Sensorless Phase-Tracking Control System for Permanent-Magnet Synchronous Motors

Permanentmagnet (PM) motors have become increasingly popular owing to their use in many applications. PM motor drives require rotorposition sensors. Many techniques that do not involve the use of sensors have been developed for estimation the rotor position from voltage and current measurements.We proposed a novel sensorless control system for PM motor drives that did not require position estimation(3). The system can be easily constructed without using any motor parameters. The system works well over a wide speed-control range; from low to high speeds.In this paper, we describe in detail the principle underlying the proposed sensorless control system for PM motor drives and demonstrate the implementation of the system. Further we present experimental results that confirm the feasibility of the proposed control system.