Frequency modulation technology for power systems incorporating wind power, energy storage, and flexible frequency modulation

The continuous promotion of low-carbon energy has made power electronic power systems a hot research topic at present. To help keep the grid running stable, a primary frequency modulation control model involving multiple types of power electronic power sources is constructed. A frequency response model for power systems is proposed to address the poor accuracy in inertia assessment, and its frequency characteristics are quantitatively analyzed. The results showed that the stable output power of wind turbines was 48.6 MW, the stable output power of energy storage systems was 7.8 MW, and the stable output power of flexible direct current transmission was 18.9 MW. Under the frequency modulation control strategy, as the droop coefficient increased, the steady-state frequency deviation increased by 0.46%, and the safety margin of steady-state frequency deviation increased by 12%. Compared with the separate frequency modulation of thermal power, the maximum frequency deviation of wind power, energy storage, and flexible direct current participating in frequency modulation was increased by 30.36%, and the steady-state frequency was increased by 27.38%. The proposed model can quantify the frequency response characteristics of the power system more accurately, and improve the frequency stability and operation safety under high penetration of renewable energy. It is of great significance to realize the low-carbon and sustainable development of power system.