THERMODYNAMIC MODEL OF CRITICAL ICE-MELTING CURRENT ON ICED TRANSMISSION-LINES

The thermal de-icing by Joule effect is a mostly valid way to prevent transmission-lines from the severe ice storm. A model was put forward to simulate the critical ice-melting current on iced conductor. Based on this model, the value of critical ice-melting current was calculated with various parameters, some of which were ignored in the earlier literatures, such as ice-layer heat conductivity, wind attack angle, and icing section shape. The results of the experiment and simulation show that the critical ice-melting current increase with wind speed, wind attack angle, and ice-layer heat conductivity, but decrease rapidly with ambient temperature and liquid water content. Moreover, the maximum difference between the results of simulation and experiment is about 9%, thus this model can be employed to estimate the engineering parameters in practical thermal de-icing projects.