Circuit configuration and performance of a position-sensorless IPM motor drive system

This paper deals with a position-sensorless IPM motor drive system in which rotor position is estimated from current ripples generated by a PWM inverter. The new circuit configuration of a proposed digital controller makes it possible to reduce number of sample and hold circuits compared with the conventional system and to acquire current ripples automatically. Some experimental results show accuracy, response, and generality of the digital controller, and demonstrates a quick discrimination of magnetic polarity.