The Application Research Of The Improved Network Equivalence Method On The Assessment Of Distribution Network Reliability

Distribution system reliability is a measure of the power supply capacity which according to acceptable quality standards and the required amount uninterrupted supply power to users. Improve distribution system reliability is the whole community needs, it is to implement scientific development, realize the power industry power industry sustained, rapid and healthy development and build a harmonious society needs.This paper briefly introduces the significance of the distribution network reliability, describes the history and the development trend of the studies of the distribution network reliability at home and abroad, summarizes several common methods for distribution network evaluation, and compares the advantages and disadvantages of these methods.This paper proposes an improved network equivalence method for power distribution system reliability evaluation analysis. This method based on the theory of equivalence method, several key issues treatments of this method are discussed and improved. Its main improvements are as follows:(1) Divide complicated distribution network into several units fault zone which according to a certain standard reasonable rules, enabling this problem of how to regulate unified partition equivalent region gets good solve.(2) The components in the same units fault zone have common influence on superior region and junior region, therefore, with the units fault zone as units for equivalence in the process of equivalent, avoid a lot of components of the enumeration;(3) Choose root node of the units fault zone as an equivalent node, avoiding the disadvantages of additional equivalent components.This paper based on a typical distribution network for example. Each load point and system reliability index which is calculated according to the improved algorithm achieved good results which validated the correctness and practicability of this method. Equipment reliability parameter changes on the influence of system reliability are analyzed and the difference of system reliability influence with different contacts is analyzed too. Find out the high efficiency traverse connection mode and the weak links which affect the reliability of the system.