On the Measurement of Thickness of Ice Layers on Power Transmission Lines

Abstract

In this paper, measurement of ice and ice/water layer thickness on power transmission lines using Goubau modes at 1, 2.54 and 10 GHz is analyzed, simulated and discussed. Ice layer thicknesses change the phase and attenuation of Goubau mode propagation over a given line length. It is found feasible to determine layer thickness by measuring the phase and attenuation of the Goubau mode at a few GHz. In addition to the thickness, it is also possible, to determine the composition of the layer by measuring the different dielectric properties of ice, water and their mixture over a wide bandwidth to develop a database for comparison with measured data. The sensitivity of suggested instrumentation is sufficient for short line lengths (up to 1 m) or long lengths (several km). The implementation of instrumentation on long lines is still to be done but no major obstacles are foreseen. The decision to de-ice transmission line using any given and established techniques is facilitated if average ice thickness on transmission line between supporting transmission line towers can be measured.