Extra-high-voltage direct-current circuit breaker, control method and equipment thereof and medium

The invention discloses an extra-high-voltage direct-current circuit breaker which comprises two 400kV direct-current circuit breaker units which are connected in series. The 400kV direct-current circuit breaker unit comprises a 400kV direct-current circuit breaker, a left isolating switch, a right isolating switch and a main bypass switch, and the left isolating switch, the 400kV direct-current circuit breaker and the right isolating switch are sequentially connected in series and then connected with the main bypass switch in parallel; wherein the two ends of the main bypass switch are respectively used as the two ends of the extra-high voltage direct current circuit breaker. The invention further discloses a control method and device of the extra-high voltage direct current circuit breaker and a medium. Any 400 kV direct current circuit breaker is controlled to be put into operation or quit operation. According to the technical scheme, the maintenance convenience of the extra-high-voltage direct-current cir