Aging characteristics of ZnO–PrO1.83-based semiconducting varistors for surge protection reliability

Abstract

This research focuses on the aging characteristics of Er2O3-doped ZnO–PrO1.83-based varistors for surge protection reliability. The MOV (metal oxide varistor) doped with 2.0mol% exhibited the best clamp characteristics, in which the clamp voltage ratio was in the range of K=1.56–1.84 for surge current of 5–50A and K=1.92–3.13 for surge currents of 400–1800A. On considering surge absorption capability, the MOV doped with 0.5mol% Er2O3 exhibited a very strong electrical stability, with %ΔE1mA/cm2 and %Δα1 less than 5% for the multi-surge current of 2100A, whereas the MOV doped with 2.0mol% Er2O3 was destroyed at the same condition.