Multiobjective Optimal Reconfiguration Research In Distribution Networks

Distribution network reconfiguration is one of the important components of distribution automation. Under the normal operation condition, the distribution controller operates the switch in order to adjust network structure according to the running situation. It can balance load and improve the voltage quality. At the same time, it also can reduce the network loss and improve systematic economy. It must isolate the trouble while breaking down , narrow the range of losing electrical power , and resume supplying power rapidly after the trouble.The deepening of the power market has put forward higher demand to the distribution system. Distribution network reconfiguration can improve distribution systematic security , economy and dependability, so it brings greater economic benefits to the power supply enterprise. Because it's multiobjective, study of multiobjective distribution network reconfiguration has important meanings. Based on summarizing what had been concluded by precursors, differentiated exploration research had been done on multiobjective reconfiguration in distribution networks.At first, this paper have analysed meaning, research current situation and existing problem in the distribution network reconfiguration, then provide the suggestion of improving.In chapter 2, we explain common objectives in distribution network reconfiguration,multiobjective optimize theory, optimize method and theory of picture, which establish the foundation for analyzing the mathematics model and method in distribution network reconfiguration next.In chapter 3, it describes the distribution network into a form of the network that is a kind of structure of changing dissipates on theory of picture in order to simplify the model of building to the distribution network. And it changes "base" into "shape" and "arc" into "node" in the course of reconfiguration. Because balancing load has potential ability to reduce the line loss, wo take balancing load as objective for network reconfiguration.In chapter 4, Distribution network reconfiguration is regarded as multiobjective chaos optimization. Economy, load balanced and improving voltage quality that are optimization objectives are presented. Genetic Algorithms are improved by Niche technology, so that search for the course and speed of progress are improved in the evolution course. Pareto mechanism and decision scheme also are introduced to solved multiobjective optimization in distribution networks.The problem of supply restoration is research emphatically in charter 5. Here the service restoration problem is dealt with in a multiple objective formulation which are the power losses minimizing , maximizing the number of supplied loads and minimizing the switch operation costs. It changes multiple objective into simple objective which is three squared weights. Then supply restoration routes are seeked by heuristic strategies and on which optimization route is analyzed and selected. At last, network operation is optimized by reactive power compensation and the reliability is improved.