Stability Analysis of a Class of Fractional-Order Nonlinear Systems Under Unknown Stochastic Disturbance and Actuator Saturation

This brief investigates the problem of mean-square exponential stability for a class of fractional-order nonlinear systems (FNSs) subject to unknown stochastic disturbance and actuator saturation. By means of theory of stochastic system and fractional calculus theory, and Cauchy-Schwartz inequality, mean-square exponential stability criteria are obtained. The constraint on the order of the system is relaxed. Meantime, the relevant state feedback controller is designed to overcome the influence of the stochastic disturbance and actuator saturation. Finally, effectiveness of the results is demonstrated via the fractional-order brushless DC motor(BLDCM) system.