关键词: 火电机组, 后备软手操, 研究, 实施

Abstract: Distributed control systems(DCS) are implemented in domestic thermal power plants to realize real-time control over the generation units. The main equipments may become inoperational due to DCS failures or improper isolation of on-line maintenance. In this case, generally it is not easy to handle the consequential problems and the accident usually will propagate, causing more severe damages to the power generating units. If there are two different independent control logics in the operation of main auxiliary equipments, of which one is the main control logic in operation and the other is the backup one on standby, the reliability of the auxiliary equipments will be no doubt greatly improved. Therefore, through the study and implementation on soft backup technique in the phase Ⅱ expansion project of Tianji Power Plant, the backup operation on six main draught fans is realized. The movable blades of the six main draught fans can be controlled by the analog control system. It can also be switched to the soft backup control mode. These two kinds of control methods are up and running in different controllers simultaneously, thus the reliability of the analog control system is enhanced.

Key words: thermal power generating unit, soft backup technique, research, implementation