Measurement and influence factor analysis of ion mobility of vegetable insulation oil

The vegetable insulation oil has been widely used in distribution transformers and extended to high voltage power transformers. In order to make the vegetable insulation oil well used in the HVDC applications, it is necessary to study the ion mobility of vegetable insulation oil under different influencing factors. In this paper, we measured the ion mobility of insulation oil using the reversal polarity method, and discussed the influences of voltage amplitude on the measurement results. The properties of ion mobility for vegetable insulation oil were measured at different temperatures and we also measured the ion mobility of the different moisture content in vegetable insulation oil. The results show that the obtained mobility values are independent of the voltage level, when the measurements were performed at low test voltages. The ion mobility of vegetable insulation oil increase with the rising temperature, which satisfies the Arrhenius relationship with the reciprocal of temperature. The moisture content of vegetable insulation oil has some impact on the positive ion mobility.