Research of metal oxide non-linear resistance current-voltage characteristic testing

As the main appliance for overvoltage protection in electric system, the characteristic of Metal Oxide Surge Arresters (MOA) is decided by the unit residual voltage of non linear resistance. The article discusses the advantages and the disadvantages of several existing residual voltage testing methods. On this basis, the author has developed a new testing instrument that uses current controlling method to test the residual voltage.