Impulse Aging Behavior of ZnO-V2O5-Based Varistors withNb2O5 Addition

Abstract

The effect of Nb2O5 addition on impulse aging behavior of ZnO–V2O5–MnO2–Co3O4–Dy2O3-based varistors was investigated. The varistors doped with 0.25 mol% Nb2O5 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% Nb2O5 exhibited the best electrical stability by marking %ΔE1 mA=−1.0%, %Δα=−2.8%, and %ΔJL=31.5% after applying the impulse current of 100 A.