In order to obtain high performance ZnO varistors

the electrical properties of zinc oxide varistors co-doped with aluminum and gallium ions were investigated. The volt-ampere characteristic curves of zinc oxide varistors in small current region and high field region were examined. At a fixed alumina doping concentration

with the increase of gallium doping concentration

the voltage gradient and non-linear coefficient of zinc oxide varistor show a trend of first rising and then decreasing. In addition

leakage current shows a trend of first decrease and then increase. When the doping concentration of aluminum is 0.1% and the doping concentration of gallium oxide is 0.72%

the zinc oxide varistor presents the best electrical performance. At this time

the varistor shows low residual voltage

high non-linear coefficient and low leakage current. This research will help to assemble zinc oxide varistors with excellent electrical properties in the power system.