Optimal Configuration Method Of User-side Energy Storage Based On Two-layer Decision Model

The source of this subject is a sub-project of Shanxi Coal Transportation and Marketing Group Co.,Ltd.’s school-enterprise cooperation project "Design and Energy Saving Analysis of Coal Mine Substation Monitoring System Based on Demand Side Management Platform".With the continuous development of social economy and the improvement of residents’ living standards,the load of various users in the power system will appear to be too different during peak and low periods,which may lead to an imbalance of supply and demand in the power system.It will also increase its electricity costs.However,only relying on increased capital investment to increase annual power generation and expand transmission and transformation lines is not only high in cost,but also low in equipment utilization.With the development of energy storage technology,the method of using energy storage systems to cut peaks and fill valleys has gradually become popular.However,due to the high cost of the energy storage system itself,the analysis of its economic aspects is a research issue that cannot be ignored.Therefore,this paper aims at the penalty problem of large industrial users after exceeding the maximum demand under the condition of electricity demand price,and proposes an optimal configuration model of the user-side energy storage system based on two-layer decision-making.The main research contents are as follows:(1)Establish the overall structure of the energy storage system,including monitoring and control systems,battery units and photovoltaic units,and analyze the necessity of installing the energy storage system.The first part is the monitoring and control system: the design of the overall structure of the wireless monitoring and control system is proposed.Explains the design and implementation of the system.This part includes hardware design and implementation,software design and implementation,and host computer driver design and implementation.The design and implementation of the host computer monitoring and control software in the monitoring and control system are completed.The second part is the battery unit: It describes the use of lead storage batteries,lithium-ion batteries and flow batteries,and analyzes the respective technical characteristics of several batteries.The third part is the photovoltaic unit: the principle of photovoltaic power generation is explained,and the power model of photovoltaic power generation is established.(2)The two-tier decision model is used as the overall framework for energy storage configuration optimization,and the constraints and objective functions of the inner and outer layers are established respectively.Establish a mathematical model for large-capacity energy storage batteries,including cost and output models,as the basis for the overall optimization model.Under the condition of adopting the maximum demand billing of the two-part electricity price,the objective function of the outer layer of the model is the total cost of the energy storage system during the life cycle of the energy storage medium,taking into account the cost of electricity price,energy storage battery and related equipment costs,etc.Factors,the configuration results of energy storage capacity and maximum demand are obtained;the objective function of the inner layer is the cost of the user’s daily dispatching power,and the optimal daily composite load curve is obtained.(3)The outer algorithm in three two-level decision-making is selected for analysis and comparison.First of all,the principle analysis and explanation of the sparrow search algorithm,genetic algorithm and quantum genetic algorithm are carried out;secondly,the respective performance of the three algorithms is tested through two typical test functions,and it can be seen that the convergence speed and ultimate optimization ability of different algorithms have There is a certain difference.It is found that in the test of the two functions,the optimization ability of the sparrow algorithm is more prominent,which verifies the effectiveness of the sparrow algorithm.Therefore,the sparrow search algorithm with faster convergence speed,simpler structure,high precision and novel mode is selected as the outer optimization algorithm.(4)On the basis of the previous two parts,the capacity optimization configuration is carried out.Using the load data of a large industrial user as a calculation example,the calculation example was simulated and optimized with the established double-layer optimization configuration model,and the energy storage configuration results in the two modes of lithium-ion battery and lead-acid battery were obtained,and the results were analyzed.The characteristics and pros and cons of the two batteries are compared with the capacity configuration and economic efficiency of lithium batteries and lead-acid batteries,and the validity of the model is verified.