Power System Multi-machine Frequency Response Model Aggregation of Thermal Power Unit and Hydro Turbine Generator

The frequency response model is the main method to analyze power system frequency dynamic behavior, frequency security and stability control, and optimal control decision. This paper uses the mathematical method to analyze the transfer functions equivalence, which reduces the multi-machine system to an equivalent single-machine model. The equivalent equations of steam turbines and hydro-turbines, and the universal model of steam turbines and hydro-turbines are proposed. The influences of renewable energy sources participating in the power system on system equivalent inertia and the equivalent expression are also analyzed. The IEEE 30-bus system and the typical example system are used to verify the effectiveness and adaptability of the universal model.