Rotor position estimation based on magnetic saliency of an IPM motor-realization of a wide-speed range from zero to the rated speed

This paper describes position estimation based on magnetic saliency of an interior permanent magnet synchronous motor (IPM motor) for the purpose of achieving a wide-speed range. The position estimation, which has been proposed by the authors, is characterized by the real-time algorithm estimating the rotor position at every PWM period. Selection of PWM patterns proposed in this paper expands the speed range capable of estimating the rotor position to a higher-speed range. The PWM patterns are switched over, depending on an amplitude and phase of the average output voltage vector. Experimental results obtained from an IPM motor drive system of 100 W demonstrate that the selection of the PWM patterns makes it possible to estimate the rotor position in a wide-speed range from zero to the rated speed.