±800kV楚穗直流线路复合绝缘子局部温升与缺陷等级研究

Local Temperature Rise and Defect Grade of Composite Insulators for ± 800 kV Chusui DC Transmission Line

局部异常温升会对复合绝缘子的绝缘性能造成不可逆转的伤害,严重威胁电网的安全运行,近年来复合绝缘子异常温升缺陷逐渐凸显且呈现越来越严重的趋势。针对±800 kV楚穗直流输电线路在线运行复合绝缘子的异常温升情况,利用红外测温技术和扫描电子显微镜法对复合绝缘子异常温升缺陷进行全面深入研究,发现造成楚穗直流线路复合绝缘子异常温升的主导原因为绝缘子的内部缺陷。依据复合绝缘子局部异常温升的不同形态将其划分成不同温升类型,在研究复合绝缘子局部异常温升状态、温升类型与缺陷等级关系的基础上,提出将复合绝缘子温升缺陷划分为轻度、一般、中度、严重和紧急共五类不同缺陷等级,并针对性的制定了运维检修策略,为楚穗直流复合绝缘子的在线监测与精细化运维提供了可靠的辅助决策。

Local abnormal temperature rise will cause irreversible damage to the insulation performance of composite insulators and seriously threaten the safe operation of the power grid. In recent years,the defect of abnormal temperature rise of composite insulators is becoming more and more serious. In this paper,aiming at the abnormal temperature rise of composite insulators for ± 800 kV Chusui DC transmission line,the infrared temperature measurement technology and scanning electron microscope method are used to conduct a comprehensive and in-depth study on the abnormal temperature rise defects of composite insulators. It is found that the main reason for the abnormal temperature rise of composite insulators is the internal defects of the insulators. Based on the study of the relationship between local abnormal temperature rise of composite insulators,temperature rise types and defect grades,the author proposes to divide the temperature rise defects of composite insulators into five different defect grades: mild,general,moderate,serious and urgent,and formulates maintenance and repair strategies accordingly,which provides reliable auxiliary decisions for on-line monitoring and fine maintenance of Chusui DC composite insulators.