摘要
为研究±500 kV直流复合绝缘子的电位分布特性,采用动电容测量法,运用直流线路绝缘子串电位分布测量表,选用FXBZ-±500/300型棒形悬式复合绝缘子作为试品,对比了±500 kV高压直流输电线路工程双悬垂串、双V形串复合绝缘子与单串绝缘子的电位分布特性,发现±500 kV直流双联复合绝缘子串因具有邻近效应而使得其高压端部的分布电压较单串而言要高。根据不同罩入深度、不同组装方式下的均压装置对双联复合绝缘子电位分布特性的影响,给出了双联直流复合绝缘子均压装置合理的结构尺寸和安装形式,可指导电力系统正确选用复合绝缘子均压装置。
From 2002, composite insulators start to be widely used, Nearly 6 to 7 millions of AC and DC composite insulator are operated in the ±500 kV DC electric net in our country,composite insulator is used widely for its hydrophobic characteristic and protection from contamination flashover. To avoid the occurrence of string accident, 500 kV high voltage DC transmission lines use mode of double strings. To research potential distribution of 500 kV high voltage DC composite insulator, moving capacitance measuring method and potential distribution meter of DC transmission lines string is used, and FXBZ- 500/300 stick-suspend composite insulator is used as samples. The potential distribution characteristic of double suspension string and double V sting is compared with single string of the project of 500 kV high voltage DC transmission lines. Since 500 kV DC double sting composite insulator have proximity effect, the distribution voltage of the top of high voltage is larger than that of the single I string. If voltage grading device is used improperly, under the long term load voltage, jacket of shed which is on the connecting interface between insulator metallic accessory and core rod will be eroded and deteriorated. If entrance of moisture appeared, sealing performance will fall down and accident of fall of string will occur because of brittle failure of core rod, the consequence will be very severity. Voltage-grading device of certain cover depth should be fixed on the top of high voltage which is important to the distribution voltage of the top of high voltage. The influence of voltagegrading device of different cover depth and assembly method on the potential distribution of double sting is analyzed. Valid physical dimension and installation form of voltage-grading device of double string DC composite insulator is given and the correct choice of voltage-grading device of composite insulator is proposed. No. 2. voltage-grading device is suggested to be assembled on the top of high voltage of the 500 kV double I string. For 500 kV double V composite insulator sting, assembly method of voltage-grading device should be No. 2 and No. 4. The research result is important to the study of the potential distribution of ±500 kV DC double I composite insulator sting, elongation of operating life of composite insulator, reducing the incidence rate of the accident of loss of string, and assurance the safe operation of electric net.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2006年第9期132-135,共4页
High Voltage Engineering
关键词
±500kV
双联直流
复合绝缘子
电位分布
均压装置
±500kV
double string DC
composite insulator
potential distribution
voltage-sharing device
