The icing of subway catenary will cause the pantograph unable to take current normally

or even cause the damage or fracture of the pantograph

which will seriously affect the safe operation of the subway. DC ice-melting is the best way to eliminate the icing of subway catenary. This paper firstly analyzes the working principle of the fullbridge MMC type DC ice-melting device

then gives the design method of the main circuit parameters and control strategy of the DC ice-melting device

and finally designs a dc ice-melting device with rated capacity of 6 MW and rated voltage of 3 kV

which can melt ice of 40 km uplink and downlink catenary at the same time. Meanwhile

the PSCAD simulation system is built. The simulation results show that the DC ice-melting device designed in this paper can meet the ice-melting demand of the subway catenary

and can be used for zero current rising

low current harmonic

small bridge arm circulation and good inter-module capacitive voltage balance.