电力变压器灰色关联故障诊断模型的组合权重法

油中溶解气体分析(dissolved gas-in-oil analysis,DGA)是识别变压器故障的重要手段。笔者基于油中溶解气体数据介绍灰色关联理论,给出了基于组合权重变压器故障诊断的灰色关联分析法。在判定变压器故障类型时,各溶解气体其权重不同,利用层次分析法求出各特征气体在诊断变压器故障类型时的主观权重,但各专家通过层次分析法确定指标权重会存在许多主观因素,文中应用灰色关联分析法对其进行调整,消除各专家造成的各指标权重分配不统一,用熵值法确定指标的客观权重,结合熵值法和层次分析法对指标权重值进行综合确定得到组合权重,再将组合权重应用到灰色关联诊断模型中。最后结合实例对诊断方法进行分析讨论,诊断结果表明了该方法的有效性。

Fault Diagnosis Model of Power Transformer Based on Grey Relation with Combined Weights

Dissolved gas analysis(DGA) is an important method to identify the transformer faults.In this paper,the grey relation theory based on the DGA data is introduced,and a grey relation analysis method based on the combined weights for diagnosing transform faults is proposed.For judging a transformer fault type,different dissolved gases are given different weights.Experts determine the subjective weight of each dissolved gas with AHP in diagnosing transformer fault type,however there are too many subjective factors with this method.Therefore,the grey relation analysis is introduced in this paper in order to avoid non-uniform weight distribution caused by experts’ subjective factors,and objective weight of each indicator is determined by using of entropy method.Thus,the combined weights of indicators are obtained and applied to the proposed method for transformer fault diagnosis.Actual case study is performed with this method,and diagnosis results verify its effectiveness.