Design and Application of Control Strategy for the "Single Forced Draft Fan, Double Induced Draft Fan, and Double Air Preheater" Configuration of Air and Flue Gas System in Thermal Power Units

A sequential start control scheme for the air and flue gas system was designed for the configuration of " Single Forced Draft Fan, Double Induced Draft Fan, and Double Air Preheater ", which improved the control level of the entire air and flue gas system; Based on the configuration characteristics of the air and flue gas system, a targeted control scheme for induced draft fan RB and air preheater RB has been designed to ensure rapid and stable load reduction of the unit after a single side auxiliary machine failure; Protection and control logic of the fan was designed, which can ensure the safety and reliability of the air and flue gas system. The complete control strategy for the air and flue gas system proposed in this article has been applied in ultra supercritical 660MW thermal power units. It has been verified to have good applicability for the air and flue gas system with a configuration of "Single Forced Draft Fan, Double Induced Draft Fan, and Double Air Preheater". The entire system has good automation control level and safety reliability.