低压待合闸线路预伏故障的检测方法  

A Detection Method for Potential Faults of Low-voltage De-energized Power Lines

作　　者：雍静[1] 牛亮亮[1] 曾礼强[1] 

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆市沙坪坝区400030

出　　处：《中国电机工程学报》2012年第7期124-131,共8页Proceedings of the CSEE

基　　金：输配电装备及系统安全与新技术国家重点实验室自主研究项目(2007DA10512709301);中央高校基本科研业务费资助项目(CDJXS11150020);Project Supported by Scientific Research Foundation of State Key Lab. of Power Transmission Equipment and System Security(2007DA10512709301);Project Supported by the Fundamental Research Funds for the Central Universities(CDJXS11150020)

摘　　要：对存在预伏故障的低压待合闸线路进行送电会对相关人员及设备造成危害,为了减少此种危害的发生,根据故障特征,提出一种合闸前利用可控电压对线路进行检测的方法。将2个反向并联的晶闸管构成可控电压发生器,通过调节晶闸管导通角来实现待合闸线路上施加电压大小的可控。该可控电压施加于待合闸线路可以警示触碰线路导体的人员;而对回路阻抗参数的测试和比对,能够检测出可能对人身和设备安全造成危害或不利影响的预伏故障。仿真分析了当人体触碰待合闸线路故障导体时,可有效摆脱的可控电压大小,并针对单相非金属性故障判别困难的问题,通过模拟实验得到了单相非金属性故障的判据,结果表明该判据可有效地对单相非金属性故障和正常负荷进行识别。It may bring hazard to people and equipment when a low-voltage power line with potential faults is energized. In order to reduce the risk, through analyzing the characteristics of potential faults, a detection method using controllable applying voltage was proposed. The controllable voltage generator is composed of two anti-parallel connected thyristors with power supply. The voltage applying to power lines can be controlled by adjusting the conduction angles of thyristors. The gradually increased voltage is able to warn persons against touching the de-energized power line. Meanwhile, comparison of the continuously measured impedances during the controllable applying voltage increase process is able to detect the potential faults existed on the de-energized power line. Simulation results determined the maximum voltage that can be extricated from when a human body touches the de-energized power line. The criterion of single-phase non-metallic faults, which is difficult to be identified, was also obtained and verified with experiments.

关 键 词：待合闸线路 可控电压 预伏故障 阻抗 低压 系统 

分 类 号：TM77[电气工程—电力系统及自动化]