Frequency Regulation Strategy for Wind Power Considering Grouping Control and Orderly Recovery

Aiming at the power system with high wind power penetration level, a frequency regulation strategy of wind power based on grouping control and staggered recovery is proposed. Firstly, based on the operation characteristics of wind power generators with different control parameters setting of the strategy, wind power generators are divided into groups, which lays a foundation for recovery of subsequent staggered rotor speed and alleviation of secondary frequency impact. When frequency drops, every group of wind power generators raise active power to the maximum value within torque protection limit to restrain frequency drop. Considering that the control strategy based on rotor speed or releasable kinetic energy is decoupled with the system frequency, the reference power of wind power generators is modified by supplementing the frequency overshoot suppression coefficient. The simulation results indicate that by executing staggeringly rotor speed recovery of wind power generators in groups and proceeding the course of regaining back to maximum power point tracking with power adjustment in a "first repress then raise" way, the proposed strategy can smooth the transient process of state switching for frequency regulation and make the speed recovery not too slow. Meanwhile, the frequency overshoot suppression coefficient is introduced to enhance the adaptability of the frequency regulation control for varying degrees of disturbances, which is triggered and decoupled from system frequency. © 2020 Automation of Electric Power Systems Press.