Research on controlled switching in reducing unloaded power transformer inrush current considering circuit breaker's prestrike characteristics

Experimental Investigation of the Prestrike Characteristics of a Double-Break Vacuum Circuit Breaker under DC Voltages

“…During the making process of the VCB, there is a threshold electric field strength that determined whether breakdown occurs or not [32]. When the electric field strength exceeds the threshold electric field strength between the contacts, the prestrike arc occurs and the gap between the contacts at that instant is called prestrike gap, which is independent of the initial gap of the VCB [33]. However, if there is an inrush current in the prestrike process that causes erosion on contacts or the prestrike gaps are larger than 2 mm, the initial gap of the single-break VCB and the double-break VCB must be kept the same in order to compare the characteristics of prestrike gaps.…”

Insulation risk assessment of controlled switching considering pre‐strike voltage and line trapped charge

“…6 that at instants before crossing zero, a pre-closing or pre-strike voltage has been created because of the decrease in dielectric withstand of the gap between the contacts. In the beginning, for the sake of simplicity, it is assumed that the line trapped charge is zero [26]. In this paper, this issue has been generalised to a case in which the trapped charge exists in the line side.…”

Estimation of switching surge flashover rate of point on wave switching over‐voltages along transmission line by adaptive neuro‐fuzzy inference system meta‐model

“…Many studies [6–10] present point on wave switching (PWS) without considering LTC. In one of the most impressive study, [6], a PWS strategy is proposed in which there exists an imprecision since the closing instant is determined only by LTC polarities.…”