Research on Power Frequency Breakdown Characteristics of Nitrogen-Polymer Barrier
The use of nitrogen(N2)with appropriate pressure as the alternative gas for SF6 is currently a research hotspot for medium-voltage environmentally friendly switchgear.The introduction of a barrier and its gas-solid com-posite insulation gap in nitrogen can better improve the withstand voltage.In this paper,by changing the horizontal position,vertical size,material and electrode structure of the barrier,the variation law of breakdown voltage in nitro-gen under different conditions is obtained.At the same time,the breakdown path is analyzed in segments,the types and probabilities of each breakdown path are summarized,and finally the electric field distribution changes on the breakdown path are analyzed in combination with simulation.The results show that the breakdown voltage in nitro-gen within a certain open distance changes more regularly with the distance of the electrode than that of air.The closer the barrier is to the high-voltage electrode and the larger the vertical size of the separator,the higher the breakdown voltage.Among the separators of the three materials,polytetrafluoroethylene(PTFE)plate has the weakest effect on the breakdown voltage,and mica plate has the best effect on breakdown voltage,but its breakdown voltage is significantly affected by the horizontal position.The difference in breakdown voltage at different horizontal posi-tions is due to the different distribution of electric fields.The breakdown voltage has little to do with the breakdown path,and the vertical size is an important factor affecting the type of breakdown path.The research results can pro-vide a reference for the design and optimization of composite insulation between nitrogen and polymer barriers.
nitrogen gashybrid gas-solid insulationbreakdown pathelectric field distribution
万方数据
维普
