The Research And Development Of Distribution Network Graphic Short Circuit Calculation System

The procedure of distribution network short-circuit calculation is a important implement for distribution system's faults analysis and substation design. Recently most of short circuit calculation procedures are suitable for transmission system, no graphic interface and operation complicated that limits the extension and application of this software in a certain extent. Thus, according to the speciality of distribution network structure and working mode, it is necessary to design and develop a distribution short-circuit calculation system which has a graphic interface, could get accurate computing results and convenient operation. The innovative idea of graphic components modeled is put forward in this paper, and the arithmetic theory, model truss and design process are analyzed and studied detailedly in this paper.The practical application instances prove that it is a calculational and analytical implement filled with practical values.The paper is composed of three parts which are the analysis of distribution network short-circuit calculation arithmetic, the design and realization of the distribution newtwork graphic short-circuit calculation system and the whole conceiving of short circuit calculation system based on ComGIS. First of all, the familiar fault computation methods in power system are analyzed and introduced in detail, and the fault current compensation method for distribution short calculation is studied in this paper. This method combines the fault current compensation and actual phase sequence presentation. Firstly, it treats the three phase flow calculation results as the state of before-fault, then computes the fault compensation current of fault point by making use of calculational results and fault boundary conditions. At last, it superposes the fault compensation current to fault node. After one back/forward, the fault current of branches and the voltage of nodes could be computed. The method used in three phase flow calculation is layer-by-layer back/forward sweep method which is most efficient.The distribution network graphic short-circuit calculation system is made up of seven parts including database, network graphic editor, man-machine interface, search module, short calculation module, equipments choice module and output module. Database is composed of the network topology database and dynamic database. The network structure, working mode and components' parametrical informations are saved...