电流波形对多柱并联避雷器电流分布的影响

Influence of impulse current waveform on current distribution of multi-column arresters

高压直流输电系统操作过电压持续时间长,释放能量大,为提高避雷器的能量吸收能力,高压直流系统的避雷器多采用多柱阀片并联的结构.多柱并联避雷器柱间电流分配的均匀性对整只避雷器的总体能量吸收能力具有重要影响.为更好地探明冲击电流的波形对多柱并联阀片间电流分布的影响,选取2个厂家的避雷器阀片,试验研究了电流波形对4柱并联阀片的电流分布不均匀系数的影响,研究表明冲击电流的波形对电流不均匀系数具有一定的影响,但影响程度较小,由冲击电流的波形所引起的电流不均匀系数不会超过标准规定值.

The operation overvoltage of high voltage direct current (HVDC) transmission system usually has long duration time and releases a large amount of energy. In order to improve the energy absorption capacity, the multi-column valve structure arrester is adopted. The uniformity of current distribution between columns has an important effect on the total energy absorption capacity of the whole arrester. To investigate the influence of impulse current waveform on current distribution, arresters from two manufacturers are tested in this paper. The results show that the impulse current waveform has some influence on current distribution, but its influence degree is small, the current nonuniformity coefficient caused by the impulse current waveform will not exceed the standard specification.