Predictive Control with Disturbance Prediction for SCR Denitration System

Aiming at the characteristics of large delay and large inertia of the SCR denitration system of thermal power units, predictive control technology has been widely used and has shown superior control performance. However, when the system is subject to external disturbances, although the conventional predictive control algorithm has certain robustness, the overall anti-disturbance performance is not ideal. Therefore, for the measurable but uncontrollable external interference signal, we propose a control strategy for the prediction and compensation of disturbance information between coupling loops in this paper. This strategy includes the predictive control increment of the coupling loop through the disturbance prediction value generated by the disturbance model to the current control loop, make full use of the causal information of known disturbances to maximize the impact of uncontrollable inputs on process dynamics. The simulation results show that the control strategy has better interference suppression ability and effectively improves the control effect of SCR ammonia spraying.