Research And Application Of Control System For Circulating Fluidized Bed Boiler Based On F8-DCS

The Circulating Fluidized Bed Boiler (CFBB or CFB Boiler) is a new generation of coal combustion technique developed in the last few decades. For the advantage of broad fuel flexibility, high combustion efficiency, good load-following capability, and low pollution, CFBB has been widely used in all over the world.However, CFBB is a new-type boiler with immature technique till now, it has more input and output variables than the ordinary boiler because of its own characteristics. The combustion process is highly non-linear, time-varying and undue lagging, the coupling relations between variables are very complicated. In the current time, especially, the combustion mechanism is still under research, there is no complete real-time control model can be referred to. Therefore, how to control the combustion process of CFBB effectively is always the focus to the researchers.Firstly, with the actual project—-the DCS of Hai'an Huaxin 75t/h CFBB thermal power plant in Jiangsu province as background, CFBB working principle, development status and control difficulties are introduced in this paper; Secondly, the characters of every subsystem in CFBB are analyzed deeply, taking the advanced control theory into CFBB drum level by a simulation study of fuzzy-PID control, especially for the CFBB bed tempreture, a set of expert control strategies are designed; Lastly,The DCS has been completed and debugged in the field, after function module preparation and hardware /software configuration by domestic F8-DCS system from Beijing LongyuanZhenghe Ltd,with independent intellectual property rights. During five months' trial operation, the system ran well, all the problems of CFBB have been basically solved. The effective functions of this system can also play a positive role to promote the application of domestic DCS.