Analysis of Sensorless PMSM Drive with Adaptive Controller Tuning

Permanent Magnet Synchronous Motors (PMSMs) are widely used in industrial applications due to their robustness, precision and reliable performance. PMSMs are traditionally controlled using sensors for accuracy. However, the necessity for sensorless control has emerged to address the increased complexity, cost, and limited reliability issues of sensors. Sensorless techniques estimate the motor speed and position using motor current measurements, improving drive robustness and reducing maintenance needs. Extended back electromotive force (EMF) estimation is one of the techniques used to compute accurate rotor position and speed using motor voltages and currents. Sensorless drives utilize multiple controllers for speed, current control and back EMF estimation and it is crucial to choose the suitable bandwidth for these controllers. Motor parameter-based controller tuning, wherein motor parameters are used to compute controller coefficients is used to enable control system tuning for wide set of PMSMs. This paper discusses sensorless PMSM system modelling and implementation of motor parameter-based adaptive controller tuning. Furthermore, Extended back EMF estimation-based motor speed and position estimation technique implementation aspect is discussed. A generalized controller bandwidth selection procedure is presented to simplify the controller tuning process of sensorless PMSM drive. MATLAB/Simulink simulation model of the drive system is developed and result analysis is carried out to assess the system performance.