Effect of electron shallow trap on breakdown performance of transformer oil-based nanofluids

作者：Yuefan Du, Yuzhen Lv, Chengrong Li, Mutian Chen, Jianquan Zhou, Xiaoxin Li, You Zhou, Youping Tu · 发表于：Journal of Applied Physics · 年份：2011 · DOI：10.1063/1.3660783 · 被引用次数：211 · 研究领域：High voltage insulation and dielectric phenomena、Power Transformer Diagnostics and Insulation、Lightning and Electromagnetic Phenomena

Transformer oil-based nanofluids with TiO2 semiconductive nanoparticles exhibit substantially higher AC and positive impulse breakdown voltage levels than that of pure transformer oils. Thermally stimulated current method (TSC) and pulse electroacoustic technique (PEA) have been used to measure charge trap and transportation characteristics of pure oils and nanofluids. It is found that electron shallow trap density and charge decay rate are greatly increased in nanofluids, i.e., fast electrons may be converted to slow electrons by electron trapping and de-trapping in shallow traps of nanofluids, resulting in improved breakdown performance compared to that of pure oil.