覆冰绝缘子交直流闪络场路模型的研究

该文建立了覆冰绝缘子的交直流闪络场路模型，该模型将覆冰绝缘子的闪络分为空气间隙击穿前电弧的起始、空气间隙击穿后电弧在冰表面的发展和临界闪络判定3个阶段。通过对空气间隙击穿前后覆冰绝缘子电场分布的计算，并结合覆冰绝缘子闪络电路模型中电弧的E-I特性和U-I特性，求取覆冰绝缘子的临界闪络电压和电流，进而求取闪络过程中的U-I特性和I-t特性，并可以避免用电路模型采用简化公式计算覆冰各参量所产生的误差。通过与其他理论模型计算结果和真实覆冰绝缘子的试验结果的比较，对该文所建立模型进行了验证。

Reasearch on DC and AC flashover field-circuit model of ice-covered HV insulator

A field-circuit model has been developed to predict the flashover voltage of ice-covered HV insulator, under ac and dc voltage. The flashover process simulation of ice-covered insulator is divided into three stages as arc initiation before air gap breakdown, arc propagation after air gap breakdown and critical flashover determination. Based on the electric field calculation along ice-covered insulator before and after air gap breakdown, and the arc E-I and U-I characteristics, the critical flashover voltage and current can be obtained by the presented model. Moreover, the U-I and I-t characteristics can be determined by this model, which can avoid the errors caused by the simplified calculation methods on icing parameters in the circuit model. The results obtained from the presented field-circuit model have been compared with other theoretical and experimental results, which validates the presented field-circuit model.