Study On The Reconfiguration Of Distribution Network With Distributed Generation Based On Binary Differential Evolution

Reconfiguration is an important means of distribution network optimization, is also an important part of distribution automation research. Currently, distribution network reconfiguration is divided into two kinds: one is the network optimization reconstruction of the normal distribution system (referred to as network reconfiguration), and the other is seivice restoration in distribution system, for the regional of non-fault to recovery power supply (also known as Recovery) . This paper mainly studies on distribution optimizing reconstruction and fault recovery reconstruction when two types of powers which are the micro gas turbine and fuel cell access to the distribution network.According to the distributed power grid interface type this paper analyses their model in the power calculation. In the back/forward flow calculation method, taking into account the distribution network reconstruction can cause branch change, so this paper proposes a topology identification method which is from the network peripheral node began to pushing the root node, and can rapidly update the network topology data and the relationship of the link, and bring the convenient for flow calculation with back and pushing process.In view of the intelligent algorithms has shortcomings of slow convergence speed and easy converging local optimal solution, so this paper adopts differential evolution algorithm which has convergence speed faster, global search and local search ability stronger to distribution network in reconstruction.Considering the distribution network reconstruction process is the switches be opened and closed process, however, the switch's random combination will produce large number of unfeasible solution, so this paper puts forward a method of strategy which is break whole into pieces, the whole solution space is divided into some sub-solution space, make algorithm to search solution space directly, decrease the coding dimension, reduce unnecessary search. In order to avoid producing unfeasible solution in the evolutionary process of differential evolution algorithm, this paper improved the variation operation and crossover operation to improve the efficiency of the algorithm. The results of simulation for 16 nodes, 33 nodes, 69 nodes distribution system with the distributed power show that the reconstruction algorithms is feasible.In view of recovery reconstruction of distribution network with distributed power, needs rapid dividing DG island, this paper proposes a method based on DG feasible island data link table to divided island, and use binary differential evolution algorithmthe to recover the unfault area which is outside of DG island. The results of numerical examples validate that the island dividing method and restore reconstruction algorithm are effective.