ABSTRACT
To proceed toward possible adoption of metal oxides varistor (MOV) in power system protection, the Electric Power Research Institute selected two power equipment manufacturers, McGraw-Edison and Westinghouse Electric to conduct a research project targeting the operational design of the largest MOV in power system installations. Electric utilities are beginning to employ metal oxide semiconductors in other applications such as series capacitor protection equipment, vacuum interrupter switch gear, and capacitor voltage transformers. High current surges may enter a neighboring line with different surge impedance, resulting in a series of reflections that may amplify the strength of the current pulse severalfold. Incidence of H. V. Surges on Ferromagnets presents calculations of surge fields and the positive role a new protective element may serve in protecting against high current surges in high voltage transmission systems. Gapped arresters offer significant protection, but with certain limitations, especially that their response to many lightning surges is not fast enough.
