Principles and implementation of permanent magnet synchronous motor zero-speed sensorless control

This paper presents an implementation of zero speed sensorless control for permanent magnet synchronous machines (PMSM). The paper focuses on the principles and practical implementation of high frequency injection technology in a salient PMSM. The method using rotating vector, carrier frequency excitation and heterodyning, tracking observers for position estimation is discussed. A DSP-based drive system for this purpose is developed. The experimental results for the case of a buried PM machine are shown in the paper. It was demonstrated that acceptable results could be obtained from the buried PM machine using the simplest, single saliency-tracking method and a digital solution (DSP system based) is feasible for low speed operation, including zero speed.