The performance of reduced magnetic field power lines: theory and measurements on an operating line

Power engineers have been trying to find transmission line geometries that will reduce fields. One of the reduced field geometries is the double circuit, low reactance line. The results of a measurement and a theoretical program to study the magnetic field performance of such a double circuit 230 kV line with only one circuit energized and with both circuits paralleled in a low reactance configuration are presented. The measurements show that the reduced field line is more sensitive to deviations from balanced currents.<>