摘要
弧后介质热恢复特性对断路器开断能力有着显著的影响,该文旨在通过实验手段研究不同因素对高压气体断路器弧后电流特性的影响。首先以126 kV SF6断路器为原型设计了实验样机,之后在不同触头分开时电流相位θ(20°、50°、80°),预期短路电流值I(12、18 kA)及腔体充气压力P(0.5、0.6及0.7 MPa)下进行了一系列开断实验,利用高分辨率的零区设备采集零区电弧电流。结果表明:间隙电弧重燃概率随θ增加而增大,当I=18 kA且P=0.5 MPa时,θ为20°时间隙未发生击穿,而θ分别为50°和80°时弧隙击穿且弧后电流的上升速率分别为1.03和2.08 A/μs;弧后电流及其上升速率随I的增大而增加,当θ=80°且P=0.6 MPa,I为12、18 kA时所对应的弧后电流上升速率分别为1和2.05 A/μs;当θ=80°且I=12 kA时,弧后剩余电流随着P的增大趋向于减小。气体的热开断能力与临界弧后电流存在对应关系,一定程度上可以考虑将弧后电流的临界值作为弧后热击穿的判据。
Post-arc thermal recovery property has a significant influence on the interruption capability of gas circuit breakers （GCB） and the influence of various factors on characteristics of the post-arc current was investigated experimentally in this paper. At first, a test circuit breaker was designed and produced based on a 126kV puffer type SF6 circuit breaker. A series of experiments under different current phase 0（20°, 50°, 80°）, current value l（12kA, 18kA） and filling gas pressure P（0.5 MPa, 0.6 MPa, 0.7 MPa） were carried out then. The high-frequency measuring system was employed to provide assistance for recording basic data on arc current during current-zero period. Comparison of the post-arc current under different conditions reveals that the probability of arc reignition grows with the increase of 0. Ascending speed of post-arc current is 1.03 Aμs and 2.08 A/μs respectively when 0 equals to 50° and 80° while breakdown doesn＇t happen when 0 equals to 20°; post-arc current and its ascending speed current becomes higher with increase of I. Ascending speed of post-arc current is 1 As and 2.05 A/μs respectively when I equals to 12 kA and 18 kA; post-arc current decreases with increase of P. The critical value of the post-arc residual current may be defined as the criterion of the thermal interruption due to the relevance between them.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2014年第21期3512-3517,共6页
Proceedings of the CSEE
基金
国家自然科学基金项目(51222704)~~
