Sensorless Control of PMSM via Extended State Interconnected Observer

The asymptotic tracking control problem is addressed for sensorless permanent magnet synchronous motor (PMSM) with unknown time varying load torque and stater resistence. A new interconnected observer is constructed to estimate the motor speed, position and system uncertain parameters with only the stator currents and input voltage are available. A nonlinear backstepping control algorithm based on the observer signals is designed and the stability of system is guaranteed.