Method Studying Of Integrated Design In Hybrid Energy Storage System With Compressed Air

With the extensive application of renewable energy and the vigorous development of distributed energy supply system,energy storage has increasingly shown a irreplaceable role in improving the quality of energy supply,improving the reliability of the system,improving the energy utilization rate and many other aspects.However,limited by technology,there is not a kind of energy storage that can simultaneously meet multiple indicators such as energy density,power density,service life and cost,so hybrid energy storage technology emerged.In this paper,a scheme of hybrid energy storage system composed of compressed air energy storage,battery and super capacitor is proposed.The problem of capacity allocation and energy management is studied and the integrated design method of hybrid energy storage system with compressed air is proposed.The main research contents are as follows:Firstly,the performance evaluation criteria of hybrid energy storage system including economic and energy saving indexes are given.The flow of various energy in the compressed air energy storage system and the cycle life conversion method of the battery are analyzed.The wavelet analysis and Hilbert-Huang transformation in non-stationary signal analysis are compared,and the ensemble empirical mode decomposition is applied to power distribution as an improvement of Hilbert-Huang transformation.A multiple time scale energy management strategy is proposed.The method aims at economy and energy conservation,optimizes the pre-day output plan for compressed air energy storage which is the pre-day scheduling at long time scale and aims at maintain the energy storage state balance,obtains the energy distribution of each storage device combining with the aforementioned non-stationary signal analysis which is the rolling optimization at short time.Then,based on the analysis of the relationship between the configuration and operation of the energy storage system,a two-stage integrated optimization design method for the hybrid energy storage system with compressed air is proposed.Capacity optimization level optimizes the capacity of energy storage equipment and power generation equipment in micro-grid according to the source-load status combining different evaluations index.The operation level use the designed capacity configuration as input,optimize operation parameters and strategies.After several iterations,the capacity configuration and operation control of the system are optimized simultaneously.Finally,the simulation results of typical examples show that the integrated design can effectively match the configuration and operation of the system and it provides an effective solution for the design problem of energy storage system accessing the new energy micro-grid in the future.