CAJ | 학술논문

为研究电力设备中不均匀电场下的气体间隙击穿现象，通过搭建局部放电ns级放电电流测试系统，研究了针-板电极下针尖曲率半径和铝箔尺寸变化对放电特性的影响。在无铝箔覆盖时，随着针尖曲率半径的增大，电流脉冲幅值增大，其上升沿、下降沿和脉宽都减小。正极性放电电流幅值大于负极性放电电流，其电流脉冲上升沿和下降沿都要小于负极性放电，这可以用流注理论很好地进行解释。随着铝箔面积的增大，电流脉冲幅值和上升沿都减小，下降沿和脉宽增大。然而负极性脉冲上升沿在铝箔直径为5mm时出现最小值。当介质表面有铝箔覆盖，针尖曲率较小时，放电情形类似于无铝箔覆盖的情况；而当针尖曲率较大时，负极性脉宽小于正极性脉宽，其电流幅值大于正极性脉冲。由此推测，在针尖曲率较大铝箔覆盖时放电机理发生了改变，产生了不同于流注放电的另一种放电。
위연구전력설비중불균균전장하적기체간극격천현상，통과탑건국부방전ns급방전전류측시계통，연구료침-판전겁하침첨곡솔반경화려박척촌변화대방전특성적영향。재무려박복개시，수착침첨곡솔반경적증대，전류맥충폭치증대，기상승연、하강연화맥관도감소。정겁성방전전류폭치대우부겁성방전전류，기전류맥충상승연화하강연도요소우부겁성방전，저가이용류주이론흔호지진행해석。수착려박면적적증대，전류맥충폭치화상승연도감소，하강연화맥관증대。연이부겁성맥충상승연재려박직경위5mm시출현최소치。당개질표면유려박복개，침첨곡솔교소시，방전정형유사우무려박복개적정황；이당침첨곡솔교대시，부겁성맥관소우정겁성맥관，기전류폭치대우정겁성맥충。유차추측，재침첨곡솔교대려박복개시방전궤리발생료개변，산생료불동우류주방전적령일충방전。
It is necessary to investigate the gap breakdown which is usually caused by non-uniform electric field in the electrical set-ups. Consequently, we constructed a measurement system for detecting ns discharge current pulse during partial discharge {PD） to study the effect of the variation of needle curvature and aluminum foil size on the discharge parameters. When the dielectric surface was not covered by aluminum foil , the peak value of current pulse increased ,and its rise part, falling part, and pulse width decreased as the needle curvature increased. The peak value of positive discharge current was higher than that of negative one, and that of its slew and falling part was lower than that of negative one, which could be well explained by the streamer theory. As the area of aluminum foil increased, the peak value and rise part of current pulse increased, and the falling part and pulse width decreased. However, the abnormal phenomenon for negative discharge was found that minimum rise part appeared with relatively small diameter of aluminum foil {5 mm）. With the aluminum foil covering the dielectric surface, the similar result was obtained when the curvature radius was smaller. As curvature radius increased, the pulse width of negative discharge was smaller and its current peak value was larger compared with that of positive discharge. Accordingly, the combination of larger curvature radius and aluminum foil leaded to the transition of discharge mechanism, which was different from streamer.