CAJ | 학술논문

绕击是造成超特高压输电线路雷击跳闸的主要原因，很多学者认为空间电荷是造成绕击事故的原因之一。为深入研究空间电荷对雷电放电的影响，本文搭建了100cm 板-针间隙，对其施加正、负极性操作冲击电压，采用高速摄像系统对放电发展过程进行观测。为定量分析空间电荷对放电发展的影响，测量了正板-针间隙预放电电流，通过提取电荷电流，并对其积分得到空间电荷量的大小。试验结果发现：正、负极性操作电压下，放电发展都是由正极性电极指向负极性电极；正极性操作冲击电压下，放电击中点在针电极头部的概率随着针头部曲率半径的增大而增大。在相同的试验条件下，板-尖头针间隙的空间电荷量最大，随着针电极头部曲率半径逐渐增大，空间电荷量逐渐变小。
요격시조성초특고압수전선로뢰격도갑적주요원인，흔다학자인위공간전하시조성요격사고적원인지일。위심입연구공간전하대뇌전방전적영향，본문탑건료100cm 판-침간극，대기시가정、부겁성조작충격전압，채용고속섭상계통대방전발전과정진행관측。위정량분석공간전하대방전발전적영향，측량료정판-침간극예방전전류，통과제취전하전류，병대기적분득도공간전하량적대소。시험결과발현：정、부겁성조작전압하，방전발전도시유정겁성전겁지향부겁성전겁；정겁성조작충격전압하，방전격중점재침전겁두부적개솔수착침두부곡솔반경적증대이증대。재상동적시험조건하，판-첨두침간극적공간전하량최대，수착침전겁두부곡솔반경축점증대，공간전하량축점변소。
Shielding failure is the main reason for tripping operations of EHV and UHV transmission lines, and many scholars believe that space charge may be one of the causes of these shielding failure accidents. In order to further study the influence of space charge on lightning discharge, a board-needle air gap of 100cm was set up. Under the positive and negative switching impulse voltage, the discharge process of the gap was observed by a high speed video camera system. So as to analyze the influence of the space charge on the discharge development quantitatively, the current through the positive board-needle air gap was measured. Then the charge current was extracted, and the integral of the charge current was calculated to evaluate the amount of space charge. Experimental results show that discharge always develops from the positive electrode to the negative electrode, under both positive and negative switching impulse voltage. Besides, under the positive switching impulse voltage, with the radius of curvature of the head part of the needle increasing, the percentage of discharge striking points on the head of the needle decreases. What's more, under the same test conditions, the amount of the space charge of the board-pointed needle is the largest. With the radius of curvature of the head part of the needle increasing, the amount of the space charge becomes smaller.