Electrothermal characterization of HVIC under bipolar DC in concurrent extended stressing and dry band arcing

Ullah, Israr, Ullah, Rahmat, Bashir, Muhammad Mehran, Giangrande, Paolo, Madonna, Vincenzo, Ji, Yatai and Galea, Michael 2026. Electrothermal characterization of HVIC under bipolar DC in concurrent extended stressing and dry band arcing. IEEE Transactions on Dielectrics and Electrical Insulation 10.1109/tdei.2026.3656867

Full text not available from this repository.

Abstract

Room temperature vulcanized silicone rubber (RTV-SiR) is broadly recommended as a high voltage insulator coating (HVIC) for ceramic insulators in polluted zones. However, the rising HVDC ranges impose serious challenges in terms of coating degradation. To increase the acceptability of HVIC, the present work investigates the electrothermal characteristics of RTV-SiR for HVIC using the inclined plane test in conjunction with long-term accelerated aging. Four types of RTV-SiR composites are fabricated by adding various wt% of micro, nano, and micro-nano (hybrid) silica fillers. Inclined plane tests (IPT) are conducted separately for both polarities of DC on pristine and aged samples (treated with accelerated multi-stressing in the lab for 10,000 hours). Unaged hybrid samples (SB4) outperform by achieving the highest initial tracking voltage (ITV) of 3.25 kV for negative polarity DC (–DC) IPT, followed by the counterpart under positive polarity DC (+DC). Similarly, a notable suppression of leakage currents is witnessed in hybrid and 20 wt% silica-added composites throughout the IPT campaign. Also, from time to failure analysis, a relatively shortened time to failure is observed for all blends treated under positive DC, confirming the detrimental impact of positive polarity. For instance, unaged pure SiR samples (SB1) feature 6 hours before failure under –DC stress compared to 5 hours when +DC is applied. From the findings, it is recognizable that hybrid composites depict better overall performance, followed by samples with 20 wt% filler, thus showing high integrity under all test conditions.

Item Type:	Article
Date Type:	Published Online
Status:	In Press
Schools:	Schools > Engineering
Publisher:	Institute of Electrical and Electronics Engineers
ISSN:	1070-9878
Last Modified:	26 Jan 2026 15:30
URI:	https://orca.cardiff.ac.uk/id/eprint/184206

Actions (repository staff only)

Edit Item