考虑场致发射电流自均压作用的串联多真空间隙击穿概率预测方法OA

Breakdown(BD)voltage of multiple vacuum gaps(VGs)in series shows significant randomness.Accurate prediction of its BD probability distribution is crucial for the quantitative design of the insulation structure in high-voltage vacuum interrupters.This article proposes a prediction method for the BD probability of multiple VGs in series under a lightning impulse voltage(LIV),taking into account the self-voltage sharing effect of the field emission current.The pre-BD characteristics of multiple VGs were quantitatively studied by establishing an equivalent circuit,and the self-voltage sharing effect of field emission current was clarified.Further,the static voltage distribution of multiple VGs was corrected by the obtained field emission influence coefficient,and the distribution under the sharing effect was determined.On these bases,combining with the BD probability Weibull function of each single VG,the prediction of BD probability distribution for multiple VGs was achieved.Validated by experiments,for double and triple sphere-plane VGs,the prediction error of BD probability distribution considering the self-voltage sharing effect was approximately 5％,which was reduced by nearly 15％compared to the method without consideration.The problem that the previous methods seriously underestimated the upper limit of voltage endurance capability for multiple VGs was effectively solved.