阻性隔板液态金属限流器设计与限流特性分析  

Design and Current Limiting Characteristic Analysis of Resistive Wall Liquid Metal Current Limiter

作　　者：段雄英[1] 李金金 谢为赢 黄智慧[1] 廖敏夫[1] Duan Xiongying;Li Jinjin;Xie Weiying;Huang Zhihui;Liao Minfu(School of Electrical Engineering Dalian University of Technology,Dalian 116024 China)

机构地区：[1]大连理工大学电气工程学院,大连116024

出　　处：《电工技术学报》2023年第17期4779-4786,共8页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(52177131);武汉强磁场学科交叉基金(WHMFC202130)资助项目。

摘　　要：液态金属限流器(LMCL)具有独特的优势,在电力系统的限流方面有良好的应用前景。为了减小LMCL烧蚀,提高使用寿命,该文设计了一种阻性隔板液态金属限流器(RWLMCL)。首先,从腔体内部的电流分布角度,分析了RWLMCL减少烧蚀的原因。然后,通过实验与仿真探究了RWLMCL中液态金属自收缩效应的动态变化过程。结果表明,仿真与实验结果具有很好的一致,证明了理论模型的合理性。将LMCL的隔板由绝缘替换为阻性,液态金属自收缩效应仍然有效。最后,比较了RWLMCL与现有绝缘隔板LMCL的限流特性与烧蚀情况,发现与绝缘隔板LMCL对比,铁钴镍隔板LMCL的电流峰值减小了2.68%,电弧电压峰值减小了95.0%,弧前时间减少了23.9%,燃弧时间减少了68.8%,阻性隔板的氧化锌隔板LMCL与铁钴镍隔板LMCL的液态金属烧蚀明显减弱。结果证明,RWLMCL可以限制液态金属电弧剧烈燃烧,减少腔体的烧蚀,从而有效地延长LMCL的使用寿命。Liquid metal current limiter(LMCL)have unique advantages.It has a good application prospect in the current limiting of the power grid.In order to reduce the erosion of LMCL and improve the service life,a resistive wall liquid metal current limiter(RWLMCL)was designed in this paper.During the current limiting process,the resistive wall can be connected to the circuit.First,the reason for the RWLMCL reduced arc intensity was analyzed from the perspective of current distribution inside the cavity.When the wall is the resistive material,the arc resistance and the wall resistance share the short-circuit current.During the burning arc process,the arc resistance increases gradually with the enhancement of the arc,and the wall branch current gradually increases.Compared with the insulating wall LMCL,the current flowing through the arc branch of the RWLMCL is decreased,and the arc intensity is reduced,which can effectively reduce the erosion of the cavity.Further,in order to explore the mechanism of the liquid metal self-pinch effect in the RWLMCL,the liquid metal dynamic change under the action of current was analyzed by experiment and simulation.The liquid metal current density at both ends of the channel will suddenly change because of the RWLMCL channel structure.The liquid metal Lorentz force changes most at the four corners of the grooves and channel.Under the action of Lorentz force and air flow,the liquid metal at the four corners is first depressed.With the increase of the current,the liquid metal Lorentz force in the depressions further increases,so that the depressions continues to deepen and expand.The depressions reach the bottom end of the channel,and the liquid metal paths break.By replacing the insulating wall of the LMCL with a resistive wall,the liquid metal self-pinch effect is still effective.The simulations are in good agreement with the experiment results,which proves the rationality of the theoretical model.Finally,using LC oscillation circuit as power supply,experiments were carried out on three LM

关 键 词：液态金属限流器 隔板材料 液态金属自收缩效应 限流特性 

分 类 号：TM773[电气工程—电力系统及自动化]