| Energy storage technology is an effective way to solve the intermittent and unstable problems of renewable energy such as wind power and solar energy,ensure the safe and stable and economic operation of the power system,and help achieve the goal of carbon peak and carbon neutrality.Compared with the more efficient chemical energy storage,compressed air energy storage has the advantages of large capacity and long life.Compared with pumped energy storage,although it has lower efficiency,it has less impact on the environment.In view of the design problem of energy storage system,theoretically,the higher the pressure or temperature of air is compressed,and the heat of compression is fully utilized in the expansion process,the higher the cycle efficiency of the system will be.But in fact,the compressor outlet temperature is limited by the material and the temperature of the heat storage medium.The heat of compression cannot be fully utilized due to factors such as the end difference of the heat exchanger.The conventional design method of equal compression and expansion ratio is because the exhaust temperature is higher than the environment.There is also a large exhaust loss at temperature.Therefore,this paper proposes a method for designing a system without exhaust loss based on the heat storage medium and exhaust temperature to ensure that the system has a high cycle efficiency,while keeping the high-quality compression heat that could not be effectively used in the heat storage tank for further use.This article takes the adiabatic compressed air energy storage system as the research object,and studies the system structure and parameter design methods for reducing loss and improving efficiency for the determined boundary parameters such as the pressure range of the air storage chamber.According to the basic thermodynamic principles,system thermal process technology and the coupling relationship among various components,mathematical models of main components such as compressors,expanders,heat exchangers,heat storage tanks,gas storages,pipelines,etc.are established,and developed based on the Lab VIEW platform The calculation model is designed with equal compression and expansion ratio,and the influence of design parameters on performance is studied.Propose an innovative design scheme for no exhaust loss based on heat storage medium and exhaust temperature,optimize the compression expansion stages and the distribution of pressure ratios at all levels,and develop a calculation model for no exhaust loss design based on the Lab VIEW platform.The influence of design parameters such as heat medium temperature,exhaust temperature,heat exchanger end difference,and inter-stage pressure loss on performance.Compared with the equal compression expansion ratio design,the no exhaust loss design scheme makes the exhaust temperature equal to the ambient temperature,so that the higher-quality compression heat that cannot be effectively used is retained in the heat storage tank.The system heat distribution and utilization at the same heat storage medium temperature The circulation efficiency is better,and it can be designed at any reasonable temperature of the heat storage medium,and the design flexibility is stronger.Research the concept and preliminary design of the compressed air energy storage system,and develop the concept,preliminary design and simulation calculation software based on the Lab VIEW platform.Under the conditions of a given storage chamber volume,working pressure range,unit power generation and time,the design is optimal Structure and parameter system.Two case designs of 100MW/5h compressed air energy storage system were carried out.The temperature of the high-temperature heat storage medium of the system in case one is 420℃,and the pressure range of the air storage chamber is 15MPa～17.8MPa,which can theoretically reach about 67.8% of the electricity.Electricity efficiency: In case 2,the heat storage medium temperature is320℃,and the gas storage pressure range is 8.9MPa～12MPa.Theoretically,it can reach about 63.23% of electricity efficiency;it provides a reference for the design of energy storage system. |
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