Dynamic features of DC flashover on polluted insulators

Theoretical and experimental investigation of AC and DC arc propagation on polluted insulators surface

“…However, extensive experimental research shows that the critical current varies from 200 to 450 mA, up to 1 A, which is dependent on the pollution layer resistance and insulator profile. Many researchers developed the ionization or breakdown explanation with current over 200 mA for DC and AC [13][14][15]. In References [15][16][17], it was proposed a discharge mechanism close to the leader breakdown, where the ionization process of the arc stem plays an important role for the discharge guiding for low and high current (<1 A).…”

“…This ionization is thought to extend the arc to flashover. The ionization or breakdown explanation with current over 200 mA for DC and AC is developed [13][14][15]. In [15][16][17], a discharge mechanism close to the leader breakdown is proposed, where the ionization process of stem plays an important role in the discharge guiding for low and high current (<1 A).…”

DC flashover criterion and discharge elongation mechanism in an air–electrolyte interval

“…At this instant, the initial discharge between HV rod electrode and the centre of the vat (Fig. 4) is considered to have a tubular form of uniform diameter [31], unlike its elongated form where it has an extended foot with its forefoot propagating during discharge elongation [23].…”

“…Unfortunately, the proposed criteria and mechanisms are not yet confirmed, and the disagreement between the various hypotheses remains a subject for discussion [22, 23].…”

Electro‐thermal dynamic model using the analytical arc parameters for the prediction of the critical flashover condition on the HVDC polluted insulator

“…leakage current, arc temperature, elongation, arc resistance and pollution resistance) are mostly been covered by dynamic models proposed to better explain/clarify the arc propagation process. Thus, much works have been reported in the literature to describe the flashover dynamic that happen in polluted insulators, in which each author propose/design its proper model to describe this phenomenon [1, 10,15,28]. Rizk and Nguyen [9] were among the first researchers in this area that propose modelling the DC flashover dynamic.…”