颗粒污染物对变压器油击穿电压的影响

Effect of Particulate Contamination on Breakdown Voltage of Transformer Oil

变压器油中存在的固体颗粒物极易劣化油液的理化性能,尤其是金属颗粒对绝缘性能的影响更为显著。根据ISO4406标准,采用均匀设计法,配制了24组含Cu、Fe、SiO2的不同粒径不同污染度的颗粒污染物油样并对其进行了击穿电压性能测试,获得了不同组分、颗粒含量对油液击穿电压的影响规律;根据测试数据建立了油样中不同粒径、含量的颗粒物与油样击穿电压之间的支持向量机数学模型。结果表明实验验证集利用所建模型获得的决定系数为0.9551、均方根误差为0.181×10^-2;随着Cu、Fe、SiO2颗粒含量的增加,油液的击穿电压减小;颗粒污染物在5-25μm范围内对油液击穿电压影响较为显著,且粒径越大,油液击穿电压值也越大。

There are the physical and chemical properties which transformer oil is easily deteriorated by the solid particles in oil, especially the influences of metal particles on the insulation performance of oil is more significant. Based on the ISO4406 standard, we prepared 24 groups of oil samples with different particle sizes and different pollution degree of Cu, Fe, and SiO2 by a uniform design method. Moreover, we obtained the influence law of different component and particle content on the breakdown voltage of oil according to the test performance of breakdown voltage. According to the test data, we established a mathematical model of support vector machine between particles with different particle size, particle content and breakdown voltage of oil samples. The results show that the determination coefficient is 0.9551 and the root mean square error is 0.181×10^-2 of the validation set using the model; With the increase of the content of Cu, Fe, and SiO2 particles, the breakdown voltage of oil is decreased; The contamination of particles in the range of 5-25 μm has a significant influence on the breakdown voltage of oil, and the bigger the particle diameter is, the greater the breakdown voltage of oil will be.