Development And Application Of Simulation System For High Back Pressure Heating Retrofit Unit Based On Star-90

By the end of 2017,China’s total installed power capacity was 1.777 billion kilowatts,and the installed capacity of thermal power reached 1.1 billion kilowatts.The average utilization hours of power generation equipment in China were less than 4,000 hours.Cogeneration units account for a large proportion in northwest,north,and northeast China,and the scale of new energy installed and connected to power grid is growing rapidly.Due to the weak growth of electricity consumption and the increasing demand for heat,it is difficult to fully meet the requirements of the large-scale development and absorption of new energy resources,and serious problems of wind abandonment and light abandonment occur in some areas.In the development of cogeneration,the contradiction between heat and electricity is prominent,and the development mode of large-scale extraction-condensation cogeneration is limited.High back pressure waste heat heating technology can expand heating capacity by recovering waste heat from exhaust steam.At the same tile,flexible peak shaving of heating units by using heat storage technology has attracted much attention.This dissertation is based on the project of National Science and Technology Support Program "Research on Low Energy Cascade Heating Technology of Steam Turbine of Thermal Power Unit".That is to build a simulation platform for comprehensive performance of high back pressure cascade heating system for demonstration units,which can provide prediction of off-design operation state,analysis of load characteristics and operation guidance for units after high back pressure heating transformation.In this dissertation,the development status of simulation of heating units is described in detail,and the high back pressure cascade heatins technology is discussed.According to the case of thermal power plant in Dalian Development Zone,the dynamic model of unit and equipment is built,The automatic control system and flow network model of this unit are developed,and the couplins dynamic simulation system of unit and heat network for high back pressure heat supply transformation is established by Star-90 simulation software,and its accuracy and stability are verified.The results show that the simulation results of the simulation system are basically consistent with the actual operation data of the unit.and can be used in research and engineering applications.For demonstration units,real-time monitoring and forecasting of off-design operation state of units can be realized by using simulation system.The operation and reaulation characteristics of the whole or part of the units and the operation of the heat network can be simulated to obtain the load characteristics of the power plant under full-load conditions,which can truly reflect the phenomena and dynamic characteristics of unit failure.The simulation system based on the high back pressure heat supply retrofitting unit can provide operation characteristics analysis for the unit after the retrofitting,and train the engineers and operators on the operation and fault treatment of the coseneration unit.