High voltage DC grids are developing in more terminals and with larger transmission capacity

thus the requirements for DC circuit breakers (DCCB) will continue to rise. Conventional methods only use the faulty line DCCB to withstand the fault stress

and therefore this paper presents a coordination method of multiple DCCBs to protect the system. As many adjacent DCCBs are tripped to interrupt the fault current

the fault energy is shared

and the requirement for the faulty line DCCB is reduced. Moreover

the adjacent DCCBs are actively controlled to help system recovery. The primary protection

backup protection

and reclosing logic of multiple DCCBs are studied. Simulations confirm that the proposed control reduces the energy dissipation requirement of faulty line DCCB by approximately 30%-42%

the required current rating for IGBTs is reduced

and the system recovery time is also reduced by 20–40 ms.