Research And Implementation Of OPC Data Access Technology Based On C/S Structure

Along with rapid development of the computer technology and the network technology, hardware and software products are more and more abundant in the field of industrial automation. At the same time, the complex large-scale system integration becomes more difficult. Therefore, whether it is for the user, software developers and hardware manufacturers, it is very necessary to apply a uniform data communication standards.Based on object linking and embedding or component obiect model (OLE/COM) technology, ole for process control (OPC) technology separates the hardware manufacturers and software developers by means of client/server model. They develop’tasks independently. It greatly reduces the systems integration complexity in the process and repetitive work. The technology provided a standard for data communication and access mechanism for the automation system of hardware devices and the client application.This paper focuses on the following aspects:First of all, the core technology of OPC is summarized and researched. It realizes the COM module communication by means of connecting mechanism. OPC standards and OPC system structure are given. A detailed analysis of the OPC three data access mode is listed and implementation of data communications between OPC client and server is given. These flow chart is used for data access in detail.Secondly, windows control center (WinCC) software configuration is designed and used to develop the monitoring system. PLC is used to connect hardware equipment. The third party software PC Access can realize data communication by OPC technology from hardware equipment to monitoring system. The data in the field device is collected and transmitted to the WinCC monitoring system.Then, multiple computers is connected to build a local area network. MATLAB client is developed in the server and client. It finishes interface program and advanced control algorithm by means of MATLAB. The server computer provides OPCserver.WinCC for the OPC server. The multiple MATLAB clients is used to connect WinCC system by OPC technology. The MATLAB powerful data processing capability and functions of WinCC human-computer interation give full play and is made up of WinCC data processing capacity of shortcomings. So it has extended monitoring capabilities of the WinCC for complex systems.Finally, based on OPC technology and communication principle, it develops OPC server by means of Visual C++. The communication can be realized between the VC client and OPCServer.WinCC. Because of the WinCC system in the running process, the computer hardware requirements are higher. The development of two level management system can help user to manage and monitor system better.In order to communicate with multiple objects from standard and universal aspects, the thesis develops the experimental platform based on he theoretical analysis and research of OPC technology.Through the theoretical analysis and research of OPC technology, it can develop the experimental platform from standard and universal aspects. At same time it can communicate with multiple objects. On the use of WinCC development of the control system, the control function and management function have been better expansion.