The porcelain insulator incipient fault (PIIF) is a self-clearing discharge process caused by water entering the crack of the porcelain insulator. It will not result in a tripping operation but may evolve into a permanent grounding fault after multiple occurrences, leading to various types of accidents, such as wire breaks, power outages, fires, and personal electric shocks. This paper uncovered the mechanisms behind the initiation and evolution of the PIIF. Unique characteristics of the PIIF are analyzed from aspects such as the starting time, the power-resistance variation trend, and the fault duration. The characteristics were verified and supplemented by field experiments, and the influence of the insulator models, neutral grounding modes, and the number of discharges on these characteristics was analyzed. The results lay the foundation for the identification and pre-warning of PIIF.

中文翻译：

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非有效接地系统分布瓷绝缘子早期故障机理及电气特性研究


瓷绝缘子初期故障（PIIF）是水进入瓷绝缘子裂纹引起的自清除放电过程。它不会导致跳闸操作，但多次发生后可能演变成永久性接地故障，导致断线、停电、火灾、人身触电等各类事故。本文揭示了 PIIF 的启动和演化背后的机制。从启动时间、功率电阻变化趋势、故障持续时间等方面分析了PIIF的独特特性。通过现场试验对这些特性进行了验证和补充，并分析了绝缘子型号、中性点接地方式、放电次数对这些特性的影响。研究结果为PIIF的识别和预警奠定了基础。