Study On Characteristics Of Combined Cooling,heating And Power System Based On Compressed Air Energy Storage Regulation

Under the carbon peak and carbon neutral energy development pattern,CCHP technology has been widely concerned because of its comprehensive utilization characteristics of energy,effectively improve the utilization rate of primary energy,and achieve the effect of energy conservation and emission reduction.However,because the user’s load demand changes with time,the traditional combined cooling,heating and electricity power supply system will operate under off-design conditions for most of the time,resulting in a decrease in the energy utilization efficiency of the system.The integration of the energy storage system with the CHD system will effectively reduce the off-design operating time of the prime mover of the CHD system and improve the performance of the CHD system.Therefore,this thesis proposes a new type of combined cold,heat and electricity power supply system based on compressed air energy storage（CAES）regulation and integrated heat storage device,establishes the thermodynamic model of the system,carries on the thermodynamic performance analysis,and finally carries on the configuration optimization of the system.Based on the law of thermodynamics and the principle of cascade utilization of energy,the traditional cold,heat and electricity triple power supply system is integrated with compressed air energy storage and heat storage system,and a new cold,heat and electricity triple power supply system based on compressed air energy storage regulation is proposed.The work flow of the system is described,and the thermodynamic model of the new integrated system is established.The thermodynamic model includes gas turbine prime mover,lithium bromide absorption chiller,compressed air energy storage system,heat storage system,heat exchanger and other sub-components of the system,in which the fuel of the system gas turbine prime mover is natural gas.Under the given charge and discharge conditions,the thermodynamic performance of the new CCHP integrated system is analyzed.The results show that the output of the integrated system is 1452194 kJ,243004.6 kJ and 566670 kJ respectively,and the power conversion efficiency,primary energy efficiency,primary energy efficiency and primary energy saving rate of the caes system are 57.41%,28.19%,88.06% and 26.61% respectively Sensitivity analysis is carried out for three parameters that affect the system performance: the pressure at the turbine inlet and the flue gas mass flow at the heated turbine inlet.In order to compare the performance of the new system with that of the traditional system,the cooling,heating and power load distribution data of an office building in Guangzhou in summer are used to analyze the operation performance of the above two under this load distribution.It is concluded that the efficiency,primary energy rate and primary energy saving rate of the new CCHP system are 7.58%,10.97% and 18.15% higher than those of the traditional system respectively.This thesis applies NSGA-Ⅱ algorithm,taking daily cost and daily carbon dioxide emission as objective function,to carry out configuration optimization of a new type of combined cold,heat and electricity power supply system integrating compressed air energy storage and heat storage system.The Pareto frontier diagram was optimized,and the optimal Pareto solution was selected to obtain the capacity optimal configuration of the new integrated system.The charging and discharging of the compressed air energy storage subsystem,and the hourly working conditions of flue gas,heat conduction oil and electric refrigerator in the refrigeration subsystem were analyzed.