Power Inverter

• US 20130265808A1
• Filed: 12/22/2011
• Published: 10/10/2013
• Est. Priority Date: 12/27/2010
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Inventors: Fukumasu, Keisuke, Ishii, Akira
• Granted Patent: US 9,042,147 B2
• Time in Patent Office: Days
• US Class Current: 363/97
• CPC Class Codes: H02M 1/12 Arrangements for reducing harmonics from ac input or output
• CPC Class Codes: H02M 7/003 Constructional details, e.g. physical layout, assembly, wiring or busbar connections
• CPC Class Codes: H05K 7/14322 wherein the control and power circuits of a power converter are arranged within the same casing

Abstract

A power inverter includes a power semiconductor module that includes a power semiconductor device, a control circuit board that outputs a control signal used for controlling the power semiconductor device, a driver circuit board that outputs a driving signal used for driving the power semiconductor device, a conductive metal base plate arranged in a space between the driver circuit board and the control circuit board in which a fine and long opening portion is formed, wiring that connects the driver circuit board and the control circuit board through the opening portion and delivers the control signal to the driver circuit board, and an AC busbar that is arranged on a side opposite to the metal base plate through the driver circuit board and delivers an AC current output from the power semiconductor module to a drive motor. At least a portion of the AC busbar that faces the opening portion extends in a direction directly running in a longitudinal direction of the fine and long opening portion.

Claims

1. A power inverter comprising:

a power module that includes a power semiconductor device inverting a DC current into an AC current;

a control circuit board that outputs a control signal used for controlling the power semiconductor device;

a driver circuit board that outputs a driving signal used for driving the power semiconductor device based on the control signal;

a conductive base plate arranged in a space between the driver circuit board and the control circuit board in which a fine and long wiring opening portion is formed;

a control wiring that connects the driver circuit board and the control circuit board through the wiring opening portion and delivers the control signal to the driver circuit board; and

an AC busbar that is arranged on a side opposite to the base plate through the driver circuit board and delivers the AC current output from the power module to a drive motor,

wherein at least a portion of the AC busbar that faces the wiring opening portion extends in a direction perpendicular to a longitudinal direction of the fine and long wiring opening portion.

2. The power inverter according to claim 1, wherein

the AC busbar is configured by a U-phase AC busbar, a V-phase AC busbar, and a W-phase AC busbar used for allowing a three phase current to flow, and

the U-phase AC busbar, the V-phase AC busbar, and the W-phase AC busbar are formed such that at least portions facing the wiring opening portion are parallel to each other.

3. The power inverter according to claim 2, wherein

a sensor unit, which includes a magnetic core through which the AC busbar passes and a detection device detecting a magnetic flux density of the magnetic core, includes current sensors disposed for the U-phase, V-phase, and W-phase AC busbars, and

the current sensors are disposed at positions facing the wiring opening portion.

4. The power inverter according to claim 1, further comprising:

a conductive casing of a bottomed cylinder shape that has a casing opening portion closed by one face of the base plate and forms a housing space in which the driver circuit board is arranged; and

a conductive cover body that is fixed to the other face of the base plate and forms a housing space in which the control circuit board is arranged between the base plate and the cover body, wherein

the base plate is fixed to the casing such that the one face is brought into contact with a circumferential edge of the casing opening portion.

5. The power inverter according to claim 4, further comprising:

an external connector that includes a lead wiring used for being connected to the control circuit board, wherein

the external connector is arranged such that the lead wiring is connected to the control circuit board through a space between the control circuit board and the base plate.

6. The power inverter according to claim 5, wherein the wiring opening portion is arranged at a position facing one edge of the control circuit board, and the external connector is disposed on an edge located on a side opposite to the one edge of the control circuit board.

7. The power inverter according to claim 5, wherein

a wall portion surrounding a periphery of the control circuit board is integrally formed on the base plate, and

a housing space in which the control circuit board is arranged is formed by fixing the cover body to an upper end of the wall portion.

8. The power inverter according to claim 7, wherein a notch portion to which the external connector is fitted is formed on the wall portion.

9. The power inverter according to claim 4, further comprising:

an external connector that is electrically connected to the control circuit board;

an AC terminal to which the AC busbar is connected; and

a DC terminal that is used for supplying the DC current to the power module, wherein

the DC terminal and the AC terminal are arranged on a side face of one side of the casing, and

the external connector is arranged on a side face located on a side opposite to the side face of the casing.

10. The power inverter according to claim 9, further comprising:

a DC busbar that is connected to the DC terminal inside the casing, wherein

an extending direction of the DC busbar extending from the DC terminal is parallel to an extending direction of the AC busbar extending from the AC terminal.

11. The power inverter according to claim 4, further comprising:

a DC busbar that supplies the DC current to the power module, wherein

the base plate that closes the casing opening portion includes a first base plate area closing a part of the casing opening portion and a second base plate area closing the other part,

the control circuit board is arranged so as to face a cover body-side face of the first base plate area,

the driver circuit board is arranged so as to face a casing-side face of the first base plate area, and

the DC busbar is arranged so as to face a casing-side face of the second base plate area.