Research Of Industrial Ethernet In Sewage Treatment Automatic Control System Of Cigarette Factory

With the global water crisis is getting more and more serious, water protection is urgent, and it is significant to treat the sewage reasonably and effectively. In this paper, sewage treatment project of a cigarette factory is research object, using industrial Ethernet technology to complete the design and implantation of sewage automatic control system.Firstly, through the introduction and comparison between DCS, fieldbus and industrial Ethernet, we can find the advantage of the industrial Ethernet in industrial process control. Since it has reputation of "one network to the end " which can extend to the industrial field control layer, so the industrial Ethernet is selected to be the communication network, which can complete the information exchange between monitoring management layer and field control layer.Secondly, according to the sewage treatment craft of the cigarette factory, sewage automatic control system is designed. It is composed of the upper and lower computer, Yanhua IPC is selected as monitoring management computer, SIEMENS S7-300 PLC is selected as lower computer to control field, and the communication of two computer is carried by industrial Ethernet. The field control layer is divided into three PLC control stations, the control function and configuration of each PLC control station is introduced in detail, and the configuration screen of monitoring management is designed too.Finally, in view of the complexity of sewage treatment, select the dissolved oxygen (DO) of aeration process as the research object of control algorithm. According to the experiences, the approximate simulation model of aeration process is established, and the fuzzy PID control strategy is proposed. In Matlab simulation experiment, though comparing with PID control, it turns out that fuzzy PID control strategy is effective and enforceable.