开发新的加速衰老测试,以比较基于纤维素的不同绝缘纸质量的质量
Draginja Mihajlovic1, Valentina Vasovic1, Jelena Lukic1
1Laboratory for Testing and Calibration, Electrical Engineering Institute Nikola Tesla, Koste Glavinica 8a, 11000 Belgrade, Serbia.
Polymers
|June 10, 2023
概括
循环老化测试加速了变压器纸的绝缘降解,揭示了更高含水量更快的老化. 这种方法有效地比较绝缘纸质量.
科学领域:
- 电气工程 电气工程
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 变压器绝缘系统,包括油和纤维素纸,随着时间的推移而降解.
- 评估变压器绝缘的质量和剩余寿命对于电网可靠性至关重要.
- 现有的衰老测试在各种条件下可能不准确地反映现实世界的退化.
研究的目的:
- 提出和验证一种新的加速老化测试方法,用于变压器纸张绝缘质量的确定.
- 调查循环与连续老化对油/纤维素绝缘系统的影响.
- 评估初始水分含量对纤维素绝缘材料老化速度的影响.
主要方法:
- 对Kraft和热升级纸张进行了加快老化测试,使用矿物和天然油在150°C至180°C的温度下进行.
- 实验包括干燥 (≤0.5%水分) 和湿 (3-3.5%水分) 纤维素绝缘.
- 测量了降解标记物,如聚合度,抗拉强度,衍生物和酸度等.
主要成果:
- 纤维素绝缘材料的循环老化速度是连续老化速度的1.5-1.6倍,这归因于增强的水解机制.
- 与干燥条件相比,纤维素绝缘材料最初的高含水量使老化速度加快了两到三倍.
- 不同的老化条件显著影响了纸张和油的降解标志物.
结论:
- 拟议的循环衰老测试方法提供了一种更快,更有效的方法来评估变压器纸隔热质量.
- 了解湿度和老化周期的作用对于准确的绝缘寿命评估至关重要.
- 这种方法可以在加速降解下可靠地比较不同类型的绝缘纸.
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