高压限流熔断器的电弧特性决定了其分断过电压和分断能力。为研究这一电弧特性,在分析燃弧过程物理原理的基础上,建立了半经验式的限流熔断器电弧模型。模型考虑了熔体烧蚀、电弧通道截面积扩展、电弧电场强度、电弧极区电压降及电弧融合等必要的物理过程,对每个过程的计算主要采用经验公式。通过多次短路分断试验对模型进行检验,结果表明计算和试验具有较好的一致性。以XRNT1.12/200-50型高压限流熔断器为例,应用该模型对不同结构参数下的电弧特性进行了计算分析,讨论了过电压和燃弧能量随参数变化的规律,给出了使过电压和燃弧能量都能满足要求的设计方法。
The breaking overvoltage and breaking capacity of a high voltage current limiting fuse (HVCLF) are greatly related to its arcing characteristics. By analyzing the physical principle of arcing process in HVCLF, we proposed a semiempirical arcing model of CLF. The model takes many essential physic progress of arcing into consideration, in cluding the burnback of fuselink, expansion of arc channel crosssectional area, arc electric field intensity, voltage drop across the polar region, and arc fusion. Meanwhile, the details of these basic physics processes were calculated by empir ical formulas. Several short circuit breaking tests were designed to verify this model, and the results indicated certain consistence between experiments and calculations. Moreover, taking XRNT112/20050 HVCLF as an example, we ap plied the model to calculate its arcing characteristics under different structural parameters and discussed the patterns of overvoltage and arcing energy with different paraeters. A design meeting the requirements of HVCLF in both overvoltale and arcin enerrv was also orooosed.