Wind turbine power maximisation based on adaptive sensor fault tolerant sliding mode control

This paper presents a new strategy to robust fault tolerant control (FTC) to optimise the wind energy captured by a wind turbine operating at low wind speeds, using an adaptive gain Sliding Mode Control (SMC). In addition to the inherent robustness of SMC against matched model uncertainty, the proposed method involves a robust descriptor observer design that can provide robust simultaneous estimation of states and the “unknown outputs” (sensor faults and noise) in order to guarantee the robustness of the sliding surface against unknown output effects. Moreover, the sliding surface is designed to achieve the required objectives by utilizing the nonlinear flexible two mass model of the variable speed wind turbine. The proposed FTC SMC method is applied to a 5 MW wind turbine benchmark model.