不同温度及厚度下非交联聚乙烯电缆绝缘材料工频交流击穿表现  

Performance of Non-cross-linked Polyethylene CableInsulation at Different Temperatures and Thicknesses in Terms of AC Breakdown at Power Frequency

作　　者：李银格 常柏源 余欣 彭向阳 吴吉 于是乎 姚崇 张宏[2] 高景晖 LI Yinge;CHANG Baiyuan;YU Xin;PENG Xiangyang;WU Ji;YU Shihu;YAO Chong;ZHANG Hong;GAO Jinghui(Guangdong Key Laboratory of Electric Power Equipment Reliability,Electric Power Research Institute of Guangdong Power Grid Co.,Ltd.,Guangzhou,Guangdong 510080,China;State Key Laboratory of Electrical Insulation and Power Equipment,Xi an Jiaotong University,Xi an,Shaanxi 710049,China)

机构地区：[1]广东省电力装备可靠性企业重点实验室(广东电网有限公司公司电力科学研究院),广东广州510080 [2]电工材料电气绝缘全国重点实验室(西安交通大学),陕西西安710049

出　　处：《广东电力》2024年第9期65-71,共7页Guangdong Electric Power

基　　金：中国南方电网有限责任公司科技项目(030000KC22120003(GDKJXM20222600))。

摘　　要：热塑性聚乙烯基电缆绝缘材料具有优于交联聚乙烯(cross-linked polyethylene,XLPE)的电气和机械性能,有望成为新一代绿色环保的电缆绝缘材料。在电缆结构设计中,保守的安全绝缘厚度使得电缆的生产成本增加,降低绝缘层的击穿电场强度;并且在电缆实际运行过程中,绝缘材料往往工作在70~90℃高温环境下;因此针对新型绝缘材料,温度及厚度对其击穿电场强度的影响研究具有工程实际意义。以线性低密度聚乙烯(linear low density polyethylene,LLDPE)/高密度聚乙烯(high density polyethylene,HDPE)共混绝缘材料为研究对象,进行不同温度下(30、70、90、105℃)及不同厚度下的工频击穿实验,研究温度和厚度对其交流击穿的影响。测试结果表明:相较于XLPE绝缘材料,70L-30H(即LLDPE与HDPE在配比为7∶3的情况下熔融共混得到的绝缘材料)具有较高的工频击穿电场强度,在低于工况温度环境下,其击穿电场强度的温度稳定性较高;然而70L-30H的工频击穿电场强度受厚度影响程度略高,但在相同厚度下其击穿电场强度仍明显高于XLPE。上述研究可为热塑性聚乙烯基电缆绝缘材料研发提供参考。Thermoplastic polyethylene-based cable insulation materials have superior electrical and mechanical properties than cross-linked polyethylene(XLPE),and are expected to become a new generation of green and environmentally friendly cable insulation materials.In cable structure design,the conservative design of insulation thickness increases the production cost of the cable and reduces the breakdown electric field strength of the insulation layer.During the actual operation of cables,insulation materials often work in high temperature environments ranging from 70℃to 90℃.Therefore,studying the effects of temperature and thickness on the breakdown strength of new insulation materials has practical engineering significance.This paper takes linear low density polyethylene(LLDPE)/high density polyethylene(HDPE)blend insulation material as the research object and conducts power frequency breakdown experiments at different temperatures(30℃,70℃,90℃,105℃)and thicknesses to study the influence of temperature and thickness on its AC breakdown.The test results show that compared to XLPE,70L-30H(the insulation material acquired by melting blending in which the ratio of LLDPE and HDPE is 7∶3)has a higher power frequency breakdown field strength,and its temperature stability of breakdown field strength is higher in environments below the operating temperature.However,the power frequency breakdown field strength of 70L-30H is slightly more affected by thickness,but its breakdown field strength is still significantly higher than that of XLPE under the same thickness.This research provides reference for the research and development of thermoplastic polyethylene based cable insulation materials.

关 键 词：热塑性电缆绝缘材料 线性低密度聚乙烯 高密度聚乙烯 熔融共混 工频击穿 厚度指数 

分 类 号：TM215.1[一般工业技术—材料科学与工程] TM85[电气工程—电工理论与新技术]