Analysis And Optimization Of Operation Modes Of Advanced Adiabatic Compressed Air Energy Storage System

Global environmental problems such as environmental degradation have made many countries pay more attention to different renewable energy power generation technologies.The proportion of renewable energy power generation in many countries continues to increase,such as wind power generation.However,renewable energy power has great volatility and intermittence,so it cannot produce stable and sustainable power for a long time.When the proportion of power grid connected to it exceeds a certain amount,it may affect the operation of the power grid and the use of users.Therefore,the phenomenon of abandoning electric energy from renewable energy in China is serious.In this case,advanced adiabatic compressed air energy storage(AA-CAES)can make use of renewable energy,and the system can achieve zero emission of pollutants,which is one of the energy storage technologies that can be widely applied in the future.Based on AA-CAES system,the thermodynamic models of advanced adiabatic compressed air energy storage concentrating solar power(AA-CAES+CSP)system and AA-CAES combined cooling and heating power supply(AA-CAES+CCHP)system are established in this paper.The simulation software MATLAB is used.In the third and fourth chapter,the operation modes of AA-CAES+CSP are studied.First of all,based on two kinds of working fluids and two kinds of air chamber modes,four kinds of operation modes are proposed,and the differences of system performance under the four modes are compared.Then,based on the sliding pressure and constant pressure operation mode of the expanders,three operation modes are proposed,and the influence of key environmental parameters and equipment parameter on the system is analyzed.In Chapter 5,the two operation modes of AA-CAES+CCHP system are analyzed and compared,and the sensitivity of three parameters is analyzed.The conclusion is as follows:(1)For AA-CAES+CSP system,for the four operation modes,the system cycle efficiency and energy density are the highest when carbon dioxide and constant temperature air storage chamber are selected,in the parameter research range.With the increase of collector temperature and the decrease of ambient temperature,the cycle efficiency and energy density of the system will increase.The increase of heat exchanger effectiveness will increase the cycle efficiency under the four modes first and then decrease,increase the energy density of the system with constant-wall-temperature air storage chamber,and increase the energy density of the system with constant-temperature air storage chamber first and then decrease.(2)For AA-CAES+CSP system,for the three operation modes,the system performance is the highest when the sliding pressure mode is adopted in the range of parameters studied.The highest efficiency is 72.56%,and the ambient temperature is 253 K.The simulation results show that the increase of ambient pressure will increase the cycle efficiency and decrease the energy density,and the increase of ambient temperature will decrease both the cycle efficiency and the energy density.The reduction of the pressure range of the air storage chamber will improve the cycle efficiency and reduce the energy density,and vice versa.(3)For AA-CAES+CCHP system,the exergy efficiency and exergy density of mode2 are the highest in the range of parameters studied.When the heat exchanger effectiveness reaches 0.925,mode 2 achieves its highest exergy efficiency,68.39%.With the increase of heat exchanger effectiveness,the exergy efficiency of the two modes increases first and then decreases,and the exergy density increases continuously.In the two operation modes,the exergy efficiency and exergy density first decrease and then increase with the increase of convective heat transfer coefficient,and increase with the decrease of energy storage interval time.