摘要
针对四川电网输电线路悬式瓷绝缘子断串事故频发的问题,抽样选取了一批运行3~25 a的瓷绝缘子试品,对其老化形式进行了调查分析,并分别通过工频击穿电压试验、冲击击穿试验、机电破坏负荷试验、X射线衍射试验和扫描电镜试验测试了其电气、机械、材料性能。结果表明,悬式瓷绝缘子的老化形式主要包括铁帽炸裂、钢脚腐蚀、瓷体裂纹、釉面蚀损、内部击穿等;运行瓷绝缘子的机电性能分散性较大,产品自身质量对其劣化程度具有显著影响,电气和机械性能劣化程度关联性较小;电瓷材料的显微结构直接影响瓷绝缘子的宏观机电性能,运行状况良好的瓷绝缘子与劣化瓷绝缘子的微观结构存在较大的差异。建议将X射线衍射试验和扫描电镜试验作为瓷绝缘子的采购验收试验之一,并定期对运行瓷绝缘子进行抽样检测,以确保输电线路安全运行。
String breakage accidents of transmission line porcelain suspension insulators occurred frequently in Sichuan Power Grid, therefore, porcelain suspension insulators after 3~25 years of service were sampled to investigate and analyze their aging modes. The electrical, mechanical, and material properties of the samples were evaluated by power frequency breakage voltage test, impulse puncture test, electromechanical failing load test, X-ray diffraction, and scanning electron microscope tests, respectively. The results indicate that the aging modes of porcelain suspension insulators include cap cracking, pin corrosion, radial crack of porcelain, glaze deterioration, and internal puncture. The remaining electrical and mechanical strength of field aged porcelain insulators is highly variable, and the product quality plays a major role in the aging degree of porcelain insulators, while the correlation between the electrical and mechanical strength reduction is weak. The microstructure of porcelain will affect the macro electromechanical properties of porcelain insulators directly. The microstructure of the insulators performed well in service is notably different from that of the insulators deteriorated. It is suggested that X-ray diffraction and scanning electron microscope tests should be used as the means in the process of purchasing and accepting, and the porcelain insulators in service should be sampled for detection regularly, so as to ensure safe operation of transmission lines.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2016年第4期1259-1267,共9页
High Voltage Engineering
基金
中央高校基本科研业务费专项资金(2014207020201)
国网四川省电力公司科技项目(编号略)~~
关键词
瓷绝缘子
输电线路
绝缘子老化
绝缘子掉串事故
绝缘子机电性能
瓷绝缘子微观结构
porcelain insulator
transmission line
insulator aging
insulator string breakage accident
insulator electromechanical property
porcelain insulator microstructure
