Application Of OPC In Integrated Platform For Advanced Control Software

To improve competency and get advantage in the market, process industry becomes more and more paying attention to the enterprise information construction, which is to enhance the productivity by using advanced control theory and software. However, the existent advanced control software has single function, bad integration and interaction each other. Under this background, this paper studies and designs an integrated data platform for advanced control software based on OPC technology. The core of the platform is real-time database, and its main communication is based on OPC. This platform not only has the function of real-time database, but also provides better support for advanced control software.Firstly, this paper introduces the basic knowledge of advance control software and real-time database. Secondly, it analyses detailedly the necessary and function of the platform. And then it presents an integrated architecture of the platform, analyzing the virtue of structure at the same time.The emphasis of this paper is to realize OPC data interface for the platform, including OPC data server and OPC client programs. On the basis of studying deeply OPC DA specification, this paper presents the method and process of OPC server development in the terms of data structure of OPC server, OPC address browse space, registering server and data access method. As far as OPC client, this paper chiefly studies the data structure, the found of STA thread and the work of STA. At last, this paper designs the interface of real-time database, and then tests the server and the client respectively.This integrated data platform based on OPC provides convenience for user to read and write real-time and history data without concerning about programming the driver. Users can pay more attention to develop arithmetic and excellent control plans. So this platform must be applied widely in the future.