Study on the Breakdown Characteristics of Multiple-Reignition Secondary Arcs on EHV/UHV Transmission Lines

• Published in: IEEE transactions on plasma science 2023-04, Vol.51 (4), p.1-9
• Main Authors: Li, Runchang, Liu, Hongshun, Lou, Xiaoxuan, Song, Ping, Hou, Weihong, Dai, Shiqiang, Shi, Yuchao, Jin, Gongyu, Siew, Wah Hoon, Li, Qingmin
• Format: Article
• Language: English
• Subjects: Air gaps; Arc breakdown; Breakdown; Breakdown voltage; Circuit faults; Dielectric strength; Electric breakdown; Electric potential; Extinction; extinction theory; Ignition; multiple reignition; Power supplies; Power system stability; Power transmission lines; secondary arc; Short circuits; single-phase-to-ground fault; Transient analysis; Transmission lines; Voltage; Wind direction; Wind speed
• ISSN: 0093-3813; 1939-9375
• DOI: 10.1109/TPS.2023.3252799

A long-gap ac arc with a length of more than 10 m (secondary arc) is normally generated at the short-circuit arc channel after a single-phase-to-ground fault. In previous studies, arc breakdowns of secondary arcs have mainly been considered as electrical breakdowns, ignoring the role of heat in the arc channel. Besides, the extinction-reignition theory of secondary arc, i.e., dielectric strength recovery theory, still lacks the support of experimental data. In this study, based on the equivalent experiments performed in the laboratory, the influences of compensation degree of transmission lines, initial recovery voltage gradient of air gap, test current, wind speed, and wind direction on the breakdown characteristics of secondary arcs are studied and statistically analyzed. The laws of the transient recovery voltage (TRV) and of the rate of rise of recovery voltage (RRRV) are also studied by considering the influencing factors mentioned above. The results of this study will provide a more complete experimental basis for the theory of extinction-reignition of secondary arcs and a deeper understanding of the transient characteristics of arc breakdown.