The Study on TiO<sub>2</sub> Nano-Powder’s Influence on the Power Frequency Breakdown Properties of Transformer Oil

Abstract

There are plenty of intrinsic cation states on the surface of nano-semiconductor crystals. When the crystals contact the transformer oil，surface states that can capture electrons easily are formed. In this paper, TiO2 nano-powders with different surface modifications have been used to improve the property of transformer oil (Karamay 25#). The modification effects of nano-power’s on insulating property of transformer oils have been investigated. And the modifying effects of TiO2 nano-powder with different concentrations on transformer oil have been studied. The breakdown property tests and fitting results show that TiO2 nano-powder can improve the breakdown properties of transformer oil and within some concentrations，the higher the concentration of TiO2 nano-powder，the better the power frequency insulating property of modifying transformer oil. Besides，The modifying agents play a key role in the dispensability of TiO2 nano-powder in the transformer oil. With the increasing of nonpolar segment in the modifying agent, the breakdown property of the modified oils gets more enhancements.