A Robust Control Strategy of Wind Turbines for Frequency Regulation Support in Power Systems Based on Second-Order Sliding Mode

With the increasing wind power penetration level (WPPL), the frequency regulation support capacity of traditional power systems is insufficient, which seriously affects the safety and stability of system frequency. Aiming at this problem, this paper proposes a robust control strategy of wind turbines based on second-order sliding mode to support the frequency stability of the power system. Firstly, in order to reflect the dynamic behavior of wind turbines participating in frequency regulation support, the wind turbine linearization model is deduced. Secondly, a second-order sliding mode algorithm, namely the super-twisting algorithm, is introduced into the wind turbine frequency regulation support control, and the stability of the proposed strategy is proved by the Lyapunov method. Finally, the effectiveness of the proposed strategy and its advantages are verified by simulation results.