SF_(6)断路器灭弧室内短路电流开断过程仿真研究  

Simulation Study on Interruption Process of Short-circuit Current in SF_(6) Circuit Breaker Chamber

作　　者：王佳琳 周雄 彭彦军 张晓辉 黄勇强 WANG Jialin;ZHOU Xiong;PENG Yanjun;ZHANG Xiaohui;HUANG Yongqiang(Guangxi Power Grid Co.,Ltd.,Nanning,Guangxi 530023,China;Guilin Power Supply Bureau of Guangxi Power Grid Co.,Ltd.,Guilin,Guangxi 541002,China)

机构地区：[1]广西电网有限责任公司,广西南宁530023 [2]广西电网有限责任公司桂林供电局,广西桂林541002

出　　处：《广东电力》2022年第11期72-80,共9页Guangdong Electric Power

基　　金：广西电网有限责任公司科技项目(0403002020030103BY00067)。

摘　　要：SF_(6)断路器灭弧室为封闭式结构,难以直接观测到开断过程灭弧室内各物理场的变化情况,为此建立灭弧室内开断过程的电热流体多物理场耦合仿真模型,研究开断过程中各物理场的变化规律。研究发现:当电流在开距较小时过零易导致电弧重燃,电弧的熄灭必须具备足够的吹弧气流速度与介质恢复强度;在开断30 kA短路电流时,电弧最高温度约18000 K,熄弧后弧隙温度迅速降低到3000 K以下;压气缸内气体压力随触头运动逐渐增大,最大可达1.0 MPa;吹弧气体速度随喷口的打开逐渐增大,最大速度为253 m/s,冷态气体会带走大量电弧能量并不断压缩电弧半径,为电流过零创造有利的熄弧条件;弧隙最大电场强度随间隙距离与电压变化,一般出现在静弧触头端部与动弧触头弧角处。研究结果可为SF_(6)断路器短路开断过程与机理分析提供理论支撑。Since the arc extinguishing chamber of SF_(6) circuit breaker is a closed structure,it is difficult to observe the changes of physical fields in the arc extinguishing chamber during the process of breaking short circuit current.Therefore,this paper establishes a multi-physical field coupling simulation model of the breaking process in the arc extinguishing chamber to study the change laws of various physical fields including electricity,heat and fluid in the breaking process.The results show that when the current is small,zero crossing easily leads to reignition of the arc,and the arc extinguishing must have sufficient airflow velocity and medium recovery strength.When the short-circuit current of 30 kA is broken,the highest temperature of the arc plasma is about 18000 K,and the gap temperature rapidly decreases to less than 3000 K after arc extinguishes.The gas pressure in the cylinder increases gradually with the movement of the contacts,and the maximum pressure reaches 1.0 MPa.The speed of arc blowing gas increases gradually with the opening of the nozzle,and the maximum speed is 253 m/s.The cold gas takes away a lot of arc energy and compresses the arc radius continuously,which creates favorable conditions for arc extinguishing for the current zero crossing.The maximum electric field intensity of arc gap varies with gap distance and voltage and generally appears at the end of static arc contact and the arc angle of moving arc contact.The research results could provide theoretical support for analyzing short breaking process and mechanism of SF_(6) circuit breaker.

关 键 词：SF_(6)断路器 平衡态等离子体 多物理场耦合仿真 熄弧过程 

分 类 号：TM561.3[电气工程—电器]