Sensorless IPM synchronous motor using high order sliding mode technique with finite time rotor position observer

In this paper robust nonlinear observer and controller are designed for sensorless control of interior permanent magnet synchronous motor (IPMSM). The proposed method is based on the high order sliding mode technique. The super twisting algorithm is combined with an interconnected observer which allows using it in multi-input multi output case. The proposed controller computed using the MTPA strategy ensures finite-time convergence of sliding variables despite parameter uncertainties and unknown load torque. The high order sliding mode method is implemented in this paper in order to limit the chattering phenomenon which is the major drawbacks of the standard (first order) sliding mode control. The proposed technique has the property to be simple to implement. Stability of the closed loop, including the observer and the control law, is proved using the separation principal. Simulation results are given to show the advantages of the proposed method.