Investigations, through a sample evaluation, aiming to evaluate the cause of the high-frequency oscillations presented by distribution transformers in impulse tests reveal that internal imperfections, such as cavities and floating particles, cause these oscillations.

中文翻译：

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雷电-脉冲电压测试期间配电变压器呈现的高频振荡差异的研究

通过样本评估进行的调查旨在评估配电变压器在脉冲测试中出现的高频振荡的原因，结果表明内部缺陷（例如空腔和漂浮颗粒）会导致这些振荡。