| The grid volume is developing fast.The most difference between peak and off-peak demand of power generation is about 40%. Its performance is dependent on energy storage system because of the load fluctuation. Some problems can be solved by electrical energy storage system, for example, the improvement of reliability and steadiness of power supply. Each of energy storage ways has advantages and disadvantages. Compressed air energy storage (CAES) has advantages of low investment, low operation & maintenance cost and large power load range. Acknowledging the support from Natural Science Foundation of Beijing(No. 3053019)& National Natural Science Foundation of Chin(aNo.50476069), thermal performance simulation & benefits analysis of CAES was studied in thesis. Main contents and results of the thesis are as follows.Combined with the characteristic of energy storage subsystem and its components, a subsystem dynamic-state and static-state simulation model is proposed based on unit's modeling system. Equipments selection and their dynamic characteristics are analyzed. Using simulation software, the dynamic-state and static-state thermal performance are simulated for an energy storage subsystem. The simulation diagram of curve is plotted. The conclusion is drawn as follows: with the storage of compressed air, the pressure of storage vessel is varied from 30bar grows to 144bar, the mass flux of compressing air is reduced to 403.7kg/s from 411.2kg/s, the work usage of compressing air is reach to 706kJ/kg from 412.8kJ/kg.Linked with the flow structure and dynamic characteristic of making electricity subsystem and its components, a dynamic-state and static-state simulation model of making electricity subsystem is proposed. Dynamic-state and static-state thermal performance have been simulated with constant air mass flux and constant gas combustion temperature. Some simulation diagrams of curve are plotted also. The contrastion of varied operation mode thermal performance is made between CAES power plant and simple gas turbine power plant. The conclusion is drawn as follows: with the load variation of gas turbine from 100% to 40%, the thermal efficiency of gas turbogenerator is varied from 33.8% to 0, the energy transformation coefficient of CAES power plant is changed from 53.6%~49.5% with constant gas temperature & changed from 53.6%~34.3% with constant mass flux.On the basis of"Energy Step Utilization"principle and laying emphasis on characteristic of CAES power plant, the system integration and optimization method is proposed and the system integration of CAES power plant is made. Thermal performance of different CAES power plants is calculated, contrasted and analyzed and some conclusions are made. On the basis of 7E gas turbine, the power of CAES power plant is 2.39~3.33 times of simple gas turbogeneratior. The energy transformation coefficient of CAES power plant is 38.2%~54.4%.A static and dynamic benefit evaluation model of CAES is established. The overall benefit of 1200MW CAES power plant is about 1.55 billion $ neglecting of electrical price difference.Considering power load fluctuation, operation modes are different of micro-CAES electric-generating based on distributed energy system. The net power is -155.9~152.45kW with different models. A simple and practical economy evaluation method and economy evaluation model is established and related calculations are made. The economy is best of using off-peak electric to compress air and using compressing air to make electric, the cost saving is 19.2% constrasted with buying electric from grid overall.By considering the factors including economy, reliability, environment protection, and CO2 emission, a fuzzy overall evaluation model for different power supply mode is proposed. The related calculation and optimization are made. Linking with re-generation power, the overall performance of micro-CAES is best.
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