ABSTRACT
Power lines were designed with overhead ground wires to protect against transient voltages induced from nearby lightning strokes to ground. Emphasis is put on protection against both direct and indirect lightning strokes. As the reliability of distribution power lines has become increasingly important, many researchers have been studying the effects of lightning-induced voltages on power distribution lines. The various conductors in a multiconductor system interact with each other in the induction process for lightning strokes to nearby ground. The voltage induced on an overhead line is caused by the interaction between various lightning return-stroke parameters and the parameters of the line. According to the electrogeometric model, the striking distance of a lightning stroke is proportional to the return-stroke current. Outages of an overhead power line may be caused by both direct and indirect lightning strokes, especially if the voltage withstand level of the line is low, for example, power distribution lines.
