Method for calibrating a motor control circuit to improve temperature measurement in an electrical motor

Abstract

A method enables adjustment of a current sense voltage for accurate measurement of an operating temperature for an electrical motor. The method includes identifying a DC input voltage to a motor winding and a duty cycle corresponding to the DC input voltage, the duty cycle being identified with reference to a linear relationship between two inverter loss factors established for different DC input voltages within a range of voltages for the DC input voltage. A voltage across the motor winding is identified with reference to the identified duty cycle, the identified voltage not including voltage dropped across an inverter used to apply the DC input voltage to the motor winding. The identified voltage across the motor winding is used to identify a resistance change for the motor winding.

Dependencies are inferred from the claim text.