Object-Oriented Research And Development Of Power Graphics System

Along with the development of electric power enterprises and computer technology, researchers on graphic system with highly effective rates, strong maintenance and good user interface become an important mission of power analysis system. The power graphics system not only can provide a good graphic platform for each kind of electric power analysis software, but also be able to provide data to later analysis computation supports. The power graphics system is a significant part of electrical network, is an essential tool of the power system computation, simulation and other visible application software of power system. Moreover, to users, it becomes the basic requests of power analysis software.The thesis aims at current situation that the graphics system exited is short of transplantation and generalities, carries on the system analysis and design based on object-oriented thoughts and methods. An entire set of general graph model was given. It designs the relational database using object-oriented thoughts. An expandable database is established to meet power analysis system's needs.This thesis firstly carries on the research of object-oriented technology and exploit methods, using the thoughts of software engineering, agilely applies the object-oriented technology to analysis and design process of electric power graphic system, analyzes the function demands of power graphics system, including document operation, graph operation, view operation, model operation and data management. It designs the graphic object level structural model, discusses the detail of graphic class process, simultaneously, to guarantee overall uniformity of system interface, every graph interface inherits the foundation interface. Then it elaborates documents, windows design process. Through interaction between documents and user interface, it realizes user's each kind of operation.The system database design also follows the object-oriented thoughts and methods. After analyzing the characteristic, the system classification and its good and bad points of object-oriented database, the power graphics system uses the object-oriented relational database design, tries hard to unify the object model and the relational structure. It can not only preserve the object characteristics, but also meet the traditional relations database's needs. Then we discuss expansions from three layer databases patterns to object model, put up with mapping rule from object model to database table, analyze different mapping rule according to different relationshipsamong object classes (one to one, one to many, many to many, as well as inherited relationships and so on), carry on mapping from object model to relational database. And according to the theories of relational database, some controls and adjustments are adopted to data redundancy. It consummates the object-oriented relational database design process.The thesis finally gives ways to realize power graphic system based on object-oriented, discusses some crucial questions which exists in realization process, such as the graph operation realization, connection realizations with other analysis software. Some concrete solutions to realize key techniques are presented..