The Distribution Network Reliability Assessment Considering The Distribution Generation

Nowadays, with the development of Distributed Generation (DG), the DG technology will play an increasing important role in Electricity Power System. DG can not only improve the energy efficiency, but also decrease the emergences of short-of-electricity. In all, the DG is the optimal choice for long-term energy development, environment protection, and peaceful society.With the penetration of DG into distribution system, the reliability assessment model is changing. The output power of DG is much more random compared with the traditional power. Furthermore, the traditional assessment model is a radial network, in which the single power source provides the energy to several feeders. Once a fault happened in a feeder, the loads collected with the feeder would be out of energy. With the DG into distribution system, the radial network turns into a multi-source network, and the assessment model is also different with the traditional one when DG is operating in island mode.The paper proposes a new assessment model considering the DG, which can handle the influence of DG to the distribution system. 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. Then 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 depth-first search and breadth-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.