Research On125MW Circulation Fluidized Unit About Load Control Methods

As the circulating fluidized bed boiler is a cleanly combustion boiler with high efficiency and low pollution, it has been used widely at home and abroad. This kind of combustion technology has been rapidly developed during these years. Nevertheless, circulating fluidized bed boiler is a complicated control object with large time-delayed, strong coupling, non-linearity and time varying. For the above characters, it’s hard to get ideal control effect with traditional control strategy. This thesis has analysised strategies of load control about125MW thermal power plant in BaoDing. The experimental study is conducted emphatically for the coordinate load control method. It was found that in the "boiler following turbine" mode of operation, the unit has a major fluctuations of coal, which cause the bed’s temperature to sway at too high a rate, also affect the stability of the boiler. However, in the "boiler following turbine" mode of operation, though it has a slower response about the active power, the variation of coal feeding is relatively moderate and the unit has a good stability. As a whole, the "boiler following turbine" scheme is more satisfactory than the former case.