An Innovative High-speed Track Range Restart Strategy for Permanent Magnet Synchronous Motor

Abstract:
In speed sensorless motor drive systems, restarting a free-running motor requires knowledge of the instantaneous rotor position and motor speed. Those restart methods based on zero voltage pulses have been widely used. However, conventional restart methods are not suitable for those conditions with high ratational frequency and long current sample time. When motor operates at high speed the phase error between two consecutive short current may over 180 degrees, conventional zero voltage sequence will cause incorrect rotor speed and position estimation. The novelty of the proposed method in this paper is that it is suitable for both high rotaional frequency and low rotaional frequency and needs no machine paramters identification.