Aiming at the influence of a photothermal
power station on the frequency characteristics of the surrounding power grids after accessing a
regional power grid, the patent proposes an online predictionmethod for a
power grid frequency situation considering thermal power, photothermal and demand-side response
joint frequency modulation according to a
governor model of a photothermal generator. The method comprehensively considers the functions of thermal power units, photothermal units and demand-side responses in the
system frequency response (SFR) process, and establishes an aggregation modelfor the
joint frequency modulation of the thermal power units, the photothermal units and the demand-side responses by online collecting operation state data of power grids and equipment information of the units. The aggregation model characterizes the process that the thermal power units, the photothermal units and the demand-side responses participate in
frequency modulation in the form of transfer functions. Compared with an existing method, the method adds the
frequency modulation functions of the photothermal unit
governor and the demand-side responses on the basis of a traditional systemfrequency
response model, can perform online prediction on the
power grid frequency situation, and can improve the prediction capability of the power grids to the
system frequency.