Space Charge Behavior in Oil-Impregnated Insulation Paper Reinforced with Nano-TiO2

Abstract

Oil-impregnated insulation paper is widely used in power transformers, and the insulation properties of oil-impregnated insulation paper play an important role in the reliability of power equipment. The formation and dynamics of space charge can affect the performance of insulation material. However, methods to improve the space charge distribution in oil-impregnated insulation paper are rarely reported. In this paper, space charge behavior in oil-impregnated insulation paper has been investigated using the pulsed electro-acoustic (PEA) technique. A series of measurements was applied when the oil-impregnated insulation paper reinforced with different nano-TiO2 contents was subjected to various electric field strengths. The accumulation and decay of space charge are discussed, and the internal electric field strength distribution of oil-impregnated insulation paper is analyzed. The test results show that the space charge distribution is improved and the distortion rate of the internal electric field strength is reduced by adding nano-TiO2 to the oil-impregnated insulation paper. The results show that the proposed method offers a new way to improve the properties of oil-impregnated insulation paper.