Reliability Evaluation Of Electrical System Under The Conditions Of Various Uncertainty

With the advancement of science and technology and the rapid development ofmodern industry, the equipment technology is developing in the directions precision andcomplication, and then the requirements of the electrical system reliability becomemuch higher. Therefore, it is an urgent problem to evaluate reliability of electrical system. Itis very difficult to attain enough reliability information because of its complexity ofelectrical system structure and mechanism with the limits of human sources，material and financial resources, etc in practice. Consequently, it is of realistic significanceto establish an objective and reasonable reliability evaluation method to deal with theuncertainty of the evaluation.In order to solve the uncertainty of electric system reliability evaluation, this paperproposes a reliability evaluation method based on matter-element theory and evidencetheory. it use matter-element to establish matter-element model of electric system, itquantifies the subordinate relation of various evaluation indexes and evaluation intervalof reliability grades by correlation function, and normalizes it to obtain the belief functionof each index. Then the weight of each evaluation index of electric system is obtained byusing combination weighing method based on entropy weight and G1method, to modifybelief functions of the original evidence. On this basis, using evidence combination rulefuses various evaluation indexes. That paper discusses the application of this method in theelectric system reliability evaluation in detail. Simulation results show that it is to optimizethe evaluation index of electrical system to obtain evidence by matter-element theory, andget more objective and scientific weight by using the composite weight method. Meanwhile,using evidence theory to fuse each evaluation index minimizes the uncertainty inassessment process, and can get more accurate and reasonable results.