The Optimization of Hybrid Energy Storage Capacity Considering the Utilization Rate of Tie Lines in Microgrid

The optimization of storage capacity is achieved for hybrid energy storage system with the integration of battery and super capacitor in grid-connected microgrid, and the net load power in microgrid is decomposed by using the discrete wavelet transform to obtain the power distribution of tie lines that meets the requirements of power fluctuation, and to allocate power of battery and super capacitor. Considering the improvement of the utilization ratio of tie lines, the translated adjustment amount of tie-line power is introduced as optimized variable to optimize the hybrid energy storage capacity. The model is built with optimal objective of the economic cost and the utilization ratio of tie lines, and is solved by using of genetic algorithm. It can not only meet the economic requirements, but also effectively improve the utilization ratio of tie lines. In the end, the verification and analysis are carried out through case study.