JP2019103285A - Power conversion device - Google Patents

Abstract

To improve noise resistance performance while suppressing upsizing of a power conversion device.SOLUTION: A power conversion device comprises a power semiconductor module including a power terminal, a smoothing capacitor including a capacitor terminal, a filter circuit, a case housing the power semiconductor module and the filter circuit, and a first wall. When viewed from a right angle direction with respect to an arrangement direction of the filter circuit and the smoothing capacitor, the power semiconductor module is arranged at a position at which it overlaps the filter circuit, the power terminal is provided in the first space between the filter circuit and the power semiconductor module, the capacitor terminal is extended to the first space and connected to the power terminal via the connection unit provided in the first space, and the first wall is arranged between the connection unit and the filter circuit and connected to the case.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power converter, and more particularly to a power converter for a hybrid car and an electric car.

  In an electric car or a hybrid car, a power conversion device for driving a traveling rotary electric machine by the power of a battery is mounted. In power converters for electric vehicles or hybrid vehicles, there is a strong demand for downsizing of the devices from the viewpoint of securing a living space and the like.

  With the miniaturization of the device, parts are integrated, and it becomes necessary to suppress the propagation of noise that may be transmitted and received between the parts.

  Although there are cases where a conductive shielding wall is used to suppress the noise propagation, it is required to suppress the increase in size of the power conversion device even when this shielding wall is used.

JP, 2013-031330, A

  An object of the present invention is to improve noise resistance performance while suppressing an increase in size of a power conversion device.

  A power conversion device according to the present invention includes a power semiconductor module which converts direct current power into alternating current power and has a power terminal, a smoothing capacitor which smoothes the direct current power and has a capacitor terminal, and parts different from the smoothing capacitor. A filter circuit, a case for housing the power semiconductor module and the filter circuit, and a first wall formed separately from the case, in the arrangement direction of the filter circuit and the smoothing capacitor The power semiconductor module is disposed at a position overlapping the filter circuit when viewed from the right angle direction, and the power terminal is provided in a first space between the filter circuit and the power semiconductor module, and the capacitor terminal Is extended to the first space and provided via the connection provided in the first space. Which is connected to the power terminal, wherein the first wall is connected to the arranged and the casing between said connecting portion and the filter circuit.

  According to the present invention, it is possible to improve the noise resistance performance while suppressing the increase in size of the power conversion device.

FIG. 5 is an enlarged perspective view of the vicinity of a connection portion between a power semiconductor module 300 and a smoothing capacitor 200 according to the present embodiment. It is an exploded perspective view of a power converter concerning this embodiment. FIG. 3 is a perspective view of a state in which the power conversion device of FIG. 2 is assembled and attached to a motor. It is sectional drawing of the power converter device and motor seen from the orthogonal direction of the surface 701 of FIG. FIG. 5 is an enlarged cross-sectional view of the vicinity of the filter circuit 103, the smoothing capacitor 200, and the power semiconductor module 300 in FIG. FIG. 4 is a cross-sectional perspective view of the power conversion device, the cross-section of which is cut along a plane 701 when FIG. 3 is viewed from a second direction 801; FIG. 16 is an overall perspective view of the power conversion layer, as viewed from an angle at which the terminal connection portion of the first space 700 is visible, except for the filter circuit 103. FIG. 16 is an overall perspective view of the power conversion device, in which the filter circuit 103 is incorporated in a case 400, and the terminal connection portion of the first space 700 is viewed from a visible angle. FIG. 6 is an overall perspective view showing a state in which the filter case 102 is attached to the case 400. It is an exploded perspective view of smoothing capacitor 200 concerning this embodiment. It is the perspective view which assembled | assembled the exploded perspective view of the smoothing capacitor 200 of FIG. FIG. 6 is a perspective view of a drive circuit board 501 and a control circuit board 502 for driving and controlling the power semiconductor module 300 assembled to a base portion 500. FIG. 12 is an exploded perspective view of a substrate circuit 503 shown in FIG.

  Embodiments of the present invention will be described using the drawings.

  FIG. 2 is an exploded perspective view of the power conversion device according to the present embodiment.

  DC connector 403 receives DC power from the battery and transmits the DC power to filter circuit 103. The direct current connector 403 is disposed on the side of the case 400.

  The filter circuit 103 removes electromagnetic noise included in DC power supplied from the DC power supply, and transmits the DC power to the smoothing capacitor 200. The filter circuit 103 includes a filter capacitor 100, a filter bus bar 101, and a filter cover 102.

  Filter capacitor 100 receives DC power from filter bus bar 101, and functions as a low pass filter for removing electromagnetic noise included in the DC power.

  Filter bus bar 101 receives DC power from DC connector 403, and transmits DC power from which electromagnetic noise has been removed by filter capacitor 100 to smoothing capacitor 200.

  The smoothing capacitor 200 has a function of absorbing the pulsating current of the DC power, reducing the pulsating component, and smoothing the current. The power semiconductor module 300 converts DC power into AC power.

  The case 400 includes a DC connector 403, a filter circuit 103, a substrate circuit 503, a power semiconductor module 300, an AC terminal 405, a smoothing capacitor 200, a discharge resistor 402, and a low voltage side connector 404. Prepare.

  The top cover 401 closes the opening on the upper surface side of the case 400 and protects the components in the case 400 as a lid. The discharge resistor 402 has a function of making the capacitor in the circuit non-charged and non-charged.

  The low voltage side connector 404 receives a signal from the outside and transmits the signal to a substrate circuit 503 described later. AC terminal 405 receives DC power from power semiconductor module 300 and transmits it to the motor. The water channel pipes 406 a and 406 b constitute a flow path for the refrigerant to flow. Undercover 408 blocks the opening on the lower surface side of case 400 and protects smoothing capacitor 200.

  FIG. 3 is a perspective view of a state in which the power conversion device of FIG. 2 is assembled and attached to a motor.

  The power conversion device according to the present embodiment is a mechanical-electrical integrated power conversion device in which a motor is disposed below. The motor case 600 has a substantially cylindrical shape in accordance with the cylindrical shape of the stator. In the power conversion device according to the present embodiment, a case portion 400C in which the smoothing capacitor 200 is housed is formed to project to the motor side along the curved surface portion of the cylinder of the case 600.

  This configuration allows the use of the space around the cylindrical case 600 to shorten the main electrical path without interference with the motor. As a result, the mechanical-electrical integrated structure can be miniaturized, and the effect of reducing the risk of electromagnetic noise received by the main electrical path can also be obtained.

  FIG. 4A is a cross-sectional view of the power conversion device and the motor viewed from the perpendicular direction of the surface 701 of FIG. 3.

  The filter core 104 has high impedance to high frequency current, and functions as a low pass filter to remove electromagnetic noise included in DC power. The filter core 104 penetrates the filter bus bar 101.

  The first direction 800 represents the arrangement direction of the filter circuit 103 and the smoothing capacitor 200. The third direction 802 represents a direction perpendicular to the first direction 800.

  When viewed from the third direction 802, the power semiconductor module 300 is disposed at a position overlapping the filter circuit 103. This arrangement has the effect of shortening the main electrical path of the smoothing capacitor 200 and the power semiconductor module 300.

  The first space 700 is provided between the filter circuit 103 and the power semiconductor module 300. In the first space 700, the capacitor terminal 209 illustrated in FIG. 9 and the power terminal 301 illustrated in FIG. 1 are joined by welding.

  The filter cover 102 blocks electromagnetic noise generated from the power semiconductor module 300 and protects the filter capacitor 100 and the filter bus bar 101 from electromagnetic noise. The filter cover 102 is removable from the case 400. Thereby, in the first space 700, when the filter cover 102 is removed, welding of the condenser terminal 209 and the power terminal 301 in an extremely narrow space where welding is difficult becomes easy.

  FIG. 1 is an enlarged perspective view around a connection portion between a power semiconductor module 300 and a smoothing capacitor 200 according to the present embodiment.

  The first wall 105 is formed as part of the filter case 102 in the present embodiment. The first wall 105 is provided between the filter circuit 103 and the first space 700 in a plane parallel to the first direction 800 described in FIG. 4A.

  Power terminal 301 is arranged on the side of power semiconductor module 300 to receive DC power from smoothing capacitor 200.

  FIG. 4B is an enlarged cross-sectional view of the filter circuit 103, the smoothing capacitor 200, and the power semiconductor module 300 in FIG. 4A.

The direct current bus bar 210 is connected to an insulating member in contact with the bottom of the case 400 to improve heat dissipation. The first contact portion 411 is a contact portion between the DC bus bar 210 and the bottom of the case 400.
The first heat radiation path 412 is located between the first contact portion 411 and the power module semiconductor 300. The heat generated in the DC bus bar 210 is transmitted from the first contact portion 411 to the first heat radiation path 412 along the sixth direction 805, transmitted from the first heat radiation path 412 to the cooling water channel of the power module semiconductor 300, and dissipated. Ru.

  FIG. 5 is a cross-sectional perspective view of the power conversion device in which the cross section is taken along plane 701 when FIG. 3 is viewed from the second direction 801.

  The case 400 forms a first through hole 703 in a portion facing the first space 700 shown in FIG. 4A. The capacitor terminal 209 is extended to the first space 700 via the first through hole 703.

  The connector side shielding wall 431 is integrally formed on the case 400. The connector side shielding wall 431 is formed integrally with the case 400, and has an effect of reducing the number of parts and an effect of suppressing a decrease in productivity.

  Further, the connector side shielding wall 431 is provided in a space in the case 400 other than the first space 700, surrounding the connector connection portion for connecting the low voltage side connector 404.

  The connector side shielding wall 431 functions as a ground of the control circuit board 502. The noise contained in the signal that the low voltage side connector 404 receives from the outside is absorbed by the capacitor provided in the connector connection portion in the connector side shielding wall 431.

  FIG. 6 is an overall perspective view of the power conversion layer where the terminal junction portion of the first space 700 is viewed from a visible angle except for the filter circuit 103. FIG. 8 is an overall perspective view showing the filter case 102 attached to the case 400. As shown in FIG.

  The screw fastening portion 201 constitutes an electrical connection portion between the filter circuit 103 and the smoothing capacitor 209.

  The filter circuit arrangement space 409 is formed by the filter case 102 including the upper surface portion 106 and the first wall 105 shown in FIG. 8 and a part of the connector side shielding wall 431 shown in FIG.

  The screw fastening portion 201 protrudes from the hole 410 provided at the bottom of the filter circuit storage space 409 toward the filter circuit disposition space 409.

  FIG. 7 is an overall perspective view of the power conversion device in which the filter circuit 103 is incorporated in the case 400 and the terminal connection portion of the first space 700 is viewed from a visible angle.

  In the first space 700, bonding between the terminals is made in the following process.

  As a first step, the power module semiconductor 300 and the smoothing capacitor 200 are assembled.

  As a second step, the welding surfaces of the power terminal 301 and the capacitor terminal 209 face each other in the first space 700.

  In the third step, a welding jig is placed in the first space 700, and the power terminal 301 and the capacitor terminal 209 are held in close contact with and fixed to the welding surface.

  As a fourth step, arc welding is performed from directly above the power terminal 301 and the capacitor terminal 209 to join the two terminals.

  FIG. 9 is an exploded perspective view of the smoothing capacitor 200 according to the present embodiment. FIG. 10 is a perspective view in which the exploded perspective view of the smoothing capacitor 200 of FIG. 9 is assembled.

  The direct current bus bar 210 is configured by the positive electrode side direct current bus bar 202 and the negative electrode side direct current bus bar 203. The positive side DC bus bar 202 receives DC power from the filter circuit 103 and transmits it to the smoothing capacitor cell 206. The smoothing capacitor cell 206 is a key component of the smoothing capacitor 200.

  The smoothing capacitor cell 206 absorbs and reduces the pulsating current component contained in the power.

  The positive side DC bus bar 202 receives the smoothed current from the smoothing capacitor cell 206 and transmits it to the power semiconductor module 300.

  Negative electrode side direct current bus bar 203 receives current from power semiconductor module 300 and transmits it to smoothing capacitor cell 206. The smoothing capacitor cell 206 transmits this current to the filter circuit 103.

  The smoothing capacitor case 204 accommodates the smoothing capacitor cell 206. After the smoothing capacitor cell 206 is housed in the smoothing capacitor case 204, the smoothing capacitor cover 205 closes the opening at the top of the smoothing capacitor case 204 to protect the smoothing capacitor cell 206. The smoothing capacitor cover 205 mainly uses a filler made of resin.

  The capacitor terminal 209 includes a positive electrode capacitor terminal 207 provided on the positive electrode DC bus bar 202 and a negative electrode capacitor terminal 208 provided on the negative electrode DC bus bar 203. The positive side capacitor terminal 207 and the negative side capacitor terminal 208 are portions that are respectively joined to the power terminal 301 by welding.

  The DC bus bar 210 receives heat from the power semiconductor module 300 and the DC bus bar 210 itself generates heat. The DC bus bar 210 is thermally connected to the bottom surface of the case 400 via the insulating member in order to improve the heat dissipation of the DC bus bar 210 while integrating the power conversion device integrally formed with the motor. Heat is dissipated.

  FIG. 11 is a perspective view in which a drive circuit board 501 and a control circuit board 502 for driving and controlling the power semiconductor module 300 are assembled to a base portion 500. FIG. FIG. 12 is an exploded perspective view of the substrate circuit 503 shown in FIG.

  The control circuit board 502 is a circuit board that generates a signal for controlling the switching drive of the power semiconductor module 300. The drive circuit board 501 is a circuit board that converts the switching drive signal received from the control circuit board 502 and transmits the converted signal to the power semiconductor module 300 to perform switching drive. The base portion 500 is provided between the drive circuit board 501 and the control circuit board 502.

  The fourth direction 803 represents the direction in which the drive circuit board 501 is disposed on the base unit 500. The fifth direction 804 represents the direction in which the control circuit board 502 is disposed on the base unit 500.

  The shape 505 is composed of a recess 505 a formed when viewed from the fourth direction 803 and a protrusion 505 b formed when viewed from the fifth direction 804.

  The base portion 500 is provided with a recess 505 a on the side where the drive circuit board 501 is disposed, which forms a space for housing a circuit component 504 such as a microcomputer and a power supply circuit portion.

  Further, the base portion 500 forms a convex portion 505b corresponding to the concave portion 505a on the side where the control circuit board 502 is disposed. The control circuit board 502 forms a through hole 506 for housing a part of the convex portion 505 provided in the base portion 500.

  The shape 505 has an effect of reducing the distance between components of the drive circuit substrate 501, the base portion 500, and the control circuit substrate 502 in the fourth direction 803 when the drive circuit substrate 501 and the control circuit substrate 502 are assembled to the base portion 500. .

  The discharge resistor 402 is disposed in the base unit 500 from the fourth direction 803. Thus, the base portion 500 functions as a heat radiation path when the temperature of the discharge resistor 402 rises.

DESCRIPTION OF SYMBOLS 100 ... Filter capacitor, 101 ... Filter bus bar, 102 ... Filter cover, 103 ... Filter circuit, 104 ... Filter core, 105 ... 1st wall, 106 ... Upper surface part, 200 ... Smoothing capacitor, 201 ... Screw fastening part, 202 ... Positive electrode Side DC bus bar 203: negative electrode side DC bus bar 204: smoothing capacitor case 205: smoothing capacitor cover 206: smoothing capacitor cell 207: positive electrode side capacitor terminal 208: negative electrode side capacitor terminal 209: capacitor terminal 210: 210 DC bus bar, 300: power semiconductor module, 301: power terminal, 400: case, 400C: case portion, 401: top cover, 402: discharge resistance, 403: DC connector, 404: low voltage side connector, 405: AC terminal, 406a ... waterway pie , 406b: water channel pipe, 408: undercover, 409: filter circuit arrangement space, 410: hole, 411: first contact portion, 412: first heat radiation path, 431: connector side shielding wall, 500: base portion, 501: ... Drive circuit board 502: control circuit board 503: board circuit 504: circuit component 505: shape: 505a: concave portion 505b: convex portion 506: through hole 600: motor case 700: first space 703: first through hole, 800: first direction, 802: third direction, 803: fourth direction, 804: fifth direction, 805: sixth direction

Claims (7)

A power semiconductor module for converting direct current power into alternating current power and having a power terminal;
A smoothing capacitor for smoothing the DC power and having a capacitor terminal;
A filter circuit composed of parts different from the smoothing capacitor;
A case for housing the power semiconductor module and the filter circuit;
And a first wall formed separately from the case.
When viewed in a direction perpendicular to the arrangement direction of the filter circuit and the smoothing capacitor, the power semiconductor module is disposed at a position overlapping the filter circuit,
The power terminal is provided in a first space between the filter circuit and the power semiconductor module.
The capacitor terminal is extended to the first space and connected to the power terminal through a connection provided in the first space.
The said 1st wall is a power converter device arrange | positioned between the said connection part and the said filter circuit, and being connected to the said case. A power converter according to claim 1, wherein
The smoothing capacitor is disposed at a position facing the filter circuit across the bottom of the case,
The bottom portion forms a first through hole in a portion facing the first space,
The power conversion device, wherein the capacitor terminal is extended to the first space via the first through hole. The power converter according to claim 2, wherein
The said converter terminal is a power converter device connected to the insulation member which contacts the said bottom part. The power converter according to any one of claims 1 to 3, wherein
A control connector for transmitting a signal related to the switching operation of the power semiconductor module;
The case includes a connector connection portion for connecting the control connector, and a connector side shielding wall which surrounds the connector connection portion and is provided in a space in the case other than the first space.
The connector side shielding wall is a power conversion device integrally formed in the case. The power converter according to claim 4, wherein
The power converter which forms the space where the said filter circuit is arrange | positioned by a part of said 1st wall and the said connector side shielding wall. The power converter according to any one of claims 1 to 5, wherein
A drive circuit substrate for outputting a drive signal to the power semiconductor module;
A control circuit board that outputs a control signal for controlling the power semiconductor module;
A base portion provided between the drive circuit board and the control circuit board;
The drive circuit board is provided with circuit components on the base portion side.
The base portion is provided on the side where the drive circuit board is disposed, in a recess that forms a space for storing a part of the circuit component, and on the side where the control circuit board is disposed, corresponding to the recess. Form a raised portion,
The said control circuit board is a power converter which forms the through-hole which accommodates a part of said convex part. The power converter according to any one of claims 1 to 5, wherein
A drive circuit substrate for outputting a drive signal to the power semiconductor module;
A control circuit board that outputs a control signal for controlling the power semiconductor module;
A base portion provided between the drive circuit board and the control circuit board;
A discharge resistor for discharging the charge of the smoothing capacitor;
The discharge resistor is disposed on the surface of the base portion on the side where the drive circuit substrate is disposed,
The said base part is a power converter device connected to the said case.

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