电热冷联产的新压缩空气蓄能系统

A New Type of Compressed Air Energy-storage System for the Cogeneration of Electricity, Heat and Cooling Energy

提出一个将压缩空气直接在空气透平中膨胀做功发电,并产出热量和冷量的新压缩空气蓄能方法。分析了该新压缩空气蓄能系统工作的不可逆循环,并建立了仅忽略所有换热器流动阻力损失的该蓄能系统之能量转换利用率(η)计算方程式。用该方程分析研究了空气透平膨胀机与压缩机等熵效率、压缩机排气热能度、空气透平排气冷量度、换热器传热温差和空气压缩比等参数对系统η值的影响,发现空气透平等熵效率提高对η值的贡献大于压缩机效率同样提高的功效;在其它参数确定时,存在最佳压比,可使系统的能量转换利用率在该条件下达极值。分析表明:电热冷联产新压缩空气蓄能系统的能量转换利用率可达0.8左右。

A new type of compressed air energy-storage system is proposed, under which compressed air directly expands in an air turbine to do work and generate electricity, produce heat and cooling energy. The irreversible cycle of the system is analyzed and an equation given for calculating the energy-conversion utilization rate η of the energy storage system when only the flow resistance loss of all heat exchangers is neglected. By using the above-cited equation an analysis and a study are conducted of the influence of the following parameters on the system η value: isentropic efficiency of air turbine expansion machine and compressor, compressor discharged air heat energy, air turbine discharged air cooling energy, heat-transfer temperature difference of heat exchangers, air compression ratio, etc. It has been found that the increase in air turbine isentropic efficiency has a greater influence on η value than that of a same increase in compressor efficiency. With all the other parameters being fixed there exists an optimum pressure ratio, under which the system energy-conversion utilization rate attains a maximum value. The results of the analysis indicate that the compressed air energy-storage system under discussion can achieve an energy conversion rate of about 0.8.