Distribution Network Reliability Analysis Considering The Impacts Of Distributed Generation

With the rapid development of our social economy,the requirement of the power quality is increasing. As the distribution system located in the end of the power system,directly connected to the users, its reliability problem is one of the key factors of power quality.It plays an important role in the reasearch of power system reliability.Along with the development of power technology, distributed generation has been connected to power system widely.It has important practical significance to reasearch the influences of distributed generation to power system reliability.Based on several reliability evaluation methods, the paper presents a method using minimal path principle and interval arithmetic to assess the reliability of complicated distribution system.The method changes the reliability evaluation formula into interval form and takes the uncertainty of all of the parameters into account.It also uses the interval inversion formula to strict bounds of the indices.In some extent,the method avoids the influences caused by the lacking of original parameters and the imprecision of statistics.It is more in accordance with actual project.Through several different ways of wiring,the paper analyzes the influences of the switch, fuse, spare transformer to the distribution system reliability.The reliability assessment results will greatly due to the interconnection position, interconnection way and operation manner of DG. At first,based on the DG characteristics, the paper builds the resource model which is applicable to the distribution network reliability assessment model with DG. And the paper validates the importance of loads in power network and builds a separation islanded mode method,with the maximum of equivalent loads as the aim of function. It uses the breadth-first search and depth-first search technology to solve the problem.Besides,the paper makes a new version of the minimal path method in the traditional assessment analysis to suit for the algorithm considering the DG An IEEE RBTS Bus6 system is applied to testify the efficiency of the modified model.The case results also show that DG can increase the reliability of distribution system and the capacity and position of DG can effect the reliability of distribution system.