A Method for Analysis of Radio Noise on High-Voltage Transmission Lines

A technique is described for approximating the effect of various factors on the radio noise level, due to conductor corona, on EHV transmission lines. The technique is essentially one of comparison. Relations are given in the Appendix for calculating the conductor gradients and results are presented in curve form. The application is intended only for comparison of radio noise generated by conductor corona on ac lines, with conductors ranging only from 0.3 to 1.3 inches radius (1.5 to 3.3 cm) and for the frequency range from about 0.2 to 1.6 MHz. If an existing line has been evaluated statistically the technique can be used to approximate the radio noise level of another line. A relation is also given for obtaining curves of 3-phase voltage to conductor radius for the same radio noise generation. Because of possible conductor surface differences and environmental differences, which cannot be too accurately evaluated, care is necessary in any final estimation of the average radio noise level.