| In recent years,the penetration rate of distributed generation in electric energy is increasing.Distributed power generation is random and unpredictable,which will bring power shortage between the load and the power generation end of the islanded operation mode,which will affect the reliable operation of the microgrid.The scientific and rational capacity allocation of energy storage system can reduce the load shortage rate,improve the new energy consumption rate,and ensure the reliable operation of the microgrid.Therefore,it is of practical significance to study the capacity allocation of the energy storage device in the microgrid.This paper studies the capacity configuration of hybrid energy storage system in the wind and light microgrid under the islanded operation mode.The main work contents are as follows:Firstly,the research status and application of energy storage technology in microgrid are analyzed.The data analysis,reliability analysis,objective function selection and solution of microgrid hybrid energy storage system capacity allocation are explored.Capacity allocation studies provide theoretical support.Secondly,the wind power storage DC microgrid is taken as the research object,and the power characteristics of photovoltaic power generation and wind power generation are analyzed.By considering the randomness of illumination,wind speed and load,the mathematical probability model at a certain moment is studied and established by time series sampling method.The operation status of each unit in the microgrid in time series is established,and the reliability indicators such as load shortage rate and new energy consumption rate are established.Combined with the second-order low-pass filter and the energy storage and discharge model,a hybrid energy storage control strategy is proposed.The reliability index calculation analysis method.The results of the example show the effectiveness of the reliability analysis method based on hybrid energy storage control strategy in wind and light storage DC microgrid.Thirdly,the Monte Carlo method of Latin hypercube sampling is used to calculate the illumination,wind speed and load history data,and the output range of photovoltaic power generation,wind power generation and load with a confidence interval of 90% is obtained.The acquisition cost of the hybrid energy storage system is proposed.The minimum operating cost is the objective function,and the reliability index is set as the penalty function to establish the economic benefit model for the capacity allocation of hybrid energy storage systems.Fourthly,for the problem that the global convergence difference in simulated annealing directly affects the optimal solution of the model,this paper uses the temperature rise strategy to improve the temperature update function in the algorithm,and uses the memory to collect the optimal solution to enhance the global optimization ability of the algorithm.Combined with the test function,the feasibility of improving the simulated annealing algorithm is verified by comparing the simulation results of particle swarm optimization algorithm and simulated annealing algorithm.The improved simulated annealing algorithm is used to solve the hybrid energy storage capacity configuration model.Taking an islanded-type microgrid as an example,a case study is carried out.The results show that the capacity configuration method and the limit scene capacity configuration method in a typical scenario are mentioned.The rationality of the optimal capacity sizing method is verified. |
PDF Full Text Request