Regional frequency response analytical model for three-region interconnected power systems considering fast frequency response resources

Frequency Response (FR) is critical for mitigating frequency fluctuations and maintaining stability in power systems, particularly as modern power systems integrate more renewable energy. This paper addresses the challenges of increased frequency variability and decreased FR capabilities. Focusing on three-region interconnected power systems, we examine the limitations of traditional FR analysis methods, comparing simulation and analytical methods, and emphasize the need for Regional Frequency Response (RFR) modeling. We propose a regional active power-frequency model incorporating Fast Frequency Response (FFR) resources, leading to the development of a System Frequency Response (SFR) analytical model capable of resolving FR at the system’s Center of Inertia (COI). This model is further extended to a three-region framework, accounting for transmission line impacts and providing a three-RFR analytical model that offers solutions for FR in any region of the system. Case studies with modified WSCC test system and real-world provincial power system data show that the proposed three-RFR analytical model, with the consideration of FFR resources, effectively captures the Frequency Spatial Distribution Characteristics (FSDC) across regions, enhancing accuracy and efficiency in FR analysis. This work lays a foundation for improved frequency stability in modern power systems.