Research Of Energy Storage Technology In Distribution Network Considering The Reliability Of Distributed Generation

With the development of power technology and national economy,distributed generation(DG)began to scale into the field of power generation.However,the application of energy storage technology can effectively solve this problem with the characteristics of random fluctuation and uncertainty.Energy Storage System(ESS)shows stability of performance,high response speed and control flexibility.By controlling the output of the Energy Storage System,it can have good wave slow effect on distributed power output.Adding energy storage device in distributed generation system can effectively improve the efficiency of energy utilization,improve the economy of the system,and promote the application of renewable energy resources.At present,the large-scale application of energy storage technology is restricted by its economic factors,so it is particularly important to study the optimal configuration of ESS in the power system with DG.The paper discusses the distribution network with DG and ESS,by the method of distribution network reliability analysis,the cooperative approach of DG and ESS,and Energy storage capacity optimization of distribution network system with DG.Based on DG output characteristics of wind power,photovoltaic and energy storage,the mathematical model is built.And based on the historical data of wind power and photovoltaic power generation,the output probability density distribution function is obtained,so as to build a distributed power supply and energy storage system mathematical model of coordinated operation.Based on the Gram-Charlier series expansion and the calculation of storage based on different operation state probability values,the Distribution network with DG reliability evaluation method is proposed.Based on the multi-objective methods of the cooperative coevolution of heuristic algorithm,the optimal configuration model of ESS in distribution network system with DG is proposed.The traditional multi-objective algorithm is optimized by introducing pareto theory innovatively.The example shows that DG can reduce power outage time in power distribution system effectively.And the optimal capacity energy storage can improve the reliability of the system.