基于故障本征证据和特征指标的换流变压器状态评估

Condition assessment of converter transformer based on intrinsic fault evidences and characteristic indicators

针对当前状态评估指标体系对带故障运行的换流变压器"评估死区"的问题,提出一种基于故障本征证据和特征指标的换流变压器状态评估方法。分析了换流变压器阀侧绕组的绝缘特性并选取适用于换流变压器状态评估的故障类型和指标量;采用数据驱动的模糊层次分析法提取故障类型的特征指标,并用关联规则提取故障类型的本征证据集,得到拓宽的状态评估指标体系;引入变权思想突出劣化指标对整体状态估计的影响,以反映换流变压器的真实运行状态,对故障设备的二次评估拓宽了状态评估的应用范围。实例分析结果表明,该方法对换流变压器故障判定的准确率更高,故障识别和故障程度的二次评估使状态评估结果更具实践价值。

Aiming at the dead-zone problem of current condition assessment for faulty converter transformer,a condition assessment method of converter transformer based on intrinsic fault evidences and characteristic indicators is proposed.The insulation characteristics of the valve-side winding of converter transformer are analyzed,and the fault types and initial indicators suitable for condition assessment of converter transformer are selected.To obtain the indicator system of condition assessment,the characteristic indicators of fault type are extracted by data-driven fuzzy analytic hierarchy process,and the intrinsic fault evidence sets for fault types are extracted by association rules.The variable weight is introduced to highlight the impact of the degradation indicators on the whole condition assessment to reflect the actual condition of converter transformer.The secondary assessment of fault equipment broadens the application scope of condition assessment.The case analysis results show that the method has higher accuracy in judging the operation condi⁃tion of converter transformer,and the secondary assessment of its fault degree enhances the practical signifi⁃cance.