Full speed range sensorless control of permanent magnet synchronous machines for EV and HEV applications: state of the art

Abstract

This paper reviews the most significant rotor speed and position estimation methods for Permanent Magnet Synchronous Machines (PMSM). Additionally, the paper discusses their suitability for Electric Vehicle (EV) and Hybrid Electric Vehicle (HEV) applications. Two types of sensorless strategies are studied: (a) Back-Electromotive Force (Back-EMF) voltage estimation based strategies and (b) signal injection techniques. For practical purposes, an hybrid sensorless algorithm combining the High Frequency Injection (HFI) technique for low speed regions and standstill, and the Extended Kalman Filter (EKF) based solution for medium and high speed regions has been implemented. Finally, an accurate simulation model containing the power electronics converter, the current control algorithm as well as the hybrid sensorless strategy has been designed. Sensorless simulation results are given, which corroborates the validity of the chosen technique.