MRAS Sensorless Control of the SynRM Based on a Simplified Finite Position Set Algorithm

Model reference adaptive system (MRAS) is one of the most popular methods in encoder less drive control applications due to its simple implementation. In the conventional MRAS method, there is a proportional-integral (PI) controller which estimates the motor speed by zeroing the error of the adaptive and the reference model. This method has problems such as pure integration effects and tuning the PI controller parameters at different operating points. This paper presents a MRAS speed estimator method based on a simplified finite position set iteration algorithm for a synchronous reluctance motor (SynRM). This method is inspired by the finite control set model predictive control (FCS-MPC) method, which calculates the optimal angle of the rotor by minimizing a cost function for a limited number of the rotor position in every sampling time. By using the proposed iteration algorithm, in addition to solving the problems caused by the PI controller in the conventional method, due to having low iterations compared to the algorithms of the other methods, it applies a minimal computational load to the microcontroller. The performance of the suggested method for SynRM in a wide range of speeds is simulated in MATLAB software.