特快速暂态过电压下避雷器模型的研究与应用

目前,由于多种因素,金属氧化物避雷器在抑制特快速暂态过电压(VFTO)方面的应用有限。为了满足VFTO下避雷器的动态特性的需求,笔者介绍一种适用于VFTO计算的避雷器模型,由于避雷器电容效应,造成高频下残压和放电电流之间存在时间延迟,导致避雷器响应速度变慢。结合实例,对采用文中建议的模型和IEEE建议的模型下的VFTO做了仿真分析。结果表明:改进的Micaela避雷器模型在冲击电流波前时间<1μs具有较好的动态特性及精度,适用于VFTO的研究。

Application and Research on Surge Arrester Models under Very Fast Transient Overvoltage

Presently,metal-oxide arresters find very limited applications in suspression very-fast transient overvoltage(VFTO).In order to meet the needs of the dynamic performance of arrester under VFTO,a surge arrester model applied to very fast transient overvoltage is proposed in this paper,and there is a time lag between the residual voltage and discharge current under high frequency due to MOA capacitance effects,and.resulting in a slow response of the arrester.Combined with the example,the research on VFTO for the proposed model and the model proposed by IEEE has been done.The results show that:when the impulse current wave front time<1μs,the improved MOA model has better dynamic characteristics and accuracy,and is applied to very fast transient overvoltage(VFTO) research.