Stability analysis of MRAS speed sensorless control of permanent magnet synchronous motor

This paper presents stability analysis of Permanent Magnet Synchronous Motor (PMSM) sensorless control. In the sensorless control method, the stator current is measured to estimate the speed of the motor. To estimate the speed of the motor, we use Model Reference Adaptive System (MRAS) method as an observer. The Integral Proportional (IP) speed controller is used to control the system. The nonlinear system is linearized and expressed in state space form. To determine the stability of the system, it is necessary to find the eigenvalues of the matrix. The stability of the system is also analyzed using Bode stability criterion and Root Locus.