Directing against the features

such as the non-linear and uncertainty of superheated steam temperature for the boiler

a PI type fuzzy controller has been used to control the superheated steam temperature of boiler for a 600 MW unit in one power plant

and a PI type fuzzy cascade control system being designed.Based on the analysis of relationship between related parameters of the fuzzy controller and quality of the control system

an on-line selfcorrection method for related parameters has been put forward

constituating a kind of adaptive PI type fuzzy controller.This controller can adjust its quantitative factors and scaling factors on-line

to adapt to dynamic change of the controlled object

thus enhancing the performance of the fuzzy control system.A simulation comparison of the adaptive fuzzy control method with the conventional PID control and the PI control has been carried out

it shows that the superheated steam temperature control system established by using the said method has beeter control quality and stronger adaptive ability.