The Research On Distribution Network Reconfiguration For Power Loss Reduction

Network reconfiguration is not only an important method in circulate and control of distribution system, but also an important part of distribution management system. With the development of intelligent technology, it is possible for the use of intelligent algorithm to reduce the eletric network energy loss. The thesis discussed and compared the home and foreign methods and theories of distribution network reconfiguration. It pointed out that the ability of global searching and extensive application in other scopes of genetic algorithm (GA) had proved that it was attracting goal for us to study how to apply genetic algorithm to network reconfiguration. GA has many speciality in network reconfiguration, it will get more applications in network reconfiguration if it can combine with the distribution system peculiarity.At current, the difficuty is infessible solutions produce during GA in the application to distribution network reconfiguration. It greatly reduced efficiency and convergence property of algorithm. From the view of mathematics, it is a problem of solving process of bond for objective fuction.The thesis analysis the fundamental theory and mathematic machanism of GA and its solving method of bond for objective ruction, state the theory of distribution network reconfiguration and the method of equivalent simplifying and identifying the structure of network topology. On the base of it, a network reconfiguration GA design is configured .which adoptes network reconfiguration mathematical mode for power loss reduction: network topology is equivalentiy simplified to the format of tree base and equivalent branch according to radial operation feature of electric distribution network, then a hierarchic genetic algorithm is designed. In the upper module, GA can reduce hunting space by the way of dividing solution space, additionally, an improved GA is developed to reduce unfeasible solutions; in the lower module, the genetic operations can be proceed only in feasible solutions space. At last, the best network topology can be confirmed, namely, the goal of reconfiguration is achieved.The thesis puts forward improved GA operation: improved selection operator by optimum reserved strategy ; crossover adopted part mapping crossover and mutation adopted gemination mutation, that can easily content with radialization and connectedness; grouping and father generation reserved strategy, that can reduce repeated current flow caculation, additionally, efficiency of algorithm can be improved by the way of the lower GA operation executed in several computers.