Patent ID: 6404150
Filing Date: 2002-06-11
Classification: B60L,Y02T

Abstract:
An accessory motor drive power supply system for use in an electric vehicle to operate both brushless and brush-type DC motors from a high voltage bus, the motor drive power supply system comprising:a first DC-DC converter having a power input for receiving operating power from the high voltage bus, a first speed control input for receiving a first speed control signal indicative of desired motor speed, and an output for providing a motor drive signal; a brushless DC motor having a commutation circuit connected to said output of said first DC-DC converter; a second DC-DC converter having a power input for receiving operating power from the high voltage bus, a second speed control input for receiving a second speed control signal indicative of desired motor speed, and an output for providing a motor drive signal, and a brush-type DC motor connected to said output of said second DC-DC converter, wherein each of said first and second DC-DC converters is operable in response to the speed control signal received on its speed control input to convert operating power from the high voltage bus into a variable motor drive signal that is provided to its associated motor via its output, whereby speed control of each of said DC motors is carried out by a DC-DC converter operating off the high voltage bus.