Identification of boiler models

The paper describes the application of system identification techniques to obtain models of boilers in power stations. Initial work involved extensive simulation studies, using a detailed nonlinear boiler model, to evaluate methods of identification and investigate model structures, disturbance levels etc. Three sets of tests were performed in power stations, using a computer-based data-acquisition system. Pseudorandom binary sequence inputs were applied to the plant, the responses were monitored, and these data were processed to derive models of the plant, using a two-stage recursive-least-squares algorithm. Results are presented which compare the responses of the identified models with those of the plant, and show that the models provide an accurate representation of the real system.