干式空心电抗器匝间过电压的诊断判据

Diagnostic Criterion of Turn-to-turn Overvoltage Test in Dry-type Air-core Reactor

匝间绝缘缺陷是引发干式空心电抗器故障的主要原因,为更加迅速、准确地判断电抗器的匝间绝缘状况,通过匝间过电压实验研究,结合仿真计算和和现场检测,提出了基于振荡频率、衰减系数及其标准离差率的定量化判断标准。针对振荡频率提出1%和2%两个判据：即标定电压和试验电压下频率偏移未超过1%的属于正常状态;偏移超过2%时判断该电抗器存在匝间绝缘缺陷,定义为严重状态;偏移超过1%但未超过2%的,该电抗器可能存在匝间绝缘缺陷,定义为注意状态,需要进一步诊断确认。针对衰减系数提出5%和10%两个判据。针对衰减系数标准离差率提出10%和30%两个判据。这些定量化判据和判断流程,可以准确有效地评估干式空心电抗器的匝间绝缘状况,为设备的运行维护和故障诊断提供参考。

Turn-to-turn insulation defects in dry-type air-core reactors are the main cause of equipment failure.Consequently,we proposed the diagnostic criteria based on oscillation frequency, attenuation coefficient, and standard deviation. For oscillation frequency, if the frequency deviation of the rated voltage and the test voltage is more than 2%, the reactor has a turn-to-turn insulation defect and is in a serious state. If the deviation is between 2% and 1%, the reactor may have turn-to-turn insulation defects and is in an attendant state. If the deviation does not exceed 1%, the reactor is in a normal state. For attenuation coefficient, two criteria such as 5% and 10% are established. For standard deviation, two criteria such as 10% and 30% are established. A standardized judgment flow can be used to assess the turn-to-turn insulation of dry-type air-core reactor, which provides a reference for the operation and maintenance of the reactor equipment.