The Research On Modeling And Decoupling Strategy Of Circulating Fluidized Bed Boiler

Recently, environmental pollution is serious than before. The circulating fluidizedbed boiler has attracted the attention of many scholars at home and abroad with its lowpollution and high efficiency combustion technology. However, it is difficult to set up themathematical model of circulating fluidized boiler. Therefore, this paper gets rid oftraditional method of modeling, it establishes fuzzy model of circulating fluidized bedboiler. Finally, this paper designs two decoupling controllers basing on fuzzy modeling.Accurate and effective mathematical model is the basis for getting good control result.In this paper, it establishes fuzzy models for bed temperature and the main steam pressureof the circulating fluidized boiler by using the experimental data between inputs andoutputs. This fuzzy model is more suitable for describing the input-output relationship ofthe system than the traditional transfer function model. Fuzzy neural network algorithm isused to establish the fuzzy model. This method combines the reasoning ability of fuzzylogic with neural network learning ability and has clear physical meaning. The fuzzymodel of bed temperature and the main steam pressure contain five fuzzy rules separately.Circulating fluidized bed boiler is a complex controlled object. There exists seriouscoupling between the bed temperature and the main steam pressure in the practicalproduction. In this paper, it designs PID neural network decoupling controller and fuzzyneural network decoupling controller according to fuzzy model character. The simulationresults before and after decoupling shows that both of these two controllers all can achievethe control requirements but the system with fuzzy neural network decoupling algorithmhas more advantage in system responds speed and it can realize the decoupling in fewersteps compared with PID neural network decoupling.