基于PLC和WinCC的循环冷却水处理智能监控系统

An intelligent supervisory system designed for circulating cooling water based on PLC and WinCC

介绍了西门子S7-200系列PLC和WinCC组态软件应用于工业循环水水质在线监测与自动加药的系统设计与实现技术。针对加酸中pH值过程具有非线性、时变和大时滞等特点,采用了以控制人员的经验为基础的模糊控制方法,结果表明pH值控制误差完全满足系统要求。该系统已在某化肥厂中投入运行,实践证明,控制系统人机交互性好、抗干扰能力强,满足了现代工业循环水质监管的要求。

This paper presents the application of the SIEMENS S7-200 series PLC and the WinCC configuration software to an online monitoring system designed for industrial circulation water quality and automatic adding reagents as well as its implementation. In the process of adding acid, the pH value finds itself often in nonlinearity, time change, long lag, etc, thus adopting a fuzzy control method based on opera- tor＇ s experince. The result indicates the pH control error can satisfy the technological requirement. This system has been put into operation in a chemical fertilizer plant. Its application shows that the man-ma- chine interaction is good and the ant-jamming function is strong. The system can meet the requirement for mornitoring the quality of modern industrial circulation water.