Research On Control Strategy Of Reheat Steam Temperature Optimization System In Thermal Power Plant

The reheat steam temperature control system is an important part of temperature control system of thermal power plant, and it is the important basis for safety operation and economic production of the unit. Especially when high capacity units always participate in electricity network load adjustment, reheat temperature control system is required to have a better performance level. Thermal power unit units of our country are controlled by Distributed Control System(DCS), which is characterized by open architecture, and the advanced intelligent control algorithm is applied to the optimization control of thermal power plant. As the reheat steam temperature system is a typical difficult control system with large delay, large inertia and uncertain mathematical model, the traditional PID control method is prone to "over temperature" or "less temperature" phenomenon. Therefore, it is of great significance to use advanced hardware equipment of DCS and to utilize advanced control method to meet production requirements.In this paper, an external optimization station for reheat steam temperature control system is designed based on open structural characteristics of DCS. Two computer simulation experiments are employed to verify feasibility of the system. Information transmission and online controlling of two computers via Modbus/TCP protocol. The fuzzy self-tuning PID control and dynamic matrix control are applied to the optimization control system of external optimization station. The simulation results show that the optimal control system is reasonable and feasible, and the control effect is good.