Fuzzy-Sliding-Mode Strategy for Multi-Channel Nonlinear Delay System With Disturbance

In this paper, the robust control of multi-channel nonlinear delay system is discussed. Firstly, a four-order dynamical model of wind turbine nonlinear system suffers from time-varying delay and match disturbances is established. Then, a channel-dependent fuzzy sliding-mode function is designed and the sliding dynamic is obtained. Meanwhile, the stability analysis of sliding dynamic is proved and the channel-dependent sliding parameters are solved. Furthermore, a fuzzy sliding mode controller is proposed to ensure the sliding surface is reachable. Additionally, an adaptive fuzzy sliding mode controller is presented to deal with the situation that the upper bound of the disturbance is unknown. Finally, a numerical simulation and a semi physical simulation are implemented to demonstrate the effectiveness of the algorithm.
Note to Practitioners
—This paper was motivated by the issue of the robust control of multi-channel wind turbine nonlinear system. Different from traditional controlled system, the wind turbine nonlinear system often suffers from the delay and disturbances. This paper designs a new fuzzy-sliding-mode strategy to address the above issues. Firstly, we established a four-order nonlinear dynamic of wind turbine system under the time-varying delay and match disturbances. In order to obtain the sliding dynamic, a channel-dependent fuzzy sliding-mode function is presented. For ensuring the sliding surface is reachable, a fuzzy sliding mode controller is proposed. In order to handle the upper bound of the disturbance is unknown, an adaptive fuzzy sliding mode controller is presented. Both simulation and experiment indicate that proposed approaches are feasible and effective.