Open AccessPartial discharge characteristics of an air gap defect in the epoxy resin of a saturable reactor under an exponential decay pulse voltage
Author(s) -
Gui Lu,
Mi Yan,
Deng Shengchu,
Liu Lulu,
Ge Xin,
Ouyang Wenmin
Publication year - 2020
Publication title -
high voltage
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.732
H-Index - 20
ISSN - 2397-7264
DOI - 10.1049/hve.2019.0121
Subject(s) - voltage , materials science , pulse (music) , exponential decay , space charge , exponential function , amplitude , partial discharge , rise time , atomic physics , physics , electrical engineering , optics , mathematics , electron , mathematical analysis , nuclear physics , engineering
Saturable reactor insulation is currently stressed by an exponential decay pulse voltage under normal operating conditions. The partial discharge (PD) characteristics of epoxy resin under an exponential decay pulse voltage were studied here and were compared at 25 and 110°C. In addition, this study compares these PD characteristics with those under a sinusoidal voltage to better measure the insulation design margin of the saturable reactor under an exponential decay pulse voltage. Finally, this study explains the PD mechanism based on the three‐capacitor circuit model and space charge accumulation. Compared with the sinusoidal voltage, a higher amplitude, a higher inception voltage and fewer PDs are obtained under the pulse voltage. The reason may be related to the accumulation of space charge. Due to the duality of the space charge effect, the promotion effect of space charge accumulation on the PD under the pulse voltage is dominant, and an increase in temperature will weaken the promotion effect. In contrast, the inhibitory effect of space charge accumulation on the PD under the sinusoidal voltage is dominant. The experimental results can provide a basis for the optimal design of saturable reactor insulation under an exponential decay pulse voltage.