An electrostatic approach for the calculation of breakdown voltage for quasi-homogeneous sphere-plane gaps

Influences of surface tips of a shield ball on the discharge characteristics of a long sphere‐plane air gap under positive switching impulses

“…The maximum difference of U 50% under three lengths of burrs was 572 kV, which decreased by 30.4% compared with 1833 kV. Similarly, under 3 and 7 m of gap spacing, the maximum difference of U 50% also reached to 39.1 and 24.8% of the discharge voltages in a smooth surface condition under corresponding gap distance [14,15]. This indicated that the burrs on the surface of the shield ball all significantly decreased the discharge voltage of the sphere-plane air gap under the three gap distance, and the influence degrees all surpassed 20%, showing a significant burr effect.…”

Influence of protrusions on the positive switching impulse breakdown voltage of sphere‐plane air gaps in high‐altitude areas

“…It was pointed out in previous research [19][20][21] that it is inevitable that there are defects such as burrs and pits on the surface of the shield balls in the valve hall, which affect air gap discharge characteristics. Existing research [22][23][24] also simulated the electrical field intensity in the presence of tiny defects on shield balls and conducted switching impulse discharge tests thereon. The results show that the surface defects of the electrode will reduce the air gap breakdown voltage, and the test results have certain guiding significance.…”

Electrostatic field features on the shortest interelectrode path and a SVR model for breakdown voltage prediction of rod–plane air gaps

“…If we can establish the relationships between the static electric field and the breakdown voltage directly, it may be possible to accurately predict the dielectric strength of air insulation, without detailed consideration of the complex and random discharge process. For electrostatic field analysis of air gaps, the maximum field strength at the electrode tip is the most concerned results [12]. However, the breakdown conditions of different gap arrangements are not only determined by the maximum field strength [13], the distribution characteristics in the interelectrode gap should also be considered.…”