Patent ID: 6100660
Filing Date: 2000-08-08
Classification: B60L,H02P,Y02T

Abstract:
A current supply controller for an electric motor comprising:a switching element (12a, 12b; 13a, 13b; 14a, 14b) opening and closing a current supply line from a power supply to the motor (11),a current sensor (15, 16, 17) detecting an actual driving current of the motor,a temperature sensor (19, 20, 21) located close to the switching element,first means (22) for generating and outputting an instruction value of the driving current of the motor on the basis of a signal representing a requested power output of the motor and a signal representing a temperature sensed by the temperature sensor, andsecond means (23, 24, 25) for driving the switching element to turn the switching element ON and OFF so as to bring a value representing the actual driving current of the motor detected by the current sensor close to the instruction value of the driving current generated by the first means,wherein the first means decides a target value (It) of the driving current on the basis of a signal representing a requested power output of the motor so as to achieve the requested power output and an allowable value (Ip) of the driving current on the basis of the temperature sensed by the temperature sensor, that is a maximum value of the driving current which can be supplied to the switching element without heat breakdown of the switching element, the first means outputs the target value (It) of the driving current as an instruction value of the driving current when the target value (It) of the driving current is smaller than the allowable value (Ip) of the driving current, and the first means outputs the allowable value (Ip) of the driving current as an instruction value of the driving current when the target value (It) of the driving current is greater than the allowable value (Ip) of the driving current.