In order to improve the efficiency of the compressed air energy storage(CAES)system

a novel CAES system with variable pressure ratio is proposed. The system is realized by adjusting valves to change the series and parallel operation modes of compressor stages

which is based on the characteristics of constant volume gas storage devices and traditional compression with constant pressure ratio. The time for energy storage

the power consumption of compressor and the charging and discharging efficiency of system are calculated by analyzing the feasible operation modes of variable pressure ratio under different compression stages and establishing the simulation models of the variable pressure ratio CAES systems

which are compared with the parameters of conventional CAES system with constant pressure ratio. The results show that the new system can not only reduce the power consumption of the compressor group in the energy storage process and shorten the energy storage time

but also improve the charging and discharging efficiency of system compared with the conventional CAES system with constant pressure ratio.