摘要
为了研究交联聚乙烯(cross-linked polyethylene,XLPE)电缆经历短时高热运行后绝缘性能的变化,通过对短电缆样本进行短时高热老化来研究其聚集态结构与介电性能的变化及关联性。首先对10 kVXLPE电缆样本分别在90、105、120、135和150℃下热老化2 d,然后将所有样本在90℃下热处理90 d,最后采用极化–去极化电流测试、击穿电压测试对热处理前后的样本进行电气性能表征。为了解其聚集态结构变化,采用差示扫描量热测试、傅里叶红外光谱测试对热处理前后的样本进行理化性能表征。结果表明,当电缆经历短时高热运行后,若短时高热温度处于XLPE熔融温度范围内,绝缘的界面极化强度、抗氧化剂消耗速率会减小;而当短时高热温度超过XLPE熔融温度时,绝缘的界面极化强度、抗氧化剂消耗速率会增加。这一结果表明了当电缆短时高热运行温度处于XLPE熔融温度范围时,之后电缆热氧老化进程会因XLPE重结晶效应而被减缓;当温度高于XLPE熔融温度时,之后电缆热氧老化进程会由于XLPE发生热裂解而被促进。
To understand the changes in insulation properties of cross-linked polyethylene(XLPE) cables after short-term high-temperature operation, we investigated the changes and correlation between the aggregated structure and dielectric properties of short cable samples subjected to short-term high-temperature aging. First, we carried out high-temperature aging for 2 days at 90, 105, 120, 35, and 150 ℃ for 10 kV XLPE cables, and then thermally treated at 90 ℃ for 90 days.Finally, the electrical properties of the samples before and after thermally treated were characterized by polarization and depolarization current test and breakdown voltage test, and the physical and chemical properties of the samples before and after thermally treated were characterized by differential scanning calorimetry and Fourier transform infrared spectroscopy. The results show that when the cable experiences short-term high-temperature operation, if the short-term high temperature is within the range of XLPE melting temperature, the interfacial polarization strength and antioxidant consumption rate of insulation will be reduced;while when the short-term high temperature exceeds the XLPE melting temperature, the interfacial polarization strength and antioxidant consumption rate of insulation will increase. The results show that when it is in the XLPE melting temperature range, the subsequent thermal oxygen aging process of the cable is slowed down by the recrystallization effect of the XLPE;when the short-term high-temperature operating temperature of the cable is above the XLPE melting temperature range, the subsequent thermal oxygen aging process of the cable is facilitated by the thermal cracking of the XLPE.
作者
陈祎林
周凯
林思衍
徐庆文
伍亚萍
王子康
CHEN Yilin;ZHOU Kai;LIN Siyan;XU Qingwen;WU Yaping;WANG Zikang(College of Electrical Engineering,Sichuan University,Chengdu 610065,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2023年第2期588-596,共9页
High Voltage Engineering
基金
国家自然科学基金(51877142)。
关键词
XLPE电缆
热老化
短时高热
抗氧化剂
界面极化
XLPE cables
thermal aging
short-term high temperature
antioxidant
interfacial polarization
