Sensorless Control for PMSM Using Model Reference Adaptive Control and back -EMF Sliding Mode Observer

This article presents a sensorless control structure for a PMSM (Permanent Magnet Synchronous Motor), with a MRAC (Model Reference Adaptive Controller) type speed controller, FOC (Field Oriented Control) type overall control strategy, and d-q axis type reference system, for which the Id current reference set to zero is selected for reasons of torque maximization, and the current reference is supplied by the MRAC adaptive controller output. The rotor speed and position are provided by a back-EMF (back electromotive force) sliding mode observer. The numerical simulations results obtained in the case of parameter variation and rapidly varying load torque with a random component, plus an adjustment mechanism described by first-order differential equations recommend the implementation of this structure in an embedded system in real time.