Study On The Bed Temperature Control System Of The Circulating Fluidized Bed Boiler

Bed temperature and mainstream pressure are important index of circulating fluidized bed boiler (CFBB) combustion control system. By the idea of mechanism and imitated modeling, mathematical model describing the bed temperature and mainstream pressure control system of 450t/h CFBB is proposed in this thesis. And some data of the need in the course of modeling are calculated. Dynamic characteristic is simulated on the bed temperature and the mainstream pressure of CFBB under the feed coal flow and airflow disturbing. The mathematic expressions on the bed temperature and the mainstream pressure are identificated. For atuocontrol of CFBB become well, decoupling is studied on the bed temperature-mainstream pressure system in this thesis. The fuzzy feed forward decoupling fuzzy self-turning PID control scheme is proposed and used in the imitation of bed temperature and mainstream pressure control. The simulation shows that the result is satisfactory, and this means cashes relative decoupling. And this system has nicer inner-harass and self-turning decoupling character.