Research Of The Networked Fuzzy Control Platform For The Liquid Level System Based On The OPC Technology

With the modern industrial process control systems becoming larger and more complicated,performance requirements to the control system are becoming stricter.One the one hand,openness and inheritable development to the system are strongly needed because of the more and more hardware using in the industry.On the other hand,the more complicated systems need a control algorithm that does not depend on the exact model of the system.In allusion to this matter,the author designs a net fuzzy control system based-on the OPC technology.In this paper,the development and application of OPC(OLE For Process Control)and fuzzy control technology are introduced,with a detailed exploration on its pragmatic significance.The author also explains in detail the working principal and design process of the fuzzy control and fuzzy self-tuning PID control and compares their respective control performances based on the three-tank water level system of Googlo Technology Co.,Ltd.as the object to be controlled.Being a typical multivariable and nonlinear system,the three-tank water level system of Googlo Technology Co.,Ltd.can be utilized to simulate most of the industrial process.Thus the analysis of the control results by the three methods can provide reliable experiences to apply these methods into industrial fields.Then,the kernel and technical specifications of OPC technology are introduced strongly,the method to construct liquid level control system multistage network control platform based-on OPC technology is explained in detail.This system has three level control networks including the site operator station,the engineer station and the expert station.The site operator station is used as an OPC data server to achieve the data collection through the VB program.The engineer station and the expert station use RSView32 configuration software of Rockwell Company,and share the real-time information between the tertiary networks through OPC technological liquid level system.Accord to the result of this system using in the Three-tank Water Level control system,verified the feasibility of network control based-on OPC technology and the effectiveness of fuzzy control and the fuzzy self-tuning PID control algorithm.And because of adopting OPC technology,this platform has higher openness and inheritable development.Other researchers only need to offer the corresponding software OPC interface while developing different control systems and do not need to carry on the tedious communication programming work to the underlying data again.