Impulse Aging Behavior of ZnO-V_2O_5-Based Varistors with Nb_2O_5 Addition

摘要

The effect of Nb_2O_5 addition on impulse aging behavior of ZnO-V_2O_5-MnO_2-Co_3O_4-Dy2O_3-based varistors was investigated. The varistors doped with 0.25 mol% Nb_2O_5 exhibited the best clamp characteristics, in which the clamp voltage ratio was in the range of K= 1.65-2.50 at an impulse current of 1-50 A. The varistors doped with 0.1 mol% Nb_2O_s exhibited the best electrical stability by marking %△E_(1 mA)=-1.0%, %△a = -2.8%, and %△J_L = 31.5% after applying the impulse current of 100 A.