Research Of Web Service-Based Real-Time Data Access Platform For SCADA System

With the rapid development of power market and information system for power system, more and more applications need real-time operating data of electrical grid from SCADA system. Traditional real-time database for the SCADA system exposed a lot of problems when it integrates with external systems. For example, it is diffult for functional expansion, information exchange within different systems or applications, and coordination with other systems provided by different manufacturers. Current real-time database for SCADA system is based on proprietary database. This means that different data formats and application interfaces are used by different manufacturers. When they come to the requirement of integration, the only solution is that specialized softwares or special communication protocol are needed. This has greatly restricted the SCADA system to share information with other information systems. In order to solve all problems above, the study of the real-time data access platform for SCADA system using the latest Web Services technology is discussed in this thesis.Firstly, the requirement for SCADA system to integrate with other systems and problems of traditional real-time database for SCADA system are analyzed. The research issue of real-time data access platform for SCADA System with Web Services technology is introduced here.Secondly, the thesis discusses of the key technologies for real-time database system, analyses Web Services technology from the aspects of system architecture, the protocol stack and other technical content, and compares it with the traditional component technologies, such as COM, DCOM, CORBA, EJB,etc.Thirdly, the thesis discusses some characteristics of two main development platforms for Web Services:.NET and J2EE. Based on its open, efficient and the extensive support for Web Services standards,.NET is chosen as the development platform here. Then the framework, the class library, data access, the development of languages, and Web Services technology of.NET platform are analyzed in detail.After the study of real-time database Web Services and Web services development platform, the design for a Web Services-Based real-time data access platform for SCADA system is proposed. Its system architecture, data structure, as well as the realization of Web Services are described in detail.Finally, the system is implemented by C# under.NET platform, and its cross-platform characters are tested through different client implemented by JAVA and VB. The test shows that Web Services technology owns good Characteristics, such as Cross-platform, and highly integrated capability. This Web Services-Based system is easy to realize resource integration, data sharing, interface standardization, as well as Management Integration in the future.Owe to the loosely coupled, reusabe, and standard characteristics of Web Services, this access platform provids the open, standardized interface for real-time data access of SCADA system, and has many advantages, such as wide data sharing, resource integration, flexibility, and scalability, etc..