配网环网柜肘型头早期故障动态特性  

Incipient Fault Dynamic Characteristic of Elbow Type Cable Joint in the Distribution Ring Main Units

作　　者：段常坤 刘亚东[1] 严英杰[1] 王科 李维 江秀臣[1] DUAN Changkun;LIU Yadong;YAN Yingjie;WANG Ke;LI Wei;JIANG Xiuchen(School of Electronic Information and Electrical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Electric Power Research Institute,Yunnan Power Gird Co.,Ltd.,Kunming 650217,China)

机构地区：[1]上海交通大学电子信息与电气工程学院,上海200240 [2]云南电网有限责任公司电力科学研究院,昆明650217

出　　处：《高电压技术》2025年第2期742-752,共11页High Voltage Engineering

基　　金：国家电网公司科技项目(5100-202356772A-3-6-ZX)。

摘　　要：肘型头易在长时间投运后老化,在其与套管的接触界面处形成气隙,在凝露渗入后发生可自清除的电弧早期故障,并在多次累积后导致燃烧、爆炸等严重事故。研究肘型头早期故障的产生机理与发展过程并提取故障信号特征,可指导肘型头早期故障的检测与辨识,提高配电线路的可靠性与运维水平。该文基于磁流体动力学仿真模型与现场试验对早期故障的发展过程、电弧形态与故障电流波形特征进行了研究。结果表明:肘型头早期故障可分为“水带靠近-水带沸腾-水带干涸”3个阶段;“靠近”阶段中,故障电流零休的持续时间逐渐减小,直至消失,向正弦波形转变;“沸腾”阶段中,故障电流零休的持续时间先增后减,存在多次“无零休-存在零休-无零休”的转变;“干涸”阶段中,故障电流由“无零休”向“存在零休”转变,且零休的持续时间逐渐增加,直至电弧完全熄灭。研究结果为进一步实现肘型头早期故障的检测奠定了基础。Elbow-type cable joints age easily after a long period of operation.An air gap can form at the contact interface between the elbow-type cable joint and the bushing.Self-cleaning incipient arc fault happens after condensation penetrat-ing into the narrow air gap.The cumulative damage caused by multiple incipient faults can cause serious accidents such as combustion and explosions.The study of the generation mechanism and development process and the extraction of fault signal characteristics can guide the detection and identification of elbow-type cable joint incipient faults and improve the reliability and operation level of distribution lines.In this paper,the development process of incipient faults,the arc morphology,and the fault current waveform characteristics are investigated based on magnetohydrodynamic simulation models and field experiments.The results show that the elbow-type cable joint incipient fault can be divided into three stages named“water belt is close to the electrode-water belt boils-water belt dries up”.The duration of the fault current zero time in the first stage gradually decreases until it disappears,and the waveform transforms into a sinusoidal wave-form.The duration of the fault current zero time in the second stage first increases and then decreases.There are several times of“no zero rest-the existence of zero rest-no zero rest”transition in this stage.The duration of the fault current zero time in the third stage gradually increases until the arc is completely extinguished.There is a“no zero rest-the ex-istence of zero rest”transition in this stage.The results of the study provide a basis for further realization of the detection of elbow type cable joint incipient faults.

关 键 词：肘型头 电缆配电线路 早期故障 磁流体动力学 波形特征 

分 类 号：TM643[电气工程—电力系统及自动化]