Abstract: In order to improve the reliability of microgrid operation and renewable energy power absorbability，

a capacity optimization allocation method of energy storage system based on improved nondominated sorting

genetic algorithm Ⅲ（ NSGA-Ⅲ ）was proposed. Firstly ，a two-layer optimization model of energy storage

configuration was established based on the structural analysis of wind-photovoltaic-energy storage microgrid. The

top layer considers the investment cost of the energy storage system，and the bottom layer considers the actual

operation of the microgrid after the energy storage system is connected. Secondly，the affinity propagation was used to analyze the renewable energy output and load data，and the net load standard deviation index was introduced to realize the extraction of typical daily data. Then，an improved NSGA-Ⅲ algorithm based on differential evolutionary selection strategy was proposed for the proposed multi-objective optimization model. Finally，simulation analysis was performed with typical daily extraction data，and the results verify the effectiveness of the proposed model and algorithm.

      Key words: microgrid；energy storage system；affinity propagation（AP）；nondominated sorting genetic

algorithm Ⅲ（NSGA-Ⅲ）；optimization allocation