Fractional order sliding mode controller for the speed control of a permanent magnet synchronous motor

In this paper, a robust Fractional order sliding mode controller (FOSMC) is proposed for the speed control of a permanent magnet synchronous motor (PMSM). The sliding mode controller (SMC), which is insensitive to uncertainties, is studied widely in the application of PMSM drive. Furthermore, it is remarkable to see the increasing number of studies related to the theory and application of fractional order controller (FOC), especially PI^λD^μ controller, in many areas of science and engineering. Research activities are focused on developing new analysis and design methods for fractional order controllers as an extension of classical control theory. In this study, with the exponent reaching law, a fractional order sliding surface is introduced and a FOSMC is designed and applied to a speed control of PMSM, which is typical nonlinear multivariable coupled system. The performance and robustness of the proposed method are tested for nonlinear load torque disturbance, and simulation results show the effectiveness of the proposed algorithm.