Assessment and optimal passive-loop mitigation of power lines’ magnetic fields

This paper addresses the issue of the power frequency magnetic field in the vicinity of high voltage lines. Expressions are derived for the intrinsic power-frequency magnetic field. The mitigating effect of passive conductor loops installed below or above the active line conductors, is demonstrated. A further optimizable reduction in the magnetic field can be achieved by inserting properly-selected capacitors and/or resistors within the loop. The results indicated also that the field-reducing effect of the additional conductor loop will largely depend on the locations of these wires with respect to the linepsilas active conductors. There are optimal locations for which the mitigation will be most effective. A direct procedure is presented for identifying the optimal locations of the loop conductors as well as of the optimal loop impedance.