Abstract: This paper conducts research on optimal dispatch strategies for power systems incorporating active support control strategies of wind power, aiming to enhance system frequency security and operational economy. First, a system frequency response model is constructed, and frequency security constraints are derived with the core of maximum frequency change rate, minimum frequency point, and quasi-steady-state frequency deviation, laying a theoretical foundation for dispatch strategy design. Then, an optimal unit commitment model integrating frequency security constraints is proposed. With the goal of minimizing system operation costs, linearized frequency security constraints are incorporated into the conventional unit commitment model to address the issues of randomness in wind power output and inadequate consideration of dynamic characteristics in traditional dispatch models. Finally, simulation verification is carried out via Matlab in the IEEE 14-bus and RTS-79 systems. The results show that the proposed strategy can significantly reduce the risk of frequency violations and achieve a coordinated balance between economy and security in the dispatch allocation of thermal power units and wind farms.

Key words: power system, optimal dispatch, frequency response analysis, frequency security constraint