Research on detection technology of bubble size distribution in transformer oil based on MIE scattering theeory

The existence of bubbles in oil paper insulation will seriously reduce its insulation strength, and the particle size of bubbles is one of the key parameters affecting its insulation performance. In the field of electrical engineering, there is no method to detect the particle size of bubbles in transformer oil. In this paper, a method for detecting bubble size in oil is proposed based on Mie scattering theory. The spatial distribution of scattered light intensity contains the particle size information of bubbles, and then the particle size distribution law of bubbles is deduced. Firstly, an experimental platform for bubble detection was built, and then the inversion algorithm was written by using relevant theoretical calculation. Silicon carbide particles with known particle size were used as calibration samples, and the particle size distribution of cavitation bubbles due to vibration was also detected. The calibration and actual detection results show that this method can be used to detect bubbles in transformer oil.