Research On Optimal Scheduling Of Power System Based On Source-Load-Storage Coordination

Nowadays,both at home and abroad pay more attention to the transformation of the supply side structure.China has also begun to accelerate the development of renewable energy.The proportion of renewable energy such as wind power and photovoltaic in the power system continues to grow,and the peak-valley difference of the power grid is also increasing.Due to the intermittent,anti-peaking and uncertainty of wind power and other renewable energy sources,the peak load regulation pressure of the power grid will increase,which will affect the safe and stable operation of the power grid.In addition,at present,the peak regulation of power system also has the problem of high coal consumption of thermal power units.The main factors restricting the peak regulation ability are less flexible regulation resources and unreasonable allocation of peak regulation resources.At present,China ’s coal-fired units still need to further improve their peaking capacity.The proportion of flexible loads in the power system is increasing,and the application of energy storage technology is becoming more and more common.Therefore,how to improve the peaking capacity of power system from three aspects of source,load and storage has become an urgent problem to be solved.To this end,the main research contents and conclusions of this paper are as follows :(1)In this paper,the operating characteristics of different peak-shaving resources in the power grid are analyzed.The peak-shaving,start-stop characteristics of thermal power units in different states and the peak-shaving mechanism of generalized energy storage are analyzed.The common measures for the uncertainty of the output power system are studied to improve the impact of power output and load power errors on the safe and stable operation of the power system.(2)Aiming at the lowest wind curtailment rate and the optimal economy,the optimal scheduling model of power system considering the deep peak regulation initiative and demand response of thermal power units is constructed from the perspectives of source,load and storage.On the power supply side,the model improves the peak regulation ability of the power grid through the peak regulation initiative constraint of the thermal power unit,and increases the capacity of the wind power connected to the power grid.On the load side,economic means are introduced.Through price-based demand response,users can actively participate in power grid regulation to improve the problem of large peak-valley difference of power grid.The energy storage equipment is configured on the side of the thermal power plant to jointly carry out the peak regulation of the power system to increase the peak regulation depth of the coal-fired unit.The example analysis shows that the model can effectively promote wind power consumption,improve the flexibility of system peak regulation and the stability of operation.(3)In order to give full play to the advantages of peak regulation resources in power system,based on the flexibility characteristics of generalized energy storage,a day-ahead and intra-day two-stage rolling optimal scheduling model considering joint peak regulation of generalized energy storage and thermal power units is proposed.The multi-time scale and fast peak shaving characteristics of generalized energy storage are applied in the model.The generalized energy storage and coal-fired units jointly perform peak shaving of the power grid.Through the example analysis,it can be seen that the day-ahead-day rolling optimization scheduling in the model can better deal with the uncertainty problems in different stages,and improve the grid-connected consumption of wind power while reducing the peaking cost.