Electromagnetic field intensity on cross-arm structures caused by electrical arcing

Unfavorable weather conditions and prolonged electrical stress can lead to corona discharge and electrical arcing on high voltage insulators. The intensity of electromagnetic radiation emitted from an electrical arc is determined at different locations on cross-arm structures. Two common cross arm configurations available within the power network are studied. The results show that electrical arcing on faulty insulators can increase the level of field in the other insulators situated on the same cross-arm. This electrical stress can contribute to the aging of high voltage insulators. The results for the two cross-arm systems show that an optimum configuration can be devised for which the electromagnetic stress on insulators is minimised when electrical arcing appears on a faulty insulator.