CONTROL APPARATUS FOR ROTARY ELECTRIC MACHINES

• US 20120068644A1
• Filed: 09/16/2011
• Published: 03/22/2012
• Est. Priority Date: 09/17/2010
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: TSUJI, Hiroya
• Granted Patent: US 8,779,706 B2
• Time in Patent Office: Days
• US Class Current: 318/400.21
• CPC Class Codes: B60L 2240/526 Operating parameters
• CPC Class Codes: B60L 3/003 relating to inverters
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60L 7/003 Dynamic electric braking by short circuiting the motor
• CPC Class Codes: H02P 29/0243 the fault being a broken phase
• CPC Class Codes: H02P 3/22 by short-circuit or resistive braking
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility

Abstract

A control apparatus for a rotary electric machine has a DC-AC converting circuit with high- and low-potential-side switching elements to compose an inverter. In this apparatus, a connecting/disconnecting circuit is arranged to be electrically opened and closed between the DC-AC converting circuit and a power supply. A determining member determines whether or not the high-potential-side and low-potential-side switching elements have a malfunction. A failsafe performing element opens the connecting/disconnecting circuit and turns on both the high-potential-side and low-potential-side switching elements residing in a part of the inverter, when it is determined that there is caused a malfunction in the switching elements. The turned-on high-potential-side and low-potential-side switching elements realizes a short-circuit state therein.

Claims

1. A control apparatus for a rotary electric machine with terminals receiving power from a DC power supply with positive and negative output terminals, comprising;

a DC-AC converting circuit provided with serially connected circuits each having a high-potential-side switching element and a low-potential-side switching element, the high-potential-side and low-potential-side switching elements selectively connecting the terminals of the rotary electric machine to the positive and negative output terminals of the power supply for controlling a controlled variable of the rotary electric machine;

a connecting/disconnecting circuit arranged to be electrically opened and closed between the DC-AC converting circuit and the power supply to electrically connect and disconnect an electric path connecting both the DC-AC converting circuit and the power supply;

determining means that determines whether or not the high-potential-side and low-potential-side switching elements have a malfunction; and

failsafe performing means that opens the connecting/disconnecting circuit and turns on both the high-potential-side and low-potential-side switching elements residing in a part of the serially connected circuits when it is determined by the determining means that the high-potential-side and low-potential-side switching elements have the malfunction such that the turned-on high-potential-side and low-potential-side switching elements realize a short-circuit state therein.

2. The control apparatus of claim 1, comprising estimating means that estimates, among the switching elements, a switching element which has caused the malfunction therein,

wherein the failsafe performing means includes means for turning on a switching element electrically connected in series to the switching element estimated by the estimating means.

3. The control apparatus of claim 2, wherein the failsafe performing means includes means for turning on both the high-potential-side and low-potential-side switching elements which compose only one of the serially connected circuits, the one serially connected circuit being short-circuited.

4. The control apparatus of claim 3, wherein

the rotary electric machine is mounted on a vehicle provided with the rotary electric machine, a main machine, a low-voltage power supply whose output voltage is lower than output voltage of the DC power supply, and a step-down converter which steps down the output voltage of the DC power supply and supplies the step-down voltage to the low-voltage power supply, the switching elements of the DC-AC converting circuit being turned on and off based on power from the low-voltage power supply and the main machine being controlled based on the power from the low-voltage power supply;

and

the step-down converter is electrically connected to the DC power supply via the connecting/disconnecting circuit.

5. The control apparatus of claim 2, wherein the failsafe performing means includes means for turning on both the high-potential-side and low-potential-side switching elements which compose only one of the serially connected circuits, the one serially connected circuit being short-circuited,

6. The control apparatus of claim 5, wherein

the rotary electric machine is mounted on a vehicle provided with the rotary electric machine, a main machine, a low-voltage power supply whose output voltage is lower than output voltage of the DC power supply, and a step-down converter which steps down the output voltage of the DC power supply and supplies the step-down voltage to the low-voltage power supply, the switching elements of the DC-AC converting circuit being turned on and off based on power from the low-voltage power supply and the main machine being controlled based on the power from the low-voltage power supply;

and

the step-down converter is electrically connected to the DC power supply via the connecting/disconnecting circuit.

7. The control apparatus of claim 1, wherein

the rotary electric machine is mounted on a vehicle provided with the rotary electric machine, a main machine, a low-voltage power supply whose output voltage is lower than output voltage of the DC power supply, and a step-down converter which steps down the output is voltage of the DC power supply and supplies the step-down voltage to the low-voltage power supply, the switching elements of the DC-AC converting circuit being turned on and off based on power from the low-voltage power supply and the main machine being controlled based on the power from the low-voltage power supply;

and

the step-down converter is electrically connected to the DC power supply via the connecting/disconnecting circuit.