Application of Siemens S7-300 PLC In the thermal power plant flue gas desulfurization control system

According to the characteristics of Wet Flue Gas Desulphurization (FGD), this paper brings forward the automatic control requirements and the control methods. The automatic control system is composed of a Programmable Logic Controller (PLC) and an industrial control computer (PC). The automatic control system can monitor the operating parameters of FGD system automatically and conduct automatic control and adjustment to FGD system. The PLC is responsible for the data collection and automatic control, while the PC is responsible for the surveillance of FGD system operation and the data processing through mutual communications between PC and PLC, which realizes the communication between human and machine and ensures the safe, stable and economic operation of the FGD system.