Sensorless Direct Torque Control of PMSM using Unsected Kalman Filter ⋆

Abstract: This paper considers the sensorless direct torque control of a Permanent Magnet Synchronous Motor (PMSM) by using Unscented Kalman Filtering (UKF) to estimate the flux-linkage, the rotor speed and the position. UKF adapts the unscented transformation (UT) algorithm and symmetrical sampling strategy. The UKF algorithm represents a serious strongpoint to the Extended Kalman Filter (EKF) for the highly nonlinear systems. UKF ensures high estimation precision and simple calculation. The sensorless Direct Torque Control (DTC) for PMSM is designed in this paper. The estimating errors when using UKF and EKF are compared. The effectiveness of this method is verified through several simulations. The DTC based on UKF for PMSM has good speed and torque response performances. This method has rapid astringency of estimated error