5MW超临界二氧化碳循环发电机组锅炉建模与动态特性分析OA北大核心CSTPCD

Enhancing peak shaving capability of supercritical carbon dioxide(S-CO2)boiler is the key to realize flexible operation of S-CO2 coal-fired power plants.Research on dynamic characteristics of S-CO2 boiler is beneficial to optimize the boiler operation control strategies.A dynamic simulation model of S-CO2 boiler is established by the principles of thermodynamics and heat transfer based on the boiler of a 5 MW S-CO2 cycle power unit designed and built by Xi'an Thermal Power Research Institute,and the reliability of the model is validated with operational data from unit.Based on the simulation model,dynamic characteristics of the above S-CO2 boiler under step disturbance of different boundary conditions,such as fuel flow rate,working fluid flow rate,and working fluid temperature,are analyzed.The results show that,the S-CO2 boiler has large thermal inertia,stability times of working fluid temperature at the boiler outlet are different under disturbance of different boundary conditions.With the increase of disturbance range of boundary conditions,stability times become longer.With the increase of boiler heat load,the working fluid pressure at the S-CO2 boiler outlet decreases,and the working fluid flow rate at the S-CO2 boiler outlet increases instantaneously in the initial stages of a dynamic process.