Analysis on modeling and solving for electric power-energybalance in new-type power system

Electric power-energy balance in new-type power system plays a significant role in power source planning, design and selection of power station characteristic parameters, and argumentation of power station demand scale for regulating capacity;however, it still faces many challenges such as increasingly complex operation constraints of power sources, insufficient coverage of modeling constraints, and limited application scope of solution algorithms. To fully utilize the regulating functions of conventional hydropower stations and pumped storage power stations, and to reasonably arrange the working positions of various power sources in the power load diagram, a power-energy balance model that meets the operation requirements of various power sources such as "wind, photovoltaic, hydropower, thermal power, and energy storage" was constructed. Based on the cumulative energy curve method, the working position of conventional hydropower stations in the daily load diagram was determined; the coordinated operation mode of peaking and valley filling for pumped storage and new-type storage energy power stations was studied and proposed, and a set of solution algorithms was developed. An example study was conducted on the Xinjiang power grid. The results showed that the curtailment rate of wind and solar power generation in August and December of Xinjiang power grid in 2035 were 4.34% and 0% respectively, and the thermal capacity on state were 51668MW and 67234MW respectively. The results demonstrated that when wind and solar power were fully integrated into the power system, the peak-valley difference of the power system significantly would increase. Therefore, pumped storage and new-type storage energy power stations needed to play the role of peaking and valley filling load, so as to achieve efficient consumption for clean energy. Through this preliminary analysis of the power-energy balance in Xinjiang power grid, the applicability and effectiveness of the proposed model have been verified, which can provide a reference for the design and operation research of power stations.