The Research On The Data Acquisition Based On The Technique Of OPC And XML

With the rapid development of the network and autocontrol technology,more and more attention has been put on the information system of an enterprise. At present some of the great multinational automation control corporation didn't satisfy the situation that they are only in charge of providing control hardware, software and project, and they also want to have some exploits in the upper information system integration of an enterprise. By this way the longitudinal information system integration could been realized from the supervisory and control system in the bottom to the advanced enterprise applications in the whole industry information system, then real time data could been provided in a better way into the applications of the office automation information processing to meet the demand of various data in a whole enterprise. In this thesis the OPC specification and its unique characteristic in the manipulation between field apparatus and applications have been first introduced, then the OPC XML-DA specification newly released by OPC foundation and an industry data acquisition tunnel which is based on the OPC XML-DA specification have also been presented particularly . The first chapter mainly discusses the OPC specification which is widely accepted and used in industrial process control. Its fundamentals, history and significant effects on process control area are explained in detail .By using this sort of specification, benefits have been brought to the vendors, the developers and final users. Compared with other standards, it has better and more performance. In chapter two a new data presentation format—XML(eXtensible Markup Language) and newly released OPC XML-DA specification are introduced , and this specification can bring new approach to the automation system integration . In chapter three there is a more detailed introduction on how to develop applications based on the OPC specification, a basic structure on the basis of Server/Client, an example of client application is also presented. In chapter four a data acquisition tunnel is proposed and founded, by being expanded it could transmit real time data into the applications of the office automation information processing to meet the demand of various data in an enterprise. In the chapter five every part of the data acquisition tunnel and the function of every part are introduced particularly, how every part of this tunnel is realized is also presented in detail. The last chapter the author made a summary of this paper and what he have get in his whole graduate study .