An Extended Kalman filter for sensorless direct torque controlled IPM synchronous motor drive

This paper investigates the application of an Extended Kalman Filter (EKF) for closed-loop flux, torque and speed estimation of a direct torque controlled (DTC) IPMSM drive over a wide speed range. The EKF provides a recursive optimum state estimation for IPMSMs using terminal signals that may be polluted by noise. Furthermore, the EKF has robustness to parameter variations, disturbance rejection capabilities and accurate estimation abilities. Experimental results verify the effectiveness of the proposed EKF observer for DTC of IPMSMs.