Transient Frequency Coordinated Control Strategy for Wind Farm Augmented with Energy Storage

In order to improve the frequency characteristics of the system with wind energy storage after short circuit fault, a coordinated control strategy of wind energy storage is proposed. Firstly, the influence of the wind storage power on the frequency change rate in the frequency rising stage and the frequency extreme value in the frequency recovery stage is analyzed. On this basis, the variable weight coefficient related to the frequency disturbance severity is introduced to establish the optimization model to solve the reference power of the wind storage. Then, the frequency regulation capability of the wind turbine during fault ride through and steady-state operation is evaluated, and the reference power of wind power generation is obtained by considering the rotor energy balance, which is compared with the reference power of wind energy storage to obtain the reference power of energy storage. Finally, the simulation is carried out in the four machine two zone system. The results show that the control strategy can reduce the frequency fluctuation range and accelerate the frequency recovery speed of the wind energy storage network. At the same time, it can make full use of the frequency modulation ability of wind power generation and reduce the impact of speed recovery link.