压缩空气储能系统动态运行特性

Dynamic characteristics of compressed air energy storage system

发展基于可再生能源为主体的新型电力系统,支撑“碳达峰、碳中和”战略目标的实现,由于风、光等可再生能源的间歇性、波动性、周期性等特点,需要集成大规模长时储能系统,提升风光等可再生能源发电的品质与可控性,压缩空气储能具有效率高、成本低、环境友好等优点,被认为是最具发展潜力的大规模长时储能技术。压缩空气储能系统通常为定容储气,因此其储能(储气)过程与释能(释气)过程处于动态,本工作围绕储/释能过程的压力变化,开展了压缩空气储能系统不同运行模式特性研究,建立了部件的动态模型,通过仿真获得了系统主要部件的工作特性,以及系统的总体性能。研究结果表明,在释能过程采取定压和滑压结合模式和扩大储气室压力变化范围可以提高TS-CAES系统效率和能量密度。释能时间为6 h,系统效率和能量密度分别为73.98%、26.49MJ/m^(3)。

Renewable energy is aimed to be the main part of a new electrical system to support the strategic goal of“Carbon Peak,Carbon Neutrality”;however,due to the drawbacks of intermittence,fluctuation,and periodicity of renewable energy,large-scale,long-duration energy storage systems urgently need to improve the quality and flexibility of renewable energy.Compressed air energy storage(CAES)is considered one of the most promising large-scale long-duration energy storage technologies with high efficiency,low cost,and environment-friendly merits.Generally,the CAES system utilizes constant-volume storage caverns.Thus,the charging and discharging processes are under dynamic conditions,especially the storage pressure.Various CAES operation modes,including dynamic component features,are investigated due to the dynamic pressure conditions and system modeling.Similarly,the operation characteristics and performance of both component-level and system-level are analyzed.The results show that the combination of constant pressure and sliding pressure mode in the discharging process,and enlarging the pressure range of the air chamber,can improve the round-trip efficiency and energy density of the TS-CAES system,which are 73.98%and 26.49 MJ/m^(3),respectively,at the discharging time of 6 hours.