Coordinated control of DC circuit breakers in multilink HVDC grid

High voltage DC grid is developing towards more terminals and larger transmission capacity, thus the requirements for circuit breakers (DCCB) will rise. The conventional methods only use faulty line DCCB to withstand fault stress, while this paper presents a coordination method of multiple DCCBs protect system. As many adjacent are tripped interrupt current, energy shared, requirement reduced. Moreover, actively controlled help system recovery. primary protection, backup reclosing logic studied. Simulation confirms that proposed control reduces dissipation by around 30–42 %, required current rating IGBTs reduced, recovery time reduced 20–40 ms.