Frequency Regulation Control Strategy of DFIG Participating in Power Grid Based on Stochastic Prediction Theory

With the increasing penetration of wind power in power system, the random fluctuation of power and load brings great challenges to the frequency stability of power grid. To solve the above problems, this paper proposes a frequency regulation strategy based on chance constrained stochastic model predictive control. First, the frequency response model of wind power grid-connected system is established by considering the real-time random fluctuation of wind speed and load. Then, the desired objective function is established to minimize the system frequency variation and wind power fluctuation, and the chance constraint is incorporated into the stochastic optimization model. Finally, according to the distribution information of random disturbance or cantelli inequality, and combined with the state feedback control law to solve the stochastic optimization model, the optimal control law at the current moment is obtained. A detailed wind power grid-connected system model is built in MATLAB/Simulink for simulation verification. The results show that the proposed strategy can effectively suppress wind power fluctuations and system frequency changes, and improve the frequency stability of power grid. ©2024 Chin.Soc.for Elec.Eng.