Simulation of Surface Discharge Based on the Different Ratio of Dielectric Constants of Oil and Papers
Chen Gang1, Huang Zhengyong1, Duan Yu1, Li Jian1, Yao Degui2
1. State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing 400044 China; 2. State Grid He'nan Electric Power Corporation Electric Power Research Institute Zhengzhou 450052 China
Abstract Oil-paper insulation system is an essential part of transformer insulation, and oil-paper surface discharge is one of the main causes of transformer failure. In this paper, the mathematical model and multi-physical field simulation model of oil-paper discharge were constructed by Gauss and current continuity equations. The discharge characteristics when the paperboard respectively parallel and perpendicular to the electric field direction in different oil / paper dielectric constant ratio systems under positive lightning impulse voltage were studied. The electric field and space charge distribution characteristics in pure oil and the oil with pressboard existed were analyzed. The influence of different oil/paper dielectric constant ratios on the streamer propagation path was analyzed. The results show that the oil/paper dielectric constant ratio directly affects the development morphology of the streamer. The higher the difference, the easier the streamer grows along the pressboard surface and the more uneven distribution of the electric field. This research has important guiding significance for the design and material selection of the oil-paper insulation system.
Chen Gang,Huang Zhengyong,Duan Yu等. Simulation of Surface Discharge Based on the Different Ratio of Dielectric Constants of Oil and Papers[J]. Transactions of China Electrotechnical Society, 2020, 35(zk2): 620-628.
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2020, Vol. 35 
