The novel adaptive sliding mode control for current sensorless synchronous reluctance motor speed drive

This paper presents the a adaptive sliding mode speed control design procedure for robust stabilization and disturbance rejection of the current sensorless synchronous reluctance motor (SynRM) drive system. In this paper, we proposed a novel adaptive sliding mode control to avoid the conventional sliding mode control, which causes high frequency chattering and high gain phenomenon drawbacks due to use the sign function and a larger upper boundary gain to overcome the parameter variations and disturbances of SynRM. This method utilizes Lyapunov function candidate to guarantee the convergence and track the speed command of the SynRM system asymptotically. The estimator of parameter variations and external disturbances is designed to estimate the unknown uncertainty values in real-time. This is different from conventional adaptive sliding mode control to estimate the unknown uncertainty upper boundary. This control scheme doesn’t current sensor and the estimation currents are used in current inner loop. Finally, we employ the experimental results to validate the proposed method.