中文摘要：

利用振荡回路在杯状纵磁灭弧室中产生频率400Hz的中频真空电弧，在开距为3mm的条件下，选取触头材料为纯Cu、Cu-W-WC合金和CuCr50合金，直径为41mm和58mm的灭弧室进行不同电流等级的实验，对比分析电弧电压和电弧形态的变化。实验结果表明：中频真空电弧的特性和真空灭弧室的开断性能，与触头材料和直径有密切的关系；对直径相同的触头，CuCr50合金触头的开断能力强于纯Cu和Cu-W-WC合金；随着触头直径的增大，电弧电压减小，电弧扩散均匀且更稳定，灭弧室的开断能力更强。

英文摘要：

The oscillating circuit was utilized to generate 400Hz intermediate-frequency vacuum arc in the cup-type interrupter with axial magnetic field （AMF）. In the condition of the 3mm opening gap, experiments of different currents were carried out in interrupters with the contact materials being Cu, Cu-W-WC alloy and CuCr50 alloy and with the diameters being 41mm and 58mm respectively. The arc voltage and the transformation of arc performances were analyzed contrastively. The experiment results indicate that the contact material and diameter are closely related to the breaking capacity of the vacuum interrupter and characteristics of intermediate- frequency vacuum arc. For contacts of the same diameter, the breaking capacity in CuCr50 is better than that in Cu and Cu-W-WC. With the contact diameter increasing, the arc voltage gradually decreases, and the diffuse arc tends to be stable, for which the breaking capacity is better.