In　order　to　further　apply　SF6/N2in　power　equipment,　we　studied　the　breakdown　characteristics　of　SF6/N2in　different　electric　field　non-uniformity　via　fully　enclosed　power　frequency　experimental　apparatus,　and　studied　the　characteristics　of　partial　discharge　inception　voltage　in　non-uniform　electric　field.　The　research　indicates　that　the　breakdown　voltage　of　SF6/N2gas　mixtures　increases　linearly　with　increase　of　gas　pressure　in　slightly　non-uniform　electric　field.　With　increase　of　the　electric　field　non-uniformity,　the　saturated　trend　of　breakdown　voltage　appears.　When　electric　field　non-uniformity　exceeds　a　certain　value,　the　stable　corona　discharge　appears　before　the　electric　breakdown　of　electrodes　gap.　The　N-curve　characteristic　of　breakdown　voltage　appears　in　SF6and　its　mixtures.　With　the　increase　of　electric　field　non-uniformity,　the　amplitude　and　range　of　N-curve　extend.　With　the　increase　of　electric　field　non-uniformity,　the　synergistic　effect　becomes　more　significant　and　then　is　weakened.　The　significant　phenomenon　of　critical　radius　can　be　found　in　pure　N2,　and　the　critical　radius　is　around　1　mm　to　2　mm.　However,　the　phenomenon　is　not　obvious　in　gas　mixture　and　pure　SF6,　and　with　the　decrease　of　the　electrode　radius　of　curvature,　the　breakdown　voltage　decreases　obviously　under　high　pressure,　while　it　increases　under　low　pressures.　©　2017,　High　Voltage　Engineering　Editorial　Department　of　CEPRI.　All　right　reserved.