EKF-based sensorless IPM synchronous motor drive for flux-weakening applications

The paper deals with the experimental realisation of a sensorless interior permanent magnet (IPM) synchronous motor drive. The motor has been specifically designed to get a wide flux-weakening region, to minimise the drive power rating in spite of a wide speed range. Position and angular speed of the rotor are obtained through an extended Kalman filter (EKF). The estimation algorithm requires neither the knowledge of the mechanical parameters, nor the initial rotor position. In the paper, particular emphasis is placed on control algorithms, that are complicated by the motor anisotropy and that have been specifically studied to enhance the overall system performance.