Self-decreasing order multi-loop centralized predictive control system for reheat steam temperature of double reheat unit

Abstract

Disclosed is a self-order-reducing multi-loop centralized prediction control system for a reheat steam temperature of a double reheat unit. The control system is composed of a flue gas recirculation fan rotation speed control loop and a flue gas damper plate opening control loop. The deviations between a single reheat steam temperature and a set value and between a double reheat steam temperature and a set value are sent to a prediction controller to obtain optimal values for a flue gas recirculation fan rotation speed and a flue gas damper plate opening by means of calculation, so as to ensure that the single reheat steam temperature and the double reheat steam temperature of a unit are kept in a rational and safe range. In the present invention, by using prediction control, the problem of the optimization of a great-inertia multi-variable system can be conveniently solved, and a calculation process is clear and simple; during engineering application, programming is convenient to implement, and by means of the prediction of a future output deviation, a corresponding control quantity can be adjusted in a timely manner; and a single reheat steam temperature and a double reheat steam temperature can be stabilized in a rational range, so that the stability and safety of a unit are ensured, and the control effect is better than that of traditional PID control.

Description

technical field [0001] The invention relates to a self-decreasing order multi-loop centralized predictive control system for reheating steam temperature of a double reheating unit, which belongs to the field of thermal power engineering and automatic control. Background technique [0002] With the further improvement of the economic requirements of thermal power units, the units continue to develop to higher parameters, and adopt the double reheating technology to further improve the efficiency of the units. At the same time, the complexity of the unit is further increased, the inertia of the controlled object is increased, and the requirements for the control of the reheated steam temperature are higher. The reheat steam temperature of the double reheat unit is generally controlled by adjusting the speed of the flue gas recirculation fan and the opening of the flue gas baffle, and the adjustment of desuperheating water is generally used for accidental water spraying. The c...

AI Technical Summary

Problems solved by technology

If the traditional PID control is used, the ideal effect cannot be achieved, which requires us to explore other control schemes

Images