配电网弧光接地主动转移型消弧技术  

Active Transfer Arc-Extinguishing Technology of Arc Grounding in Distribution Network

作　　者：李景丽[1] 任俊跃 赵子敬 LI Jinglil;REN Junyue;ZHAO Zijing(College of Electrical Engineering Zhengzhou University,Zhengzhou 450001,China;State Grid Jiyuan Power Supply Company,Jiyuan 459000,China)

机构地区：[1]郑州大学电气工程学院,郑州450001 [2]国网济源供电公司,河南济源459000

出　　处：《电瓷避雷器》2023年第1期116-123,132,共9页Insulators and Surge Arresters

摘　　要：我国城市中低压配电网电容电流急剧上升且消弧线圈补偿效果欠佳,单相接地故障电弧难以自熄易产生弧光接地过电压及扩大事故,探究弧光接地故障的快速有效熄弧方法是保障配网稳定安全运行的基础。首先根据主动转移型消弧技术的工作原理,建立熄弧过程的等效电路,利用叠加定理推导熄弧时故障点电流计算公式,分析其与故障点位置、接地点过渡电阻、线路负荷电流等因素的关系;然后采用Matlab/Simulink搭建10 kV小电流接地系统单相接地故障模型,其中采用控制论电弧模型模拟单相弧光接地故障;最后通过设置典型的故障点位置、故障点过渡电阻、线路负荷电流作为故障条件,分析不同故障条件及存在高次谐波分量时主动转移消弧过程中的故障点电流、故障点电压波形。分析表明:在单相高阻接地故障时,主动转移消弧技术能够将故障电流转移至站内处理,有效减小故障点电流;在低阻接地故障时,过渡电阻较小导致故障点电流分流较大时,主动转移消弧技术能够限制故障点电压在电弧重燃电压之下;并可有效减小接地故障点的高次谐波分量,从而有效熄弧。The capacitive current of urban low-voltage distribution network in China is rising sharply and the arc extinguishing coil compensation effect is poor. Single-phase grounding fault arc is difficult to self-extinguish, which is easy to generate arc grounding overvoltage and expand the accident. Exploring the fast and effective arc extinguishing method for the arc grounding fault is the basis to ensure the stable and safe operation of the distribution network. Firstly, according to the working principle of active transfer type arc extinguishing technology, the equivalent circuit of arc extinguishing process is established, and the superposition theorem is used to derive the calculation formula of fault point current during arc extinguishing, and analyze the relationship with fault point location, transition resistance of grounding point, line load current and other factors;then Matlab/Simulink is used to build the single-phase ground fault model of 10 kV small current grounding system, in which the cybernetic arc model to simulate single-phase arcing ground fault;finally, by setting typical fault point location, fault point transition resistance, line load current as fault conditions, analyze the fault point current and fault point voltage waveforms in the active transfer arc elimination process when different fault conditions and high harmonic components exist. The analysis shows that: in single-phase high-resistance ground fault, active transfer arc extinguishing technology can transfer the fault current to the station, effectively reducing the fault point current;in low-resistance ground fault, the transition resistance is small resulting in a larger fault point current shunt, active transfer arc extinguishing technology can limit the fault point voltage under the arc reignition voltage;and it can also effectively reduce the high harmonic component of the ground fault point, so as to effectively extinguish the arc.

关 键 词：单相接地故障 主动转移消弧 快速接地开关 故障点电流 熄弧 

分 类 号：TM862[电气工程—高电压与绝缘技术]