Sensorless control of a synchronous reluctance motor by finite elements model results

This paper concerns the development of a sensorless controller for synchronous reluctance motors based on finite elements model results. A hybrid solution is used, which includes an adaptive observer for not-zero speed operation and signal injection for standstill. The observer detects the flux linkages components in the two-phase stationary reference frame by the voltage model integration and closed loop correction feedback. This last is provided by a non-linear model of the rotor-fixed frame flux components achieved by finite elements computations. The rotor speed and position are identified by a phase-locked-loop algorithm. To improve the observer performance, the mechanical model is considered, which accounts for the finite elements mapping of the motor torque. The study is applied to a prototype of synchronous reluctance motor with flux barriers rotor, designed to have the same stator core of a commercial three-phase 3kW induction motor. Both realistic simulations (accounting for the non-linear machine behavior) and experimental test are presented, showing the performance of the proposed solution.