| The presence and development of fieldbus has brought an involution in industry control field. With its digital, distributed and open character, fieldbus has been a hot issue in control field. The control system based on fieldbus is replacing traditional control system, and represents the orientation of advanced control system.OLE for Process Control (OPC), which is the application of Microsoft's Object Linking and Embedding (OLE) technology in process control system,is the standard interface protocal for connecting the data sources with the client application of the process control. It can greatly inhance the interoperability among control systems, field devices and business applications in the process control industry. In the past, in order to get the data information of the devices from field devices, every application software developer has to write special interface function.Because the variety and unceasing update of the field devices, it brings heavy burden to user and software developer. OPC-based client/server model puts OLE/COM/DCOM mechanism as communication criterion, and it assigns the mission of developing access interface which is provided to user as OPC server to hardware manufacturer or third party. It resolves the contradiction between software developer and hardware manufacturer and realizes the system integration. It can inhance the openness and interoperability of the system.From the development status of the Fieldbus Control System (FCS), this paper introduces the process of standardization in detail, points out the disadvantages of the multi-fieldbus system, which are bad openness, inefficient and poor flexibilty. At last the "paper presents a new scheme of system integration by means of OPC technology.Based on the COM principle, the paper introduces the architecture, object and interface of OPC in detail,and discusses the great benefit whichis brought by OPC to the industry.Furthermore,the paper disserts the implementation principle and applicaton technology of OPC in the practical project,and implements the design and development of OPC interface of SHCAN2000 system.At last it discusses the advanced use of OPC technology in the following three aspects.(1)design and research of advanced control software based on OPC technology and MATLAB toolbox.(2)research of getting field data in client application based on OPC technology(3)the use of OPC technology as middleware.The new SHCAN2000 system after updated has been tested in the laboratory, will be used in actual industry project. The experiment proves that this scheme inhances the performance of system and it is feasible, reliable,universal.The paper makes valueable attempt for OPC standardization of domestic instruments.
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