Model predictive control-based load frequency control for power systems with wind-turbine generators

In order to smooth the system frequency disturbances caused by wind power fluctuation, this study proposes a novel load frequency control (LFC) strategy based on model predictive control (MPC) to regulate the system frequency. The proposed strategy mainly aims to improve the system frequency responses by considering the dynamics of wind turbine (WT) and forecasting the output power of WT. First, the frequency response model (FRM) of system including the power system LFC and WT is established. Second, through discretisation of the FRM, a predictive model of system is obtained. Then, system state and response in the next predictive period are forecasted by the predictive model. After obtaining the prediction information, the control signal of system is optimised for improving system frequency response. On this basis, a novel MPC-based LFC strategy is proposed based on the predictive model and the optimisation of control sequence. With the information of wind speed, this control strategy is able to forecast the system states and responses easily and adjust the control signal according to wind power fluctuation. Finally, numerical simulations are demonstrated to visualise the effectiveness and feasibility of the proposed MPC-based LFC strategy and its advantages over existing methods.