JP5048705B2 - Power converter for vehicle - Google Patents

Description

  The present invention relates to a vehicular power conversion device for converting power supplied from a power source and supplying the power to a drive motor.

  For example, fuel cell vehicles, hybrid vehicles incorporating an engine (internal combustion engine), electric vehicles, and the like are known as vehicles that are driven by a drive motor. In this type of automobile, a power conversion device is used. The power conversion device generally includes a battery that is a power source, a DC / DC converter that steps down or boosts DC power from the battery, and the DC. An inverter that converts direct current power from the DC converter into alternating current and a drive motor that is rotationally driven by the alternating current power from the inverter are provided.

The power conversion device is desired to be miniaturized for in-vehicle use. For example, a power conversion unit disclosed in Patent Document 1 is known. This power conversion unit receives DC power from a DC power supply, converts the input DC power into DC power having a different voltage value, and outputs DC power from the DC / DC converter. An inverter that is input and converts the input DC power into AC and outputs; a first capacitor provided on the input side of the DC / DC converter; and a second capacitor provided on the input side of the inverter; And the second capacitor is housed in a common package.

  Specifically, as shown in FIG. 8, a filter capacitor C1, a smoothing capacitor C2, a snubber capacitor C3, a DC / DC converter (reactor L, power transistors Q1, Q2), an inverter (power transistors Q11 to Q16). The inverters (power transistors Q21 to Q26) are housed in a common housing 1 and modularized. The casing 1 is formed with a refrigerant flow path 2 through which a refrigerant such as a coolant flows.

  The filter capacitor C1, the smoothing capacitor C2, and the snubber capacitor C3 are accommodated in a common capacitor package 3. In the capacitor package 3, a heat transfer suppression slit (air layer) is disposed between the filter capacitor C1 and the smoothing capacitor C2, and the filter capacitor C1 having a high heat resistance temperature is lower than the heat resistance temperature. The heat transmitted to the smoothing capacitor C2 is suppressed.

JP 2009-044920 A

  However, in Patent Document 1, although the filter capacitor C1, the smoothing capacitor C2, and the snubber capacitor C3 are covered with potting resin in the capacitor package 3, the capacitor package 3 and the reactor L are considerably different. It is arranged at a separated position.

  Although not shown, reactor L and filter capacitor C1 are electrically connected by a bus bar, and this bus bar is elongated. As a result, there is a problem that noise is easily generated and that the bus bar becomes high temperature due to a large current flowing therethrough.

  The present invention solves this type of problem, and can efficiently cool a connection path for electrically connecting a capacitor and a reactor, and can be configured compactly and easily. An object is to provide an apparatus.

  The present invention relates to a vehicular power converter for converting electric power supplied from a power source and supplying the electric power to a drive motor.

  A power converter for a vehicle includes a switching module, a capacitor that smoothes a voltage output from the switching module, a reactor that is disposed adjacent to the capacitor, and a thermally conductive insulation that embeds the capacitor and the reactor. A heat insulating member disposed between the member, the capacitor and the reactor, and blocking heat conduction from the reactor to the capacitor via the heat conductive insulating member; and the heat conductive insulation An integrated connecting portion that is provided inside the member and integrates the heat-conductive insulating member on the capacitor side and the heat-conductive insulating member on the reactor side with the heat shield member interposed therebetween; and the integrated connection And a connection path that electrically connects the capacitor and the reactor.

  Moreover, it is preferable that a heat-shielding member has an edge part inside spaced apart from the exposed surface of a heat conductive insulating member, and an integrated connection part is formed between the said exposed surface and the said edge part.

  Furthermore, it is preferable that the heat shield member has a hole portion opened inside the heat conductive insulating member, and the integrated connection portion is formed in the heat conductive insulating member filled in the hole portion. .

  Furthermore, it is preferable that the vehicular power conversion device includes a casing that houses a switching module, a capacitor, and a reactor, and a heat sink is provided at an end of the casing.

  Moreover, it is preferable that a switching module is provided at the end of the housing, and that the reactor and the capacitor are arranged in this order along the direction away from the end.

  Furthermore, the capacitor preferably includes an input side capacitor and an output side capacitor of the switching module, and the negative terminal of the input side capacitor and the output side capacitor is preferably shared within the heat conductive insulating member.

  Furthermore, it is preferable that the vehicular power converter is provided with a reactor and a capacitor on a lower voltage side than the switching module.

  According to the present invention, a heat shield member that blocks heat conduction from the reactor to the capacitor is disposed between the capacitor and the reactor. For this reason, even if it arrange | positions a capacitor | condenser and a reactor adjacent, the said capacitor | condenser is not influenced by a heat | fever. Therefore, the vehicle power conversion device can be made compact, and the connection path for electrically connecting the capacitor and the reactor is made as short as possible. As a result, noise and high temperature are suppressed in the connection path, and the capacitor is not affected.

  Further, the connection path is disposed in an integrated connecting portion provided inside the heat conductive insulating member. For this reason, it is possible to satisfactorily cool the connection path with a simple configuration and reliably prevent the capacitor from being affected by heat.

1 is a schematic configuration diagram of an in-vehicle drive system to which a vehicle power conversion device according to a first embodiment of the present invention is applied. It is a schematic plane explanatory view of the power converter. It is a schematic front explanatory drawing of the said power converter device. It is a section explanatory view of LC unit which constitutes the power converter. It is a section explanatory view of LC unit which constitutes the power converter for vehicles concerning a 2nd embodiment of the present invention. It is a section explanatory view of LC unit which constitutes the power converter for vehicles concerning a 3rd embodiment of the present invention. It is a schematic plan explanatory drawing of the vehicle power converter device which concerns on the 4th Embodiment of this invention. It is explanatory drawing of the power conversion unit currently disclosed by patent document 1. FIG.

  As shown in FIG. 1, an in-vehicle drive system 12 to which the vehicle power conversion device 10 according to the first embodiment of the present invention is applied includes a fuel cell (power source) 14 and a power storage device ( (Hereinafter referred to as a battery) 16, and a DC / DC converter 20 capable of connecting the fuel cell 14 and the battery 16 on a power feeding circuit 18.

  The fuel cell 14 and the DC / DC converter 20 can be connected to an inverter 24 via bus lines 22 a and 22 b constituting the power supply circuit 18, and a current (electric power) is supplied to a driving motor 26 for vehicle travel through the inverter 24. Is supplied.

  Although not shown, the fuel cell 14 includes a power generation cell in which an electrolyte membrane / electrode structure in which both sides of a solid polymer electrolyte membrane are sandwiched between an anode side electrode and a cathode side electrode is sandwiched between separators, and a plurality of power generation cells are provided. They are stacked.

  The DC / DC converter 20 includes a smoothing primary capacitor (input capacitor) 30 and a secondary capacitor (output capacitor) 32, respectively. The secondary side capacitor 32 is connected to the bus lines 22a and 22b via the power lines 33a and 33b.

  The DC / DC converter 20 is configured as an arm composed of an upper arm element 34 and a lower arm element 36 that are switching elements such as IGBTs. The arm elements 34 and 36 are connected to diodes 38 and 40 (anti-parallel diodes) in parallel in opposite directions to constitute a switching module 41.

  When the DC / DC converter 20 converts the voltage between the primary side voltage and the secondary side voltage, one reactor 42 that releases and stores energy (transforms the current) includes the midpoint of the arm and the battery. 16 is inserted. Reactor 42 and primary side capacitor 30 are connected via a bus bar (connection path) 44.

  The upper arm element 34 is turned on by the high level of the gate drive signal (drive voltage) VH, and the lower arm element 36 is turned on by the high level of the gate drive signal (drive voltage) VL.

  The battery 16 is connected to the primary side of the DC / DC converter 20 via power lines 46a and 46b. As the battery 16, for example, a lithium ion secondary battery or a capacitor can be used.

  The inverter 24 performs DC / AC conversion and supplies the motor current to the driving motor 26, while the motor current after AC / DC conversion accompanying the regenerative operation is changed from the secondary side to the primary side through the DC / DC converter 20. Supply. The secondary side voltage, which is the regenerative voltage or the generated voltage, is converted into a low primary side voltage by the DC / DC converter 20.

  As shown in FIGS. 2 and 3, the power conversion device 10 includes a housing 50, and the switching module 41 and the LC unit 52 are accommodated in the housing 50. A heat sink 54 is provided at an end (for example, bottom) 50a of the casing 50, and a switching module 41 is disposed in the casing 50 on the inner surface side of the end 50a. A coolant such as cooling water is supplied into the heat sink 54.

  The LC unit 52 includes a primary side capacitor 30, a secondary side capacitor 32, and a reactor 42 that are integrally embedded in a frame member 56 via a heat conductive insulating member 58. The heat conductive insulating member 58 is made of a resin excellent in heat dissipation and heat resistance, for example, an epoxy resin.

  In the frame member 56, as shown in FIGS. 3 and 4, the reactor 42, the primary capacitor 30, and the secondary capacitor 32 are arranged in this order from the one end 56 a side of the frame member 56. A heat shield member 60 is provided on the bottom portion 56 b of the frame member 56, located between the reactor 42 and the primary side capacitor 30, for blocking heat conduction from the reactor 42 to the primary side capacitor 30.

  The heat shield member 60 has, for example, a plate shape made of urethane or the like, and has an end portion 60 a that is separated from the exposed surface 58 a of the heat conductive insulating member 58 by a distance S. Between the exposed surface 58a and the end portion 60a, an integrated connecting portion 62 for arranging the bus bar 44 inside the heat conductive insulating member 58 is formed.

  As shown in FIG. 4, the integrated connecting portion 62 is provided inside the heat conductive insulating member 58, and the heat conductive insulating member 58 on the primary capacitor 30 side and the reactor 42 side across the heat shield member 60. The heat conductive insulating member 58 is integrated. The integrated connecting portion 62 is provided with a bus bar 44 that electrically connects the primary side capacitor 30 and the 42 reactor 42.

  Reactor 42 exposes L terminal 42a connected to power line 46a and L terminal 42b connected to the midpoint of switching module 41 from thermally conductive insulating member 58 to the outside.

  The primary capacitor 30 has a plus terminal 30 a and a minus terminal 30 b, and the plus terminal 30 a is connected to the L terminal 42 a of the reactor 42 through the bus bar 44. The minus terminal 30 b is shared by joining the minus terminal 32 b of the secondary side capacitor 32 inside the heat conductive insulating member 58. The common minus terminal 32b is exposed to the outside of the heat conductive insulating member 58 and connected to the power line 33b. The positive terminal 32a of the secondary capacitor 32 is exposed to the outside from the heat conductive insulating member 58 and connected to the power line 33a.

  As shown in FIG. 3, the reactor 42, the primary capacitor 30, and the secondary capacitor 32 are arranged in this order along the direction away from the end 50 a side in the housing 50.

  The operation of the drive system 12 configured as described above will be described below in relation to the power conversion device 10 according to the first embodiment.

  In the DC / DC converter 20, when the lower arm element 36 is turned on, a circuit is formed by the battery 16, the reactor 42, and the lower arm element 36. For this reason, energy is stored in the reactor 42 according to the direct current flowing from the battery 16. When the lower arm element 36 is turned off in this state, the energy stored in the reactor 42 is stored in the secondary capacitor 32 via the diode 38. At that time, the DC voltage of the secondary capacitor 32 is set higher than the DC voltage of the battery 16.

  When the output voltage of the fuel cell 14 and the DC voltage of the secondary capacitor 32, that is, the secondary voltage of the DC / DC converter 20, are substantially the same or within a predetermined voltage difference range, A current is supplied from the fuel cell 14 to the drive motor 26 via the inverter 24.

  By the way, in the DC / DC converter 20 described above, since a large current flows to the primary side which is the low voltage side, the reactor 42 becomes high temperature, and the bus bar 44 connecting the reactor 42 and the primary side capacitor 30 also becomes high temperature. Easy to be. On the other hand, the primary capacitor 30 is easily affected by heat, and the heat-resistant temperature is set in advance.

  In this case, in the first embodiment, as shown in FIG. 4, the reactor 42, the primary side capacitor 30, and the secondary side capacitor 32 are arranged in the frame member 56, and these are integrated by the heat conductive insulating member 58. It is buried underground. And between the reactor 42 and the primary side capacitor | condenser 30, the thermal insulation member 60 for interrupting | blocking the heat conduction from the said reactor 42 to the said primary side capacitor | condenser 30 is arrange | positioned.

  For this reason, even if the reactor 42 and the primary side capacitor | condenser 30 are arrange | positioned adjacently, the said primary side capacitor | condenser 30 is not influenced by heat. Therefore, the size of the LC unit 52 is reduced, so that the entire power conversion device 10 is made compact, and the bus bar 44 that electrically connects the reactor 42 and the primary capacitor 30 is shortened as much as possible. As a result, the bus bar 44 can suppress the generation of noise and high temperature, and can prevent the primary side capacitor 30 from being affected.

  Further, inside the heat conductive insulating member 58, the heat conductive insulating member 58 on the primary capacitor 30 side and the heat conductive insulating member 58 on the reactor 42 side are integrated with the heat shield member 60 interposed therebetween. An integrated connecting portion 62 is provided, and a bus bar 44 is disposed in the integrated connecting portion 62. Therefore, with a simple configuration, the bus bar 44 can be satisfactorily cooled by the heat conductive insulating member 58 (integrated connecting portion 62), and the primary capacitor 30 can be reliably prevented from being affected by heat. The effect that it becomes possible is obtained.

  In addition, the end portion 60 a of the heat shield member 60 is separated from the exposed surface 58 a of the heat conductive insulating member 58 by a distance S. Therefore, the embedding operation is performed only by filling the thermal conductive insulating member 58 once with the reactor 42, the primary capacitor 30 and the secondary capacitor 32 disposed in the frame member 56. Thereby, there exists an advantage that workability | operativity improves favorably.

  Furthermore, the power conversion apparatus 10 includes a housing 50 that houses the switching module 41 and the LC unit 52, and a heat sink 54 is provided at an end 50a of the housing 50 (see FIG. 3). Therefore, the switching module 41 and the LC unit 52 can be cooled with a simple configuration.

  At that time, the switching module 41 is provided at the end 50a of the casing 50, and the reactor 42, the primary capacitor 30 and the secondary capacitor 32 that are likely to become hot along the direction away from the end 50a. Are arranged in the order. Thereby, it can cool favorably from the component which tends to become high temperature, and the improvement of cooling efficiency is achieved easily.

  Further, the minus terminals 30 b and 32 b of the primary side capacitor 30 and the secondary side capacitor 32 are made common inside the heat conductive insulating member 58, and a single negative terminal 30 b is used as the heat conductive insulating member 58. Exposed outside. Therefore, the number of terminals exposed to the outside is reduced, the number of assembly steps is reduced, and workability is improved.

  FIG. 5 is an explanatory cross-sectional view of the LC unit 72 constituting the vehicular power converter 70 according to the second embodiment of the present invention.

  In addition, the same referential mark is attached | subjected to the component same as the power converter device 10 which concerns on 1st Embodiment, and the detailed description is abbreviate | omitted. Similarly, in the third and fourth embodiments described below, detailed description thereof is omitted.

  The LC unit 72 is provided on the bottom 56 b of the frame member 56 between the reactor 42 and the primary capacitor 30 and provided with a heat shield member 74. The heat shield member 74 has a hole portion 76 opened inside the heat conductive insulating member 58, and an integrated connecting portion 78 is formed in the heat conductive insulating member 58 filled in the hole portion 76. .

  The hole 76 is provided at a location where the heat influence from the reactor 42 to the primary capacitor 30 is small, and the bus bar 44 is disposed in the thermally conductive insulating member 58 filled in the hole 76. The end 74a of the heat shield member 74 may be set at the same position as the exposed surface 58a of the heat conductive insulating member 58 or at a position protruding outward from the exposed surface 58a.

  In the second embodiment configured as described above, the reactor 42 and the primary capacitor 30 can be arranged as close as possible, and the bus bar 44 can be cooled well. For this reason, the effect similar to said 1st Embodiment is acquired.

  In addition, when the heat conductive insulating member 58 is filled, the heat conductive insulating member 58 is filled into the frame member 56 through a hole 76 formed in the heat shield member 74 by a single filling process. It becomes possible.

  FIG. 6 is an explanatory cross-sectional view of the LC unit 82 constituting the vehicular power converter 80 according to the third embodiment of the present invention.

  In the LC unit 82, the reactor 42, the primary side capacitor 30 and the secondary side capacitor 32 in the frame member 56 are different from the first and second embodiments, and are substantially rotated by 90 ° (horizontal From a posture to a vertical posture or vice versa.

  Thereby, in 3rd Embodiment, the direction of the reactor 42, the primary side capacitor | condenser 30, and the secondary side capacitor | condenser 32 can be changed, and it becomes possible to aim at the improvement of layout property while improving a freedom degree of shape. Become.

  Furthermore, in the primary side capacitor 30 and the secondary side capacitor 32, since the ESL (equivalent series inductance) reduction structure is adopted, the orientation of the arrangement can be determined flexibly.

  FIG. 7 is a schematic plan view illustrating a vehicle power converter 90 according to the fourth embodiment of the present invention.

  In the vehicle power conversion device 90, the switching module 41 of the DC / DC converter 20, the LC unit 52, and the switching module 92 for the inverter 24 are accommodated in the housing 50.

  Accordingly, in the fourth embodiment, since the DC / DC converter 20 and the inverter 24 are accommodated in the single casing 50, the entire power conversion device 90 is further reduced in size and the wiring work is simplified. Is achieved.

  The present invention is not limited to the above-described embodiment, and various configurations can be adopted without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10, 70, 80, 90 ... Power converter 12 ... Drive system 14 ... Fuel cell 16 ... Battery 18 ... Power feeding circuit 20 ... DC / DC converter 24 ... Inverter 26 ... Drive motor 30, 32 ... Capacitor 34 ... Upper arm element 36 ... Lower arm elements 41, 92 ... Switching module 42 ... Reactor 44 ... Bus bar 50 ... Housing 52, 72, 82 ... LC unit 54 ... Heat sink 56 ... Frame member 58 ... Thermally conductive insulating member 58a ... Exposed surface 60, 74 ... Heat shield members 50a, 60a, 74a ... End parts 62,78 ... Integral connecting part 76 ... Hole parts

Claims (7)

A vehicle power conversion device for converting power supplied from a power source and supplying the power to a drive motor,
A frame member is disposed in the housing, and the inside of the frame member is divided into one chamber and the other chamber by a projecting heat shield member,
A capacitor for smoothing the voltage is provided in the one chamber ,
A reactor is provided in the other chamber ,
The capacitor and the reactor are electrically connected through a connection path straddling the heat shield member, and the capacitor, the reactor, the heat shield member, and the connection path are integrally embedded in a heat conductive insulating member. by, integral connecting portion is formed between the capacitor and the front Symbol reactor,
A pair of terminals of the reactor are provided so as to protrude from the thermally conductive insulating member so as to face a switching module that is spaced apart in the casing . The power conversion device for a vehicle according to claim 1, wherein the heat shield member has an end portion that is internally spaced from an exposed surface of the thermally conductive insulating member,
The vehicle power converter according to claim 1, wherein the integrated connecting portion is formed between the exposed surface and the end portion. The power conversion device for a vehicle according to claim 1, wherein the heat shield member has a hole portion opened inside the thermally conductive insulating member,
The vehicle power converter according to claim 1, wherein the integrated connecting portion is formed in the thermally conductive insulating member filled in the hole. In the vehicle power converter device according to any one of claims 1 to 3 ,
At the end of the previous Kikatamitai vehicular power conversion apparatus characterized by a heat sink is provided. The power converter for a vehicle according to claim 4, wherein the switching module is provided at the end of the casing,
The power converter for a vehicle, wherein the reactor and the capacitor are arranged in this order along a direction away from the end side. The power converter for vehicles according to any one of claims 1 to 5, wherein the capacitor includes an input side capacitor and an output side capacitor of the switching module,
The vehicular power converter according to claim 1, wherein negative terminals of the input-side capacitor and the output-side capacitor are commonly used inside the thermally conductive insulating member.   The vehicle power converter according to any one of claims 1 to 6, wherein the reactor and the capacitor are provided on a lower voltage side than the switching module.

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