Abstract
In order to investigate the transient phenomenon induced by lightning strokes or switching operations, unattended long-term transient current measurements were obtained in a several mannar. One is the transient current flowing through the Cable Covering Protection Units of the EHV cable line measurement to study sheath over voltage protection. The other is the transient current measurement flowing through the overhead line and the cable conductor connected each other. In case of the EHV cable line, switching surge currents were measured. Beside the case of the overhead line, lightning surge currents were measured. There are good agreement between measured data and the results of EMTP simulation.
