Shaft Position Correction Scheme Comparison for Sensorless Control of a PMSM Based on State-Space Estimation between Variance Adjustment and Angle PI Regulation

This paper investigates the impact of two main shaft position-error calibration techniques for sensorless operation of a permanent-magnet synchronous motor (PMSM) drive. Four state observers, the extended Kalman filter (EKF), the linear Kalman filter (LKF), the single dimension Luenberger (SDL) observer and the full-order Luenberger (FOLU) observer, are realized and compared with a basic flux-linkage observer (FLO) in aspects of estimated position precision and speed dynamic response. Experimental results show that the error correction type is the main deciding factor for the presented sensorless PMSM drive's performance of determining position and speed.