摘要
为有效降低雷击断线的概率,根据导体的熔点和电弧特性,从材料力学和电磁力学角度定性地分析了绝缘铝导线雷击断线机理,认为短路电流电弧弧根稳定燃烧的位置主要与雷电流大小、短路电弧电磁力矢量、工频电流产生的电磁力矢量和高、低压电极的相对位置有关。铝的熔点低、弧根固定燃烧和高、低压电极电弧轴向的交变电磁力所产生的反作用力以及导线因自重产生的张力是绝缘导线断裂的主要原因,雷击断线介于脆性断裂和韧性断裂之间。优化了直线杆和耐张杆导线固定外的防雷和绝缘设计,对绝缘导线制造工艺提出了改进建议,易击段直线杆处增加引弧跳线,金属绑扎线改为芳纶纤维绳,耐张线夹采用压缩型,直接固定导体,将弧根引到耐张线夹上,避免雷击断线。
In order to effectively reduce the probability of lightning-caused break, based on the conductor＇s melting point and electric-arc characteristic, from the angles of materials mechanics and electromagnetism, the lightningcaused break mechanism of insulated aluminum conductor is analyzed qualitatively; It is considered that the steady burning location of short circuit current arc root is mainly related to the vector of short current arc electromagnetic force, vector of electromagnetic force produced by the power frequency current, and the relative locations of high voltage and low voltage electrodes. The aluminum＇ s low melting point, the arc root＇ s fixed burning, the reacting force produced by the axial alternating electromagnetic force of arc formed between hlgh-voltage and low-voltage electrodes, and the tension produced by the dead weight of conductor, are the main reasons for regular break of the insulated conductor. The features of lightning-caused break are between brittle break and tough break, the design of lightning prevention and insulation at the straight pole and strain pole where the conductor is fixed is optimized, and suggestions for improvement are made for the insulated conductor＇s manufacture process. Are-leading jumper can be installed at the straight pole where lightning stroke is easily to occur, the aromatic vinylon fiber wire can be used to replace the metal binding wire, compact tension clamp can be used to directly fix the conductor, and lead the arc root to the tension clamp, in order to avoid lightning-caused breaking. Using insulated steel reinforced aluminum alloy conductor is also an effective measure to improve the capability against lightning-caused wire break.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2007年第1期102-105,共4页
High Voltage Engineering
关键词
导体熔点
电弧特性
绝缘导线
雷击断线机理
措施
conductor melting point
electric-arc characteristic
covered conductors
mechanism of lightning-caused breaking
measure
