Motion Characteristics of Copper Particles in Oil Immersed Transformer Insulating Oil and its Effect on Insulation Performance

Abstract

Oil-immersed transformers a key equipment in the power system, their safe and stable operation of the entire power system has an important impact. Oil-immersed transformers generate metal particles during production and transport, which can trigger insulation accidents in the transformer. In this paper, the motion distribution characteristics of copper particles in insulating oil and the influence mechanism on oil insulation performance are studied. The observation platform of impurity motion in oil is set up and combined with the relevant finite element simulation calculations, to carry out the influence of the external electric field environment on the kinetic behavior of solid particles, and to combine with the distribution characteristics of the particles to analyze the influence of their properties on the breakdown characteristics of the insulating oil. The results show that the metal particles will be aligned to form small bridges of metal impurities under the action of the applied electric field, and the increase of the electric field strength will lead to a significant increase in the aggregation of the metal particles. The formation of small bridges of impurities makes the transformer oil conductivity further enhanced, breakdown voltage decreases with the increase of particulate concentration, the results of this paper are of great engineering significance for the fault prevention and safety performance enhancement of oil-immersed transformers.

Keywords

• electrical engineering
• copper
• power transformers
• insulation testing
• impurities