An Investigation of Corona Loss and Radio Interference from Transmission Line Conductors at High Direct Voltages

Corona loss and radio interference (RI) from one single Drake conductor and one Drake 2-conductor bundle, installed on two short test lines have been measured at direct voltages up to 600 kv, positive and negative, under a variety of weather conditions and voltage levels. The Drake conductor is a 1.108-inch-diameter 795-MCM (thousand circular mil) ACSR (aluminum cable steel-reinforced) conductor with 16 outer strands of aluminum each of 0.175-inch diameter. Comparisons of corona-loss performance of these two conductor systems, obtained from both short-term voltage increment tests and from long-term constant voltage tests, are given. Equipment for loss measurements, including a shielding method which substantially reduces the measurement errors ordinarily introduced by losses through solid line insulation, is described. Results obtained from occasional surveys of RI at frequencies up to 10 mc (megacycles) are presented.