相电源馈入中性点的配电网接地故障相主动降压消弧装置及其应用  

Arc Suppression Device for Actively Reducing Grounding Fault Phase Voltage Based on Phase Power Supply Feedback in Distribution Network and Its Application

作　　者：曾祥君[1] 王沾[1] 喻锟[1] 彭红海[2] 卓超[1] 周犊垚 ZENG Xiangjun;WANG Zhan;YU Kun;PENG Honghai;ZHUO Chao;ZHOU Duyao(Hunan Province Key Laboratory of Smart Grids Operation and Control,Changsha University of Science and Technology,Changsha 410004,China;College of Electrical and Information Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]长沙理工大学智能电网运行与控制湖南省重点实验室,长沙410004 [2]湖南大学电气与信息工程学院,长沙410082

出　　处：《高电压技术》2022年第9期3356-3366,共11页High Voltage Engineering

基　　金：国家自然科学基金重点项目(51737002;52037001)。

摘　　要：针对传统消弧线圈不能完全抑制间隙性弧光过电压及故障相转移装置在发展性故障情况下存在引发严重相间接地短路过电流的风险,提出一种相电源馈入中性点的配电网接地故障相主动降压消弧方法。发生单相接地故障时,从接地变压器二次侧提取与故障相相电势相反的线电压向量,通过注入变压器升压馈入至配电网中性点,强迫故障点电压至电弧重燃电压以下,实现熄弧并阻止电弧重燃,有效抑制间隙性弧光接地过电压和不停电处理可恢复性绝缘故障,并研制出由接地变压器、单相注入变压器等相关设备组成的主动降压消弧装置。在10kV真型配电网试验场通过大量实验测试和挂网运行验证了所建议方法和装置的可行性和可靠性。通过与现有同类技术比较,该装置具有性能好、兼容性强、造价低、短路电流风险小等优势。Gap arc overvoltages can not be completely suppressed by the traditional arc suppression coil,and serious phase-to-phase grounding short-circuit overcurrent can be caused by the fault phase transfer device in the case of developmental fault.Therefore,an active step-down arc suppression method of ground fault phase based on power supply potential feedback is proposed.When a single-phase grounding fault occurs,the line voltage vector opposite to the phase potential of the fault phase is extracted from the secondary side of the grounding transformer and fed to the neutral point of the distribution network by injecting transformer boost,so that the voltage of the fault point is forced to be below the arc reignition voltage,the arc extinguishing and preventing arc reignition can be realizied,the intermittent arc grounding overvoltage can be effectively suppressed,and recoverable insulation faults can be handled in the live working conditions.An active step-down arc extinguishing device is developed,which consists of grounding transformer,single-phase injection transformer,and other related equipment.The feasibility and reliability of the proposed method and device is verified through a large number of experiments and tests in the 10 kV distribution network true laboratory and on-site operation of the substation.Compared with the existing similar technology,the device has the advantages of good performance,strong compatibility,low cost and low risk of short-circuit current.

关 键 词：配电网 接地故障 主动降压消弧 接地变压器 相电源馈入中性点 

分 类 号：TM862[电气工程—高电压与绝缘技术]