Direct-current circuit breaker

The invention belongs to the technical field of circuit breakers, and particularly relates to a direct-current circuit breaker, which comprises a switch, a control unit and a control protection branch, and is characterized in that the control protection branch is used for controlling the direct-current circuit breaker to be disconnected when a direct-current short-circuit fault occurs; and the control unit is used for judging whether a direct-current short-circuit fault occurs or not according to the voltage and current of the direct-current circuit breaker acquired in real time, so that when the direct-current short-circuit fault occurs, the controller controls the driving unit to control the protection branch to control the breaking action of the direct-current circuit breaker. Through timely control of the control unit, the control process of the circuit breaker becomes extremely short, so that the working time of the whole circuit breaker is shortened, the breaking speed is improved, and the control unit