An extended Kalman filter observer for the direct torque controlled interior permanent magnet synchronous motor drive

This work focuses on an accurate extended Kalman filter (EKF) observer, which estimates angular speed and position of the rotor, stator flux linkage and torque for interior permanent magnet synchronous motors (IPMSM), over a wide speed range including the very low speed region. The EKF observer provides recursive optimal state estimation of IPMSM, which is non-linear, time-variant, dynamical system in real time by using signals that are corrupted by noise. The EKF has robustness to parameter variations, model inaccuracy and measurement noises. Realistic simulations accounting for the inaccuracy of an actual digital signal processor (DSP) implementation are presented.