An Improved Higher-order SFR Model of Large-scale Distributed Hybrid Power System

In recent years, distributed renewable generation has become vital energy support in large-scale power systems. After the different distributed renewable generation connected to the main grid, the analysis and control of power system become more diverse and complicated. This paper proposes an improved system frequency response (SFR) model to predict the frequency dynamic of large-scale distributed hybrid power system more accurately. This paper firstly expands the constants of mechanical power gain factor within traditional SFR model into a first-order inertia link, which can accurately simulate the mechanical power gain factor. Then there extends the generator damping regarding the damping of generator, excitation system and load effect, which can accurately simulate the damping influence of the system frequency dynamics. Finally, the paper proposes a tuning method of related parameters of higher-order SFR model. The simulation results verify that the higher-order SFR model used to predict the power system frequency dynamic is accurate and effective.