The Research On300MW Unit Of The Superheated Steam Temperature System Modeling And Control Algorithm

The boiler export lead hot steam temperature is one of the important parameters of boiler,continuously innovating along with science technique development and machine set capacity to continuously enlarge,lead the hot steam temperature controls of inertial time constant and delay time is all very big and express not line in the certain degree and changes along with time.For overcoming these weakness,building up more accurate model to lead hot steam system to seem to be very important.This text made use of the in general use integral whole turns to imitate true system(GISS)-the propped up software Cybersim to once build up dynamic state mathematics model of hot vapor system.This imitate true model according to basic physical laws,make use of window way to turn and mold piece the model method.The method can in on-line or hand over with each other way modify and adjust to try model.And this dynamic state model can imitate each change quantity of complicated relation in bigger scope about lead hot vapor system,truely reflecting system’s variety in time and not line.In the thermal power plant,the control object of the boiler hot steam temperature control system is superheaters.They work under the heat and high pressure condition.The superheated steam temperature of boiler outlet is the maximum temperature in the the steam and water process.The stability of superheated steam temperature is very important on the safety and economic operation of the unit.So for the control of superheated steam temperature is higher.But as a result of superheated steam temperature is a typical large delay, large inertia, nonlinear and time-variable complicated system,using the classical control theory in superheat steam temperature control has some shortcomings.This paper adopts the front guiding differential signal of the double loop control strategy of superheated steam temperature.Because of the differential signaling role in the object equivalent,It makes the equivalent object has a smaller delay and inertia,thus achieving the effective control of superheated steam temperature.