Feasibility Study And Economic Analysis Of Coupling Micro Pumped Storage And Lithium Battery Multi Energy System

With the rapid development of the world’s energy sector,increasingly serious environmental pollution and increasing energy demand have become urgent challenges to overcome.The microgrid energy storage system includes distributed power sources,energy storage devices,and loads,which can achieve self-sufficiency in local areas,improve the utilization rate of renewable energy,and achieve sustainable development.This article uses the NASG-II algorithm to optimize the configuration of microgrid energy storage systems with system economy,power supply reliability,and energy loss as objective functions,and analyzes the performance of the optimal configuration microgrid system.The main research content is as follows:(1)Taking into account the distribution of natural resources in remote areas,determine the type of distributed power source.Based on the advantages of high energy density,good load regulation performance,and high energy storage efficiency of electrochemical energy storage;Due to the advantages of mature technology,low unit energy cost,and long service life of micro pumped storage devices,lithium battery packs and micro pumped storage devices are chosen as energy storage devices.On this basis,a microgrid energy storage system is constructed,and based on existing research,energy storage devices and distributed power mathematical models are established to develop different types of microgrid system operation strategies.(2)Considering factors such as the economy,power supply reliability,and energy loss of the microgrid system,the NASG-II algorithm is adopted,with photovoltaic power generation capacity,wind turbine power generation capacity,lithium battery pack capacity,and micro pumped storage capacity as decision variables to constrain the charging and discharging power of distributed power sources,energy storage device power,and system operating power.The evaluation indicators are load loss expectations/purchased electricity from the grid,unit energy cost,and supply demand ratio,Optimize the configuration of all schemes for the microgrid system.(3)Off grid microgrid systems include four different types of microgrid systems,namely photovoltaic cells,photovoltaic pumped storage,photovoltaic wind cells,and photovoltaic wind pumped storage.Simulate the optimal configuration schemes of four systems using HOMER Pro software to obtain corresponding objective functions and system operation data.Analyze the photovoltaic energy storage system and solar wind energy storage system separately from the operational status of system components,optimal configuration scheme,and objective function.In photovoltaic energy storage systems,photovoltaic pumped storage systems are superior in terms of economy and energy loss compared to photovoltaic battery systems,but their power supply reliability is poor.In the solar wind energy storage system,the solar wind pumped storage system is superior to the solar wind battery system in terms of economy,power supply reliability,and energy loss.(4)The grid connected microgrid system,due to its energy interaction with the power grid,proposes a peak valley electricity price mechanism based on this,which can improve the economic efficiency of the microgrid system.When the microgrid system is connected to the grid,it includes solar wind batteries and solar wind pumped storage systems.Based on the analysis of the optimal configuration schemes of the two systems and the operating status of each component,it is found that the peak shaving capacity and energy storage efficiency of lithium battery packs are higher than those of micro pumped storage devices.However,the lifespan of lithium battery packs is shorter and their safety is poor.From a long-term perspective,using micro pumped storage devices is more reasonable.In addition,the impact on the environment needs to be considered when the microgrid is connected to the grid for operation.The results indicate that the solar wind pumped storage system is superior to the solar wind battery system in terms of economy,energy loss,and environment.