Abstract:A scheme of designing fractional order sliding mode controller based on fuzzy inference algorithm was proposed for dealing with the chattering existing in conventional integral order sliding mode controller.Fractional calculus was introduced to design the control law of sliding mode controller.The softswitching will not act on the integral order derivative of sliding mode surface but on its fractional order derivative.Based on the property of fractional calculus,this action will decrease chattering.Moreover,in order to deal with the upper bound of uncertainties,fuzzy logic inference algorithm was used to obtain the gain of softswitching.Simulation results demonstrate that the proposed fractional order sliding mode controller based on fuzzy logic inference system not only can achieve better control performance than the conventional integral sliding mode control system,but also is robust with regard to system parameter variations.