Design And Realization Of SCADA System Based On Web Services And Ajax

SCADA system is widely used in power system and electrify railroad. With the improvement of opening demand for power companies, on the one hand, the demand for the SCADA based on Web is increasing; on the other hand, SCADA often faces interactive and information-sharing needs with other system. The current SCADA system has been exposed the problem that the data model is private, the interface is not open, upgrade, expand and maintenance are difficult, this restricts greately the opening ability of SCADA to users. In response to these issues, in this paper it studies and develop a standardized, open, distributed, loosely coupled Web SCADA with Web Services technology and Ajax technology as the core and in combination with IEC61970 CIM.Firstly, this paper analyzes the traditional component and its lackness, and dicusses Web Services technology. It analyzes traditional Web application and its lackness, and dicusses Ajax technology, also puts forwords J2EE platform as development platform of system through comparing popular Web Services development platform and designs entire system architecture based on Web Services and Ajax technology through the analysis on business model.Secondly, this paper puts forword a method of adding hibernate persistence layer between business logic layer of real-time database subsystem web services and database through comparing three layer configuration with persistence layer software configuration. Though the sequence diagram, it describes the design idea of real-time database subsystem Web Services interface, and taking all fectching remotely telemetry interface as an example to test the interface, test result indicates that system has the characteristics of open, has solved the problemes that the data model is private, the interface is not open.Thirdly, this paper designs communication subsystem web services through sequence diagram based on communication software of HY2004, and taking remotely controlling interface as an example to test the interface, test result indicates that the program is feasiable, and makes full use of the communication software of HY2004, reduces the development investment.After that, this paper puts forward SVG technology as a monitor screen graphics display method, through comparing the way of several monitorin graphics, and describes the design idea of models such as permission management, remotely signaling, remotely telemetry, remotely controlling, failure alarm and real-time curve, and also describes the implementation method of each model in detail, has solved the problems that upgrade, expand and maintenance are difficult.Finally taking the shi de power SCADA project as an example to test the system, given the test results, practice results indicate that system has a good open, real-time, reliability and can meet the actual demand better, and verifies that SCADA based on Web Services technology and Ajax technology is feasible and effective.