In order to solve the problem of clearing the DC fault of modular multilevel converter（MMC）

we put forward a fault clearing strategy of DC grid with double current transfer branches. In the strategy

by adding double current transfer branch and energy dissipation branch to the DC side of the MMC

the fault current is forced to both branches during the failure

so that the fault line can be disconnected at low voltages and small currents

and the DC grid can be quickly restored after fault isolation. The double-current transfer branch is installed on the DC bus

where the thyristor and capacitor are utilized to play the role of transferring the discharge energy of the converter capacitor

and the energy dissipation branch is installed on the DC line

which consumes the energy stored by the line through the ground resistance. Finally

PSCAD/EMTDC verifies the superior performance of the proposed strategy in fault removal and recovery

and its good economy in terms of device cost and number compared with other DC circuit breakers.