DC metal oxide varistors are modified on the basic recipe toadapt to the DC voltage withstand characteristics and aging characteristics, ithas the advantages of oxide varistors and increased the withstand capability ofDC resistance. It’s widely  apply forarrester assembling in DC power transmission , DC converter stations and meetother DC high-voltage equipment protection product assembly requirements

High gradient metal oxide varistors are improved by thegeneral formula, mainly to change the doping formula so that the zinc oxideresistance of the grain size and the thickness of the crystal layer has changeddue to the increase in the gradient to improve the energy absorption ratio andalso makes the residual voltage ratio lower, suitable for small and small tanksuch as GIS arrester and closed combination of electrical assembly.