Ralph L Benson

US Patent:

53695402, Nov 29, 1994

Filed:

Feb 11, 1993

Appl. No.:

8/016777

Inventors:

Charles E. Konrad - Roanoke VA
Ralph A. Benson - Roanoke VA

Assignee:

General Electric Company - Schenectady NY

International Classification:

H02H 700

US Classification:

361 6

Abstract:

A drive train for an electric vehicle includes a traction battery, a power drive circuit, a main contactor for connecting and disconnecting the traction battery and the power drive circuit, a voltage detector across contacts of the main contactor, and a controller for controlling the main contactor to prevent movement of its contacts to the closed position when the voltage across the contacts exceeds a predetermined threshold, to thereby protect the contacts of the contactor. The power drive circuit includes an electric traction motor and a DC-to-AC inverter with a capacitive input filter. The controller also inhibits the power drive circuit from driving the motor and thereby discharging the input capacitor if the contacts are inadvertently opened during motoring. A precharging contactor is controlled to charge the input filter capacitor prior to closing the main contactor to further protect the contacts of the main contactor.