| Intermittency, volatility and non-periodicity are important features of wind energy, which can result in the instability of wind power. With the rapid development of wind power, the phenomenon of wind energy curtailment is becoming more serious. Compressed Air Energy Storage (CAES) is recognized as an accepted approach to deal with the curtailment of wind energy. However, fossil fuels which lead to environmental problem have to be used in traditional CAES system. Meanwhile, rare research focuses on the integration of wind power and CAES technology. Therefore, it is necessary to design and develop new kinds of compressed gas energy storage systems which are green, effective and pollution-free and carry out research on the combination of wind power and compressed gas energy storage system. This work can improve the stability of power grid, increase the utilization of wind turbines, and promote the development of energy storage technology.The work in this thesis is carried out based on theoretical analysis and simulation.Firstly, Advanced Adiabatic Compressed Air Energy Storage (AA-CAES) system is chosen as the main research object in this thesis after the analysis of development of CAES technology. Four different kinds of air storage chambers named as VA model, VT model, PA model and PT model are developed according to the thermodynamic characteristics of air storage chamber in CAES system. After analyzing thermodynamic characteristics of four air storage chamber models, AA-CAES system model is established and the thermodynamic characteristics of AA-CAES system with different air storage chamber models are analyzed and compared. In addition, this paper studies the correlation among system, components and parameters.Secondly, based on thermodynamic analysis and simulation, a hybrid system consisting of wind, wind turbine and AA-CAES system is established through Matlab/Simulink platform. Energy conversion and transfer in hybrid system are analyzed and compared under different wind conditions. The results show that there are several different forms of energy in hybrid system and system efficiency are mainly affected by wind turbine and charging process of AA-CAES system. The proportion of wind energy converted to heat energy is higher at low wind speed while the proportion of wind energy converted to internal energy of air is higher at high wind speed under stable wind speed, and the change trend of proportion of wind energy converted to heat energy is opposite to that of internal energy of air when wind speed changes. Besides, it is found that unstable wind conditions mainly affect energy conversion in wind turbine as well as energy conversion related to thermal energy in AA-CAES system, and it is compressor efficiency that mainly affects energy conversion efficiencies of other components during charging process of AA-CAES system.Thirdly, this paper studies the utilization of AA-CAES technology in the field of distributed energy to develop application potential of AA-CAES technology. A new distributed energy system model which is able to realize different working modes of energy supplying is proposed based on AA-CAES technology in the thesis. Parameters affecting working modes of the system are also determined. In addition, the performance of energy supply and loss in components are analyzed on the basis of energy and exergy analysis. The correlation between system working modes and system parameters, such as turbomachinery efficiency, pressure ratio and effectiveness of heat exchanger, is investigated. The results show that the amount of energy (electricity, heat and cold) supplied and system efficiency are directly related to thermal energy distribution in Thermal Energy Storage. The proportions of exergy loss in components are different under different working modes. Besides, the impacts of variation of parameters on system efficiency are different for different working modes. From the perspective of exergy, the increase of turbomachinery efficiency and effectiveness of heat exchanger can reduce exergy loss and improve the total exergy efficiency of system.Finally, with carbon dioxide as working medium, analysis, design and optimization of new energy storage systems are carried out in this thesis. The thermodynamic model of thermoelectric energy storage system is established and the relationship among system, cycle, components and parameters is investigated in terms of cycle and actual operation. The difference and relevance of thermodynamic characteristics of system in terms of cycle and actual operation are compared, which provides theoretical support for the optimization of thermoelectric energy storage system. In addition, several new energy storage systems using supercritical carbon dioxide as working fluid are proposed on the basis of ranking cycle and brayton cycle. A kind of energy storage system based on ranking cycle is proposed, which can use wind energy and solar energy as energy source. A hybrid system based on ranking cycle and compression refrigeration cycle is developed, which can further improve wind energy utilization and be used in the field of distributed energy. New kinds of energy storage systems based on brayton cycle avoid the use of fossil fuels with the help of thermal energy storage and high system efficiency could be expected. The new kinds of energy storage systems using carbon dioxide as working medium provide new ways to the utilization of renewable energy and development of energy storage technology. |
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