According to the situation of existing ice-melting power supply， a novel topology of cascaded ice-melting DC power with voltage source converter（VSC） power units which based on insulated gate bipolar transistor（IGBT） chopper voltage regulation circuit is proposed. The operation mode of VSC power unit and the operation characteristics of cascaded ice-melting DC power are analyzed. Combining with the topology features of the ice-melting power supply， a new combined control strategy is proposed， which includes the unit power factor pulse width modulation（PWM） control for VSC power unit and chop voltage regulation control with six-fold phase-shifting. According to the application method of ice-melting power supply， a new three-phase automation control switchover strategy based on ice-melting power access method ofone-line out and two-line return” is proposed. The switchover method is given and analyzed in detail， and the strategy for fault in DC side is analyzed too. The test results show that the ice-melting power supply has such features as stable and adjustable voltage and constant current output so that it can effectively accomplish automation ice-melting function， and the power quality parameters are obviously better than those of existing other kinds of ice-melting power supply.