Research On Distribution System Reliability Evaluation With Multiple Wind Farms

Compared with the traditional energy, Wind power has green non-polluting, renewable, huge reserves, wide distribution and use of low cost, economic benefit and other obvious advantages, but its randomness and scheduling, also has brought negative influence for reliability and power quality of power grid. with the increase of installed capacity and the proportion of wind power, especially after a large number of new wind turbine began to put into use, more large wind farms is directly incorporated into the distribution network operation, safe and economic operation of distribution network is facing new challenges. In an age of rapid development of wind power, therefore, an urgent need to research power supply reliability of the power system with more wind farms, which is great significance to the sustainable development of the power system.In this article, through reading a large number of related literature at home and abroad, based on reliability evaluation of ordinary distribution network and comprehensive analysis of various factors affected the accuracy of reliability evaluation, a correction reliability parameter model is established with considering the refusing action of switch components and two weather state of components, and the model with FMEA method are applied to evaluate the reliability of distribution systems with wind farms. This paper also studied the reliability of power distribution network with multiple wind farms which based on Island model, according to the classification model the system load is divided into island inside and outside the island, and reliability index of load inside island is improved obviously. This paper further studied the effect of different island for the reliability of power system which can be better optimized by a reasonable division of the island.With the development of power system, the power grid scale is more and more complex, the data amount and the calculation time in the traditional reliability calculation process is increasing, in order to simplify, this paper established simplified FMEA calculation method based on Network Equivalent, and combined with examples to verify the accuracy of this method. Compared with the traditional FMEA method results, the results of simplified FMEA have some error but within a reasonable scope, and this method can improve calculation efficiency, save computation time. In the case of a region power network in Guangdong, this paper built equivalent model in DIgSILENT simulation platform to simulation analysis the influence on the reliability of the complex power grid because of accessing multiple wind farms. A new multi-objective function, which comprehensively considers the constraints such as reliability indices, network loss and power failure, is proposed under this model, that is used to find the optimal location for the wind generator which provided a certain reference significance for safe operation and further planning of power grid.