Revisiting the Feasibility of Distinguishing the Long-Term Stability of MOVs by Power Loss

Power loss transition of stable ZnO varistor ceramics: Role of oxygen adsorption on the stability of interface states at the grain boundary

“…where A * =30 A cm -2 K -2 is the effective Richard constant, q is the elementary charge, ξb = 0.067 eV is the bulk Fermi level relative to the conduction band, k is the Boltzmann constant, T is the absolute temperature, and U is the applied voltage. According to the DIR model [25,26], the power loss trend is the result of competition between donor ion redistribution and the consumption of the interface states.…”

“…Electrical parameters of α, Eb, and JL show rapid recovery in the first 2 h, and subsequently approach their unaged values at 509 h. The recovery thereby indicates the existence of stable interface states in stable ZnO varistor ceramics. The minor variations in J-E curves and electrical parameters result from the donor redistribution effect in depletion layers [25,26].…”

“…However, the aging of stable ZnO varistor ceramics cannot be explained by this classic model. Facing this challenge, we recently proposed a donor ion redistribution (DIR) model and simulated the carrier transport in a DSB by including the effect of donor redistribution with stable interface states at GBs [25,26]. The decreasing power loss and evolution of J-E characteristics of stable samples were theoretically reproduced during the aging.…”