Coordinated Optimal Frequency Control Method for High-Penetration Renewable Energy Power Grid Based on Multi-Heterogeneous Frequency Regulation Resources

Abstract

: To address declining system inertia, increasingly severe transient frequency stability problems, and the lack of effective coordination among heterogeneous frequency regulation resources with markedly different characteristics—including battery energy storage systems (BESS), wind turbines (WT), photovoltaic (PV) systems, and high-voltage direct current (HVDC) links—in power grids with high renewable energy penetration, this paper proposes a coordinated optimal frequency regulation control method based on model predictive control (MPC). First, the dynamic characteristics of conventional synchronous generators (SG), WTs, PV systems, and BESSs are analyzed and compared in terms of response speed, regulation capacity, and economic characteristics to reveal the complementary mechanisms among these resources. Second, their complementary dynamic characteristics are used to construct a coordinated frequency control optimization model for multiple heterogeneous resources. The model aims to minimize steady-state frequency deviation and total frequency regulation cost, among other objectives, while accounting for system frequency security and the dynamic response constraints of each resource. Finally, MPC is used for receding-horizon optimization: at each control cycle, system dynamics over the future horizon are predicted from measured states, and an optimal sequence of frequency regulation commands is obtained through quadratic programming. The proposed method is tested on a modified IEEE 39-bus system under a 70 MW step disturbance and continuous random load disturbances. The results show that the system frequency recovers to 49.93 Hz under the step disturbance and that the frequency deviation remains within ± 0.011 Hz under random disturbances, demonstrating the method’s combined benefits in frequency security and frequency regulation economy.