两级填充床蓄热器式绝热压缩空气储能系统变工况特性研究

利用压缩机和透平的变工况模型及填充床蓄热器的非稳态模型,对两级填充床蓄热器式绝热压缩空气储能系统一次完整的充放电循环过程进行模拟,分析系统的热力学性能和各个部件的变工况特性。结果表明,系统的充放电效率可达62.4%。储能时,受洞穴内压力变化影响,两级压缩机压比、效率不断改变,从而引起下游填充床蓄热器进口温度变化;释能时,填充床蓄热器出口温度不断降低,引起透平性能变化。

OFF-DESIGN PERFORMANCE ANALYSIS OF A-CAES SYSTEM WITH TWO-STAGE PACKED BED HEAT STORAGE UNIT

Based on the off-design models of compressor and turbine,and the transient model of the packed bed heat storage unit,a complete charge/discharge cycle of the adiabatic compressed air energy storage system with two-stage packed bed heat storage unit is simulated. A detailed thermodynamic analysis of systems overall performance and the off-design performance of main components are carried out. Results show that the system round trip efficiency can reach 62.4%. In the charge process,the compression ratios and isentropic efficiencies of two compressors vary with the increased air cavern pressure,resulting in a variable outlet temperature of packed bed heat storage unit. In the discharge process,the turbines always operate in off-design condition since the decreased outlet temperature of the packed bed heat storage unit.