Research On Hierarchical Wind Power Heating Method Using Air Compression

Wind power generation is the main form of wind energy utilization at present.With the increasing capacity of wind turbines,the problem of excessive weight of generating units becomes more and more intractable.In addition,wind power generation has the characteristics of power fluctuation caused by the fluct uation of wind,which brings about the problem of wind power energy storage and the difficulty of integrating wind power with power grid.In order to solve these problems,the concept of wind power generation based on heat transfer was proposed.Wind energy is directly converted into high-temperature thermal energy as heater sourses for steam generation.Last thermal energy is turnned into electric energy by turbine power generation system.In order to complete the design of wind power generation based on heat transfer,a hierarchical wind power heating system using air compression is proposed in this dissertation.The compressor is directly driven by the wind turbine to compress the air from the environment.High-temperature thermal energy can be supplied to the steam generating chamber.The air is released into the environment after the cycle is over.The hierarchical heating system is divided into two parts: the low-temperature stage and the high-temperature stage.The heat generated by the low-temperature stage is absorbed and utilized by the high-temperature stage.The heating temperature of the system can reach 600 ℃,which greatly improves the quality of thermal energy and enables it to meet the requirements of supercritical steam turbines.According to the principle of hierarchical wind heating system,the layout scheme of the system is put forward,and the thermodynamic model is established.The simulation model of hierarchical wind heating system is established in Aspen Plus.Through sensitivity analysis,the changes of the system COP with the compression ratio,ambient temperature and regenerator are studied.The COP of the system is improved by the optimization and constraint module,and the optimal parameters are obtained.the COP of the system can reach 1.47.This shows that the system scheme is feasible.And the refrigeration coefficient can reach 0.68,which indicates that the system has dual functions of heating and refrigeration.Through the analysis of the second law of thermodynamics of the system,the loss and entropy production of each component are obtained.Finally,the power tracking problem of wind turbines based on heat transfer is studied,and its power control strategy is put forward.The matching characteristic table about wind turbines and compressors is obtained.The wind turbine based on heat transfer combines the hierarchical wind power heating system,high-temperature energy storage and steam turbine power generation.Its efficiency of generating electricity is 70.30%.The aims that the quality control of wind power and decrease the weight of engine room is realized.And the problem of grid integration caused by the natural wind fluctuation is avoided,and the problem of abandonment of wind power is overcome.This paper provides a new way forwind energy utilization.