振動性インパルス電圧に対するSF₆中くさびギャップにおける部分放電特性

抄録

It has been reported that there exists a significant difference between the AC and impulse partial discharge characteristics of a wedge gap in SF₆ gas. To clarify this, the partial discharge characteristics against polarity-reversing oscillating impulse voltages with relatively high frequency of 5.4 to 154kHz have been studied. At low gas pressures, the partial discharge inception voltage (PDIV) is almost independent of the frequency and attenuation factor of the applied oscillating voltage, and shows fairly good agreement with PDIV of lightning impulses. On the contrary, at high gas pressures, the PDIV becomes lower as the attenuation factor decreases than the value of lightning impulses and the calculated breakdown voltage of SF₆ gas. It is considered that residual charges remained in the wedge gap are responsible for these phenomena.