Study Of Method Of Power Flow Analysis And Calculation For Distribution Systems And Developing Of Database

Distribution systems analysis is one of the three main functions of the distribution management system, and power flow calculation is the foundation of distribution systems analysis. So arithmetic of power flow for distribution systems is the main field of distribution systems now. What the paper researches are arithmetic of power flow for distribution systems and developing of database. On the basis of current arithmetic of power flow, the paper mainly proposes two kinds of arithmetic from two different facets. One is arithmetic of power flow based on threaded binary tree for distribution systems. The method thinks of every feeder as a tree, and store structure is expressed as child-brother-parent notion. So a tree is transformed to a binary tree, then a threaded binary tree is coming into being at the time of tracking it. A new method of power flow is coming into being when combining threaded binary tree and forward sweeping method. The paper transforms it into two radial networks with Thevenin's theorem and superposition theorem when there is a meshed network. Forward sweeping method for radial distribution systems that makes use of feature of the arithmetic and radial distribution in the facet of programming, makes programming very easy by use of threaded binary tree, and makes time for calculation shorter. It is showed that the method converges very fast and holds little EMS memory in a computer. Otherwise, the paper proposes power flow method based graph theory for distribution networks on the basis of above method. The method is better in the facets of programming, node's denotation and disposing running fashion. The other is a new power flow method based on stream-graph for distribution systems. The method makes use of Char-Mai stream-graph for power flow calculation in place of conventional pure numeric analysis. The method forms network topology first, then forms Char-Mai stream-graph, according child graph and separate product, and gains the whole linear equation solution at last. The method avoids solving nonlinear equations, overcomes the shortcomings of traditional numeric calculation. Otherwise, the paper has developed software for QuanZhou's distribution systems power flow on the basis of researching arithmetic of power flow for distribution systems.