Optimal Configuration of Energy Storage Capacity in Multi-energy System with Temperature Control Equipment Based on Discrete Fourier Transform

The reliability and economy of the system can be effectively improved by allocating the proper capacity of the hybrid energy storage in multi-energy microgrid. In this paper, a Discrete Fourier transform (DFT) of power distribution method is established to measure the response characteristics of electrical and thermal storage. The proposed method ensures that the electrical storage and thermal storage work in their respective appropriate states. After the DFT decomposition, the corresponding electrical storage operation strategy is modeled in the high frequency subsystem, while thermal energy storage in the low frequency subsystem considering temperature control of thermal load. On this basis, a bi-level capacity optimization model with the minimum equivalent annual cost as the objective function is established which can simultaneously determine the allocation of energy storage and their capacity configuration. Case study is given to verify the effectiveness and economy of the proposed method.