided, as shown in the cross-sectional view of the other internal structure in FIG. It is also possible to employ a configuration in which a gap is provided between the surface facing the inverter casing 120A and the inverter casing 120A.

  As described above, according to the power control unit 100 in the present embodiment, the voltage converter terminal region where the DC / DC converter 140 is electrically connected to the external electronic device is provided on the outer surface of the DC / DC converter housing 140A. 200 is provided, and a relay terminal region 400 is provided on the outer surface of the inverter casing 120A. The voltage converter terminal region 200 and the relay terminal region 400 are electrically connected by the bus bar 300.

  Thereby, the heat generated by the DC / DC converter 140 is radiated to the bus bar 300 through the voltage converter terminal region 200. Bus bar 300 is connected to relay terminal region 400 provided on the outer surface of inverter casing 120A. Since the inverter housing 120 </ b> A is cooled by the cooling mechanism provided therein, the heat of the DC / DC converter 140 transferred to the bus bar 300 is also cooled in the relay terminal region 400.

  Thus, the heat generated by the DC / DC converter 140 using the bus bar 300 can be efficiently cooled using the inverter housing 120A. Moreover, heat conduction is promoted by using a copper round bar for the round bar 301 of the bus bar 300. Furthermore, since the terminal portion 301a has an integrated structure in which the wire rod of the round bar 301 is crushed into a plate shape, it is possible to reduce the heat conduction loss between the terminal portion 301a and the round bar 301.

  In power control unit 100 in the present embodiment, voltage converter terminal region 200 is provided on the side surface side when viewed from the traveling direction of vehicle 1, and relay terminal region 400 is disposed on the front side when viewed from the traveling direction of vehicle 1. Provided. Thereby, the routing distance of the bus bar 300 can be shortened, and it becomes possible to promote heat conduction and minimize power loss in the wiring.

  Although the embodiments of the present invention have been described above, the embodiments disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  1 vehicle, 10 engine, 20 transaxle, 40 power cable, 50 battery, 100 power control unit, 110A housing, 120 inverter, 120A inverter housing, 130 capacitor, 130A capacitor housing, 140 DC / DC converter, 140A converter Case, 141 circuit board, 142 terminal block, 143, 202, 410 volts, 200 voltage converter terminal area, 201, 410 cover, 203, 411 washer, 204 spacer, 300 bus bar, 301 round bar, 301a, 501a terminal part , 301h Bolt hole, 302 Insulating film, 400 Relay terminal area, 401 Relay terminal case, 402 First terminal bolt, 403, 405, 406 Nut, 404 Connecting bar, 405 Second terminal DOO, 412 an insulating spacer, 500 external cables, 600 an insulating member.

Claims (4)

A power control unit comprising a voltage converter housing including a voltage converter therein, and an inverter housing including an inverter inside and a cooling mechanism for the inverter,
A voltage converter terminal region provided on the outer surface of the voltage converter housing, to which the voltage converter is electrically connected;
A relay terminal area provided on the outer surface of the inverter housing;
A bus bar for electrically connecting the voltage converter terminal area and the relay terminal area;
Equipped with a,
The relay terminal area is
A relay plate for electrically connecting one end of the bus bar and one end of the external cable;
An insulating structure that electrically insulates between the relay plate and the outer surface of the inverter housing,
Power control unit. The bus bar uses a bar as a wire,
The power control unit according to claim 1, wherein terminal portions obtained by crushing the wire rod into a plate shape are formed at both ends of the bus bar. Further equipped with a capacitor housing including a capacitor inside,
The power control unit according to claim 1 or 2 , wherein the capacitor casing is provided between the voltage converter casing and the inverter casing. When the power control unit is mounted on a vehicle,
The power control unit according to any one of claims 1 to 3 , wherein the relay terminal area is provided on the outer surface of the inverter casing facing the front side of the vehicle.

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