Study and experiment of mobile DC de-icer for overhead ground wire

Serious icing disasters threaten the safe running of power system. Overhead ground wires are difficult to de-ice with common heat de-icing methods in some special areas. A mobile DC de-icer for the overhead ground wire is developed in this paper to realize flexible de-icing. A diesel generator provides the 50 Hz three-phase power supply. A rectifier transformer is used to step up the voltage and a rectifier is used to convert AC to DC. The 12-pulse rectification mode is adopted to reduce the current harmonics of the rectifier and to decrease the ripple of the DC output. Onsite experiment of the mobile DC de-icer for the overhead ground wire is performed on a GJ-70 typed overhead ground wire with the length of 4847 meters. A temperature rise of 7.0°C is achieved in 36 minutes under the DC de-icing voltage of 2700 V and current of 100 A. The result shows that the mobile DC de-icer for overhead ground wire can operate reliably and can meet the demand of flexible de-icing.