摘要
GIS在运行的过程中会不可避免的遭受到操作过电压的作用,为掌握交流(alternating current,AC)和操作冲击(switching impact,SI)电压联合作用对环氧绝缘子绝缘特性的影响。采用AC/SI叠加电压的试验方法,研究了AC电压幅值对AC/SI叠加电压下SF6/N2气体中的沿面放电激发特性的影响,重点分析了滑闪放电的发展趋势、放电数量、首次放电时间和放电持续时间等特征参数。结果表明:首先,随着AC电压幅值的增加,在SI放电阶段,滑闪放电的发生概率显著提高,放电次数略有增加,且首次局部放电出现时间明显提前,在AC放电阶段,滑闪放电的概率同样上升,放电数量显著增多,放电持续时间也相应延长;其次,SI下发生的滑闪放电会对后续AC下的放电产生增强作用;最后,叠加相位对AC/SI叠加下的放电结果存在较大的影响,AC叠加正极性SI电压时,135°的激发的局放现象比45°时的更加剧烈,AC叠加负极性SI电压时,315°激发的局部放电现象比225°更加剧烈。该研究对于深入理解AC/SI叠加电压下的沿面放电特性具有重要的理论意义,也对交流和冲击这一联合电压试验方法的规范化提供了一定参考。
Gas insulated switchgear(GIS)inevitably experiences switching overvoltages during operation.To investigate the influences of the combined action of alternating current(AC)and switching impulse(SI)voltages on the insulation performance of epoxy insulators,this paper studies the effects of AC voltage amplitude on the surface discharge excitation characteristics in SF6/N2 gas under AC/SI superposition voltage.The focus is placed on key discharge parameters,including the development trend of creeping discharge,discharge quantity,inception time of the first partial discharge(PD),and discharge duration.The results reveal that,firstly,with increasing AC voltage amplitude,the probability of creeping discharge during the SI stage significantly increases,accompanied by a slight increase in discharge numbers and an earlier appearance of the initial PD.During the AC stage,both the probability and quantity of discharge events increase markedly,and the discharge duration is extended accordingly.Secondly,the occurrence of creeping discharge under SI voltage enhances the severity of subsequent PDs during the AC.Lastly,the phase angle of the superimposed voltage has a notable effect on the PD behavior.For positive SI polarity,PD activity at a 135°phase is more intense than at 45°,while for negative SI polarity,the PD at 315°is more pronounced than at 225°.This study provides valuable insight into the surface discharge characteristics under AC/SI superimposed voltage conditions and offers theoretical supports for the standardization of combined voltage tests involving AC and impulse voltages.
作者
周阳
秦妍
宋天亮
孟旋
韩旭涛
李军浩
ZHOU Yang;QIN Yan;SONG Tianliang;MENG Xuan;HAN Xutao;LI Junhao(State Key Laboratory of Electrical Insulation and Power Equipment(Xi’an Jiaotong University),Xi’an 710049,China)
出处
《高电压技术》
北大核心
2026年第3期1431-1446,共16页
High Voltage Engineering
基金
国家自然科学基金(52207171)。
