According to the lightning protection mechanism and the requirement of“off-ground”insulation of overhead ground wire

a new scheme of overhead grounding wire lightning protection and melting-ice system is proposed.The system consists of a new type of overhead ground wire with four（or three）layers and its auxiliary grounding equipment. And it can not only solve the problem of "off-ground" current heating of the overhead ground wire during ice coating in winter

but also improve its lightning protection performance. Taking a 220 kV overhead line as an example

the traditional overhead ground wire and the new lightning protection and melting-ice overhead ground wire system are used respectively. The two schemes are modeled on ATP-EMTP to compare their lightning protection effects. The simulation results show that the new lightning protection and melting-ice overhead ground wire system can significantly decrease the direct attack（or induction）lightning overvoltage rise rate and amplitude on the ground line

thus effectively improving the lightning protection effect of the overhead ground wire. In addition

based on the research results of the minimum ice-melting current of the traditional overhead ground wire

according to the principle of“the same minimum ice-melting heat capacity required when the outer surface area of the wire is the same”

the calculation method of the minimum ice-melting current of the new overhead ground wire is derived.