Fractional order sliding-mode control based on parameters auto-tuning for velocity control of permanent magnet synchronous motor

A fractional order sliding mode control (FROSMC) scheme based on parameters auto-tuning for the velocity control of permanent magnet synchronous motor (PMSM) is proposed in this paper. The control law of the proposed FROSMC scheme is designed according to Lyapunov stability theorem. Based on the property of transferring energy with adjustable type in FROSMC, this paper analyzes the chattering phenomenon in classic sliding mode control (SMC) is attenuated with FROSMC system. A fuzzy logic inference scheme (FLIS) is utilized to obtain the gain of switching control. Simulations and experiments demonstrate that the proposed FROSMC not only achieve better control performance with smaller chatting than that with integer order sliding mode control, but also is robust to external load disturbance and parameter variations. (C) 2012 ISA. Published by Elsevier Ltd. All rights reserved.