Design And Implementation Of Grid Graphic Display System Based On XML、SOA And QT4

Graphic display component is one of the important parts of the power system software, mainly to complete the graphical functions of power system and various data. In recent years, on the one hand with the introduction of standards IEC61970, SCADA systems need to be standardized. On the other hand, power dispatching center has more and more applications run, demand for the interaction between different systems also forces SCADA system to standardize its graphics, models, etc.In addition, In order to ensure security and high-quality operation of network, power dispatching center will be running multiple applications, such as Supervisory Control And Data Acquisition(SCADA)、Energy Management System(EMS)、Distribution Management System(DMS)and Power Analysis System(PAS). In order to solve the interconnection problem between different systems, to eliminate the presence of the "islands of information" of power systems, the two major domestic power companies have launched their own industry standards. China Southern Grid launched operation service bus specification (OSB). State Grid launched the Enterprise Service Bus(ESB) specifications and remote browsing technology based on G language. In order to meet the demand of the two grid companies, we need to upgrade the existing SCADA system to SOA architecture.This paper uses W3C’s SVG as the monitoring graphics format, and uses C++as a development language, and uses cross-platform interface development tools QT4as file parsing and construction tools. At first the paper introduces the present condition of power graphics system and the advantages of SVG, then the software is modeled and it is divided into three modules, such as graphical display module, graphical analysis module and data updating module, it introduces the realization of the three modules in detail. Finally the paper describes the running effect and how to use the software.In the design progress, the paper is based on the object-oriented design methods, uses a lot of standard design patterns, and uses UML Class Diagram to describe the Object. By studying SCADA System’s theory and some drawing software which belong to Open Source, the paper abstracts vector graphics data structures and uses multi-threading technology to improve the speed of graphics resolution. the paper uses interface and inherit of development language, to enhance the software scalability and maintainability. Now the software can display not only the SVG format files, but also the G language format files and other XML-based format files.