Research On The Reliability Assessment Of Urban Distribution Network And Its Economy

With the rapid development of our social economy, power consumption gradually increases.At the same time, users have higher demand for the power quality and power supply reliability,especially in the big background of smart grid. The distribution system connects the power system and users,which is an important link of the entire power system.Once it has fault or maintenance, it must cause the interruption of power supply for users.So the reliability of distribution system occupies a veryimportant position in power system reliability.This paper firstly introduces the importance of reliability and economic evaluation and its development at home and abroad. It mainly elaborates the research status of reliability evaluation theory and economic analysis, which pointes out the distance between our country and foreign couutries in distribution system reliability evaluation and its reason.And then reliability model and reliability evaluation index system are established which provides a basis for the reliability evaluation of city distribution system. It introdces the operating characteristics of city distribution system and the concept of reliability evaluation in detail, establishing the reliability model of component and system and putting forward index system of load and system suitable for ciyt distribution system.Then the simplified principles of system components and shortest route equivalent method of city distribution system reliability are introduced in detail.An example is uesd to verify the theory and measures of improving distribution system reliability are put forward according to the caculation results.Finally the contradiction between reliability and economy of power distribution system is introduced.It analyzes the methods of economic evaluation and establishes the optimization model of reliability and economy which is verified by a practical example.