在热老化下,XLPE电缆绝缘的结构变化和非常低频非线性介电反应
Can Wang1, Xuetong Zhao1, Jingqi Qiao1
1State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, Shapingba District, Chongqing 400044, China.
Materials (Basel, Switzerland)
|June 28, 2023
概括
本研究评估了使用结构分析和非常低频 (VLF) 介电反应的交联聚乙烯 (XLPE) 电源电缆的热老化. 结果揭示了介电性质的显著变化,表明XLPEPE是XLPE.
科学领域:
- 材料科学 材料科学 材料科学
- 电气工程 电气工程
- 聚合物科学 聚合物科学
背景情况:
- 交联聚乙烯 (XLPE) 是电源电缆中的关键绝缘材料.
- 热老化对XLPE绝缘材料的长期性能和可靠性产生重大影响.
- 了解老化机制对于预测电缆寿命和防止故障至关重要.
研究的目的:
- 评估在各种热老化条件下,电源电缆中的XLPE绝缘材料的老化状态.
- 研究结构变化与非常低频 (VLF) 非线性介电反应之间的相关性.
- 描述热老化XLPE的非线性介电性质.
主要方法:
- 在90°C,120°C,150°C的加快热老化实验,持续时间不同 (240小时,480小时,720小时).
- 福里埃变换红外光谱 (FTIR) 和差分扫描热量计 (DSC) 用于物理化学性质分析.
- 测量VLF介电光谱 (1mHz到0.2Hz) 和电压-电流 (U-I) 歇斯底里曲线.
主要成果:
- 热老化导致XLPE绝缘材料的物理化学特性发生显著变化.
- 超高频介电谱显示,随着老化,导电能力和介电损失发生了实质性的变化.
- 由U-I歇斯底里体现的非线性介电性质被发现是热衰老的敏感指标.
结论:
- VLF非线性介电反应是一种有效的方法来评估XLPE绝缘材料的热老化状态.
- 由于衰老的结构和物理化学变化直接影响介电行为.
- 这些发现有助于改善电源电缆的状况监测和寿命评估.
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