Study On The Control Of Circulating Fluidized Bed Boiler Combustion And Emulation

Energy is the foundation of the national economy, The development of a nation can not be separated from power. At present, power is mainly generated from coal-fired, When coal-fired is burning in the pulverized coal , the release of SO2, NOX will result in serious pollution of the natural environment. As a new environment-friendly boiler- fluidized-bed boilers, it attracts more and more people's attention, Its development tend to grow in size. However, automatic control of fluidized bed boiler combustion is a major problem. Some people call the boilers as "a week furnace", the mean is that the boiler need stopping and repairing each week. Therefore, to find a good method of control has been a hot issue of study. Against this background, the article studies as following:1. We analysize the mechanism of fluidized bed boiler combustion, and focus on combustion dynamic characteristics of the main steam pressure and bed temperature; as well as the coupling characteristics.of the bed temperature and the main steam pressure2. Combines fluidized-bed boiler of the study of combustion characteristics, we design the"coal– air"and dually limit combustion system which is of collecting the percentage of amount of Oxygen.3. We use the IMC method that is of good robust and anti-jamming capability to control the temperature of bed and main steam pressure which are large inertia and large lag objects; we use the method of approximation to deal with the large lag. By simulating, we find all-Pole approximation effect is better; use PID controller to realize internal model controller; we use GA to set the parameters of IMC, and thoroughly realize use method of IMC to control large inertia and large lag objects.4. We use cascade fuzzy control system which uses all-pole approximation to deal with the lag to realize decoupling of bed temperature and main stream pressure. Based on IMC principle, we design the decoupling system of bed temperature and main stream pressure. The simulation results show the method is effective.