JP2011114872A - Power conversion apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power conversion apparatus that can be miniaturized and reduced in the number of parts. <P>SOLUTION: The power conversion apparatus 1 includes: a housing 10; a control board 12 having a high voltage detection circuit 64; a fixing screw 14 to fix the control board 12 to a housing 10 by being fastened to a fastening part 36 of a control board arranged at the housing 10; a screw insertion hole 66 arranged at the control board 12 for inserting the fixing screw 14; and a positive bus bar 16 for electrically connecting to a power supply. In the power conversion apparatus 1, an internal wiring 70 in the board electrically connects the screw insertion hole 66 to the high voltage detection circuit 64; the screw insertion hole 66 is constituted as a through-hole; and the positive bus bar 16 is electrically connected to the fixing screw 14. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a power converter having a high voltage bus bar connected to a high voltage DC power source.

  The power converter (inverter) detects the voltage of the high-voltage bus bar (high-voltage unit) connected to the high-voltage DC power supply using a high-voltage detection circuit (voltage detection circuit) provided on the control board, and controls drive based on the detection result. And self-protection control. Therefore, it is necessary to electrically connect the high-voltage bus bar and the control board.

  In recent years, the power conversion device has been downsized including the downsizing (reduction in area) of the heat dissipation board (corresponding to the first heat dissipation board 22 and the second heat dissipation board 26 shown in FIG. 1) on which power elements are provided. Is required. For this reason, it is necessary to electrically connect the high-voltage bus bar and the control board while reducing the size of the power converter. As a method of electrically connecting the high voltage bus bar and the control board while reducing the size of the power converter, there is a wire harness connection.

  As shown in FIGS. 4 and 5, the wire harness is connected to the connector of the control board 120 via the wire harness 118 from the terminal 116 attached to the branching tip 114 branched from the positive bus bar 112 provided in the housing 110. It joins to the joining part 122. The connector joint 122 is electrically connected to the high voltage detection circuit 126 via the board internal wiring 124. Thereby, the positive electrode bus bar 112 of the high voltage part and the high voltage detection circuit 126 of the control board 120 are electrically connected. Here, FIG. 4 is a top view of a part of the power conversion apparatus 101 to which the wire harness is connected, and FIG. 5 is a cross-sectional view taken along line BB of FIG.

  According to such a wire harness connection, the fixing screw 128 for fixing the control board 120 to the housing 110 can be provided in a space vacated by the handling of the positive bus bar 112 by branching, so that the size can be reduced.

  Further, in the power conversion device of Patent Document 1, a voltage sensor for measuring a voltage between the negative electrode bus bar and the metal case is provided on the control board, and the voltage sensor and the metal case are electrically connected by a metal plate. A method of connecting is disclosed.

JP 2008-301608 A

  However, in the wire harness connection, the wire harness 118, and in the connection method disclosed in Patent Document 1, another member such as a metal plate is separately required, and the number of parts increases. And the assembly process of the wire harness 118 and a metal plate will also increase excessively. Therefore, the manufacturing cost increases.

In order to cope with this problem, there is a terminal connection as a connection method for suppressing the number of parts.
For terminal connection, in addition to the power element connection terminal 132 at the terminal 130 of the housing 110, as shown in FIG. 6, a dedicated terminal 134 is provided, and the dedicated terminal 134 is connected to a heat radiating board (not shown) by a wire. Further, it is inserted into the terminal hole 136 of the control board 120 and joined by soldering. The terminal hole 136 is connected to the high voltage detection circuit 126 via the board internal wiring 124. Thereby, the positive electrode bus bar 112 of the high voltage part and the high voltage detection circuit 126 of the control board 120 are electrically connected. Here, FIG. 6 is a cross-sectional view of the power converter 102 that has been connected to the terminal.

  However, according to the terminal connection, it is necessary to enlarge the terminal 130 in order to provide the dedicated terminal 134, and to enlarge the heat dissipation board in order to connect to the dedicated terminal 134 with a wire, and thus the size of the power converter can be reduced. Absent. In addition, the manufacturing cost increases.

  Therefore, the present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power converter that can reduce the size of the device and reduce the number of components.

  One aspect of the present invention made to solve the above-described problems is that a housing, a control board provided with a control circuit, and a screw fastening portion provided in the housing are fastened to the control board. In a power converter having a fixing screw for fixing, a screw insertion hole provided in the control board for inserting the fixing screw, and a bus bar electrically connected to a power source, the screw insertion hole and the control circuit are electrically connected. The screw insertion hole is configured as a through hole, and the bus bar is electrically connected to the fixing screw.

  According to the present invention, there is a wiring for electrically connecting the screw insertion hole and the control circuit, the screw insertion hole is configured as a through hole, and the bus bar is electrically connected to the fixing screw. Therefore, the bus bar is electrically connected to the control circuit via a fixing screw, a screw insertion hole, and wiring. Therefore, according to the present invention, the fixing screw for fixing the control board to the housing and the screw insertion hole for inserting the fixing screw are also used for electrically connecting the bus bar and the control circuit. is doing. Therefore, it is possible to reduce the size of the device and reduce the number of parts.

  As one aspect of the present invention, the bus bar is provided in the screw fastening portion.

  According to this aspect, since the bus bar is provided at the screw fastening portion, the bus bar and the fixing screw are easily electrically connected by fastening the fixing screw to the bus bar, and the bus bar and the control circuit are electrically connected. Can be connected to.

  As one aspect of the present invention, the bus bar includes a main path portion that is electrically connected to the power source and a branch path portion that is branched from the main path portion and is electrically connected to the fixing screw. To do.

  According to this aspect, even if the position for connecting the power supply and the position for fastening the fixing screw are separated, the bus bar can be electrically connected to the control board while being electrically connected to the power supply.

  As one aspect of the present invention, the control circuit is a voltage detection circuit that detects a voltage of the bus bar.

  According to this aspect, the voltage of the bus bar can be detected by the voltage detection circuit electrically connected to the bus bar, and the power converter can be controlled based on the detected result.

  According to the power conversion device of the present invention, it is possible to reduce the size of the device and reduce the number of components.

It is a top view in a part of power converter of the present invention, and is a figure showing the state where a control board is not fixed to a housing. It is a top view in a part of power converter of the present invention, and is a figure showing the state where a control board was fixed to a housing. It is AA sectional drawing of FIG. It is a top view in a part of power converter which performed wire harness connection. It is BB sectional drawing of FIG. It is sectional drawing of the power converter device which performed terminal connection.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIGS. 1 and 2 are top views of a part of the power conversion apparatus of this embodiment. FIG. 1 shows a state in which the control board is not fixed to the housing, and FIG. 2 shows a state in which the control board is fixed to the housing. Is shown. FIG. 3 is a cross-sectional view taken along the line AA in FIG.

The power conversion device 1 of the present embodiment is used as an inverter in a hybrid vehicle, for example.
As shown in FIGS. 1 and 2, the power conversion device 1 includes a housing 10, a control board 12, a fixing screw 14, a positive (P) pole bus bar 16, a negative (N) pole bus bar 18, a first heat dissipation board 20, 1 power element 22, output bus bar 24, second heat dissipation substrate 26, second power element 28, and the like.

  The housing 10 is a case that houses the first power element 22 and the second power element 28 on the upper surface thereof. The first power element 22 and the second power element 28 are provided with an IGBT (Insulated Gate Bipolar Transistor), a diode (Free Wheel Diode), and the like that constitute an inverter circuit. In order to control a three-phase AC motor (not shown), the inverter circuit of the power converter 1 includes a set of semiconductor circuits including a first power element 22, an output bus bar 24, and a second power element 28 as shown in FIG. Although a total of three sets are provided in the left-right direction in FIG. 2, only one set of semiconductor circuits is shown in FIGS. 1 and 2.

  The first power element 22 and the second power element 28 are mounted on the first heat dissipation board 20 and the second heat dissipation board 26, respectively. Thereby, the heat generated in the first power element 22 and the second power element 28 is released from the first heat dissipation board 20 and the second heat dissipation board 26.

  In the space between the first heat dissipation substrate 20 and the second heat dissipation substrate 26, the positive electrode bus bar 16 and the negative electrode bus bar 18 are provided in parallel to each other along the arrangement direction in which the three sets of semiconductor circuits are provided. Yes. The positive electrode bus bar 16 and the negative electrode bus bar 18 are connected to a high voltage DC power source (not shown).

  In the present embodiment, the positive electrode bus bar 16 is branched, and includes a main path portion 30 connected to a high-voltage DC power supply (not shown) and a branch path portion 32 branched from the main path portion 30. At the tip of the main path portion 30, a power supply connection portion 34 that is a connection portion with a high-voltage DC power supply is provided. On the other hand, the branch path portion 32 is provided in an empty space of the housing 10, and its tip extends to the control board fastening portion 36. The control board fastening portion 36 is a portion that is provided in the housing 10 and fastens the fixing screw 14. A screw hole 38 for fastening the fixing screw 14 is formed at the tip of the branch path portion 32. Therefore, by fastening the fixing screw 14 having conductivity in the screw hole 38, the tip of the branch path portion 32 is electrically connected to the fixing screw 14, and the positive bus bar 16 is electrically connected to the fixing screw 14.

The output bus bar 24 includes a motor connection portion 40 connected to a three-phase AC motor (not shown) on one end side.
The positive bus bar 16 is connected to the first heat dissipation substrate 20 by a wire 42, and the first power element 22 is connected to the output bus bar 24 by a wire 44. The output bus bar 24 is connected to the second heat dissipation substrate 26 by a wire 46, and the second power element 28 is connected to the negative electrode bus bar 18 by a wire 48.

  The housing 10 is provided with a terminal 50, and the terminal 50 is provided with a power element connection terminal 54. The power element connection terminal 54 is connected to the electrode 58 of the first power element 22 and the electrode 60 of the second power element 28 by a wire 56. Further, the power element connection terminal 54 is inserted into a terminal hole 62 provided in the control board 12 and joined by soldering. The power element connection terminal 54 is connected to various control circuits provided on the control board 12 by wiring (not shown).

  The control board 12 is a board on which various control circuits such as the high voltage detection circuit 64 are provided. The high voltage detection circuit 64 is a circuit that detects the voltage of the positive bus bar 16 and performs drive control and self-protection control based on the detection result. Here, specifically, the drive control and the self-protection control stop the driving of the power element for the purpose of protecting the power converter 1 (inverter) when the voltage of the positive bus bar 16 exceeds a predetermined abnormal level. It is control which performs. Note that the position where the high voltage detection circuit 64 is provided is not limited to the position shown in FIG. 2, and may be arranged anywhere in the control board 12 as long as other various control circuits are not hindered.

As shown in FIG. 3, the control board 12 is provided with a screw insertion hole 66 into which the fixing screw 14 is inserted. Then, the control board 12 is fixed to the housing 10 by inserting the fixing screw 14 into the screw insertion hole 66 and fastening it to the screw hole 38 of the branch path portion 32 in the control board fastening portion 36.
The screw insertion hole 66 is a hole for inserting the fixing screw 14 and is a through hole whose inner surface is subjected to, for example, copper plating. The screw insertion hole 66 is electrically connected to the high voltage detection circuit 64 by the board internal wiring 70. The inner surface of the screw insertion hole 66 may be threaded or may not be threaded.

  In this embodiment, as shown in FIG. 3, the fixing screw 14 is inserted into the screw insertion hole 66 of the control board 12, and the screw hole 38 at the tip of the branch path portion 32 of the positive bus bar 16 provided in the control board fastening portion 36. It is concluded to. Thereby, the control board 12 can be fixed to the housing 10, and at the same time, the positive electrode bus bar 16 and the screw insertion hole 66 which is a through hole are electrically connected. The screw insertion hole 66 is electrically connected to the high-voltage detection circuit 64 through the board internal wiring 70. Therefore, the positive bus bar 16 is electrically connected to the high voltage detection circuit 64 via the fixing screw 14, the screw insertion hole 66, and the board internal wiring 70.

That is, in this embodiment, the fixing screw 14 for fixing the control board 12 to the housing 10 and the screw insertion hole 66 for inserting the fixing screw 14 are electrically connected to the positive bus bar 16 and the high voltage detection circuit 64. It is also used to connect. Therefore, the power converter 1 can be electrically connected to the high voltage side positive bus bar 16 and the high voltage detection circuit 64 of the control board 12 without increasing the size and increasing the number of components. Therefore, the number of parts can be reduced as compared with the prior art while reducing the size of the device including the size of the first heat dissipation substrate 20 and the second heat dissipation substrate 26, and the manufacturing cost of the power conversion device 1 can be reduced. Can be achieved.
Then, by electrically connecting the positive bus bar 16 and the high voltage detection circuit 64, the high voltage detection circuit 64 detects the voltage of the positive bus bar 16, and controls the power converter 1 based on the detected result. It can be carried out.

  Further, since the branch path portion 32 of the positive bus bar 16 is formed in the empty space of the housing 10 and is electrically connected to the fixing screw 14 at the tip of the branch path portion 32, the power converter 1 can be more reliably downsized. Can be achieved.

  The branch path portion 32 of the positive bus bar 16 is provided in the control board fastening portion 36. Therefore, the positive bus bar 16 and the fixing screw 14 are easily electrically connected by fastening the fixing screw 14 in the screw hole 38 of the branch path portion 32, and the positive bus bar 16 and the high voltage detection circuit 64 are electrically connected. Can be connected to.

  The positive bus bar 16 includes a main path portion 30 connected to the high-voltage DC power source and a branch path portion 32 branched from the main path portion 30 and electrically connected to the fixing screw 14. Therefore, even if the position for connecting the high-voltage DC power supply and the position of the control board fastening portion 36 for fastening the fixing screw 14 are separated, the high-voltage detection circuit of the control board 12 is electrically connected to the high-voltage DC power supply. 64 can also be electrically connected. Moreover, since the screw insertion hole 66 in the conventional power converter can be used, a new work such as drilling is not required, and the manufacturing cost can be suppressed. Furthermore, since the control board fastening portion 36 in the conventional power conversion device can be used, it is not necessary to secure a new place for electrically connecting the positive electrode bus bar 16 and the high voltage detection circuit 64, and the space on the housing 10. The manufacturing cost can be suppressed by effectively utilizing the above.

  It should be noted that the above-described embodiment is merely an example and does not limit the present invention in any way, and various improvements and modifications can be made without departing from the scope of the invention.

DESCRIPTION OF SYMBOLS 1 Power converter 10 Housing 12 Control board 14 Fixing screw 16 Positive electrode bus bar 18 Negative electrode bus bar 22 1st power element 24 Output bus bar 28 2nd power element 30 Main path part 32 Branch path part 36 Control board fastening part 38 Screw hole 42 Wire 54 Power element connection terminal 62 Terminal hole 64 High voltage detection circuit 66 Screw insertion hole 70 Internal wiring

Claims (4)

A housing, a control board provided with a control circuit, a fixing screw for fixing the control board to the housing by fastening to a screw fastening portion provided in the housing, and a fixing screw provided on the control board. In a power converter having a screw insertion hole to be inserted and a bus bar electrically connected to a power source,
A wiring for electrically connecting the screw insertion hole and the control circuit;
The screw insertion hole is configured as a through hole,
The bus bar is electrically connected to the fixing screw;
The power converter characterized by this. In the power converter device according to claim 1,
The bus bar is provided in the screw fastening portion;
The power converter characterized by this. In the power converter device according to claim 1 or claim 2,
The bus bar includes a main path portion connected to the power source and a branch path portion branched from the main path portion and electrically connected to the fixing screw;
The power converter characterized by this. In the power converter device of any one of Claims 1-3,
The control circuit is a voltage detection circuit for detecting a voltage of the bus bar;
The power converter characterized by this.

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