摘要
液氮环境中绝缘材料的沿面闪络对超导电力设备外绝缘设计至关重要,为了揭示液氮环境中沿面闪络的发展过程,并研究有效提高超导电力设备外绝缘爬电距离的方法,通过实验对不同直径的圆柱形、不同倾角的圆台形聚四氟乙烯试品在液氮中微妙级负脉冲电压作用下的沿面闪络电压进行了测量,结果发现圆柱形试品随直径增加,沿面闪络电压下降;圆台形试品在45°时闪络电压最高,0°时闪络电压最低。通过与真空、绝缘油中沿面闪络的数据比较以及仿真计算,认为液氮中的沿面闪络与变压器和绝缘油中有相似的闪络机制,沿面闪络是在气化的闪络通道内完成的。实验的结果也为超导电力设备外绝缘设计提供了有益的方法。
The study of surface flashover for insulation materials in liquid nitrogen is very important to outside insulation design of superconducting equipment.In order to reveal the developing process of flashover in liquid nitrogen and study the effective methods to improve the creepage distance of superconducting equipments,the flashover voltages of specimens made of polytetrafluoroethylene were measured under microsecond impulse voltage in liquid nitrogen.The specimens were manufactured as different diameter cylinders and different dip angle truncated cones.By the result of experiment,it is found that the flashover voltages decrease as the diameter increasing for cylinder specimens,for truncated cone specimens,when the dip angle θ is 45°,the flashover voltage is highest,the dip angle θ is 0°,the flashover voltage is lowest.By comparing to the data from vacuum and insulation oil and simulation calculating,it is believed that they have similar flashover mechanism in vacuum,insulation oil and liquid nitrogen environment.The flashover is completed in a gasifying path.The experiment results also provide helpful methods for outside insulation design of superconducting equipments.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2013年第7期170-176,4,共7页
Proceedings of the CSEE
基金
国家高技术研究发展计划项目(863计划)(2009AA03Z209)
国家电网公司重大项目资助(5442DX100001
5442DX110008)~~
关键词
液氮环境
微秒级脉冲
沿面闪络
气化通道
爬电距离
liquid nitrogen environment
microsecond impulse voltage
surface flashover
gasifying path
creepage distance
