Exploration of the Relationship Between Tyndall Effect and Moisture Content in Transformer Oil

Moisture content in oil detection technology such as offline method and online monitoring method has several shortcomings. In this article, the Tyndall effect of moisture content in transformer oil was excited by a laser with a wavelength of 633 nm, and the relationship between Tyndall effect and moisture content in transformer oil was investigated. The relationship between the grayscale of laser beam column and particles in oil and the relationship between the grayscale of laser beam column and temperature are also investigated. It was found that withstand voltage of the oil was negatively correlated with the gray pixel statistics of the light column, while the micro water content was positively correlated with the pixel statistics of the light column. The attenuation of the light column is only related to particle size. When the micro water content is below 10 ppm, the light column will have a significant brightening process with the increase in temperature, but it will gradually slow down above 10 ppm. The statistical value of gray pixels and the proportion of gray intervals can be used for moisture content determination. This method provides a new direction for the insulation performance detection technology of transformer oil.