Research On Capacity Demand Of The Energy Storage In Power System Peak Shaving

With the increase of the scale of new energy generation,the peak and valley difference of the power system is increasing,and the peak shaving ability of the conventional unit is difficult to meet the peak demand of the system.Therefore,the study of coping with peak shaving is of great significance for safe and stable operation in power generation system with new energy generation.In this subject,two methods to evaluate the capacity demand of the energy storage assisting conventional unit in peak shaving are studied,and the method and means are provided to solve the peak shaving problem of the grid new energy generation.1.A practical strategy to formulate technical and economic peak shaving scheme with energy storage and conventional unit is presented.Firstly,a technical evaluation model and an economic evaluation model for the capacity demand of the energy storage assisted conventional unit in peak shaving are established.Next,the technical evaluation index and economic evaluation index are calculated.Finally,a comprehensive technical and economic peak-shaving scheme with energy storage and conventional unit is analyzed.The feasibility and practicability of the practical strategy are verified by two examples of the regional power system and the national system of multi permeability scenarios.2.Optimization model method is used.At first,the optimal model of energy storage capacity is established,including onstraints such as the probability and quantity of lack of peak-shaving,the probability and quantity of wind power curtailment,and the objective function is the minimum cost of peak shaving,Then,the model is linearized and solved by CPLEX solver in the YALMIP toolbox.Two simulation schemes containing energy storage and no-storage energy are set up and the technical and economic indexes of the two simulation schemes are compared and analyzed.The results of two examples show that energy storage can effectively reduce the occurrence of wind power curtailment and lack of peak shaving,and improve the efficiency of new energy utilization and the reliability of system operation.