Quantitative Evaluation Method for Wind Turbines Participating in Power System Frequency Regulation

The reduction of power system inertia significantly affects the support ability of system frequency, which weakens the anti-disturbance ability. In this paper, the maximum frequency change rate and the constraint of the system equivalent inertia time constant are considered with large-scale wind turbines access in the power system when the system disturbance occurs. The minimum equivalent inertia required by the system is obtained. Next, the method for calculating the capacity of the wind turbines participating in power system frequency regulation under the constraint of inertia time constant is proposed. When the wind turbines participate in system frequency response, virtual inertia, and droop control are considered. Then, the equivalent inertia time constant supporting index, steady-state frequency supporting index, and transient frequency supporting index are put forward to evaluate the frequency regulation ability of the wind turbines quantitatively. Finally, the IEEE-30 bus system is used to verify the effectiveness and adaptability of the proposed method.