DC power distribution network protection and control method

The invention discloses a direct-current power distribution network protection and control method, which comprises the following steps that: when a direct-current power distribution network is in closed-loop operation, each switch element acquires the overcurrent direction of the switch element and the overcurrent direction of a switch adjacent to the switch element; according to the overcurrent direction judged by the switch itself and the overcurrent direction of the switch adjacent to the switch itself, the fault occurrence position is judged, the fault voltage change rate is calculated, and the reclosing delay time of the switch element position piece corresponding to the fault voltage change rate is set according to the fault voltage change rate; when a fault occurs on the same line or bus where the switch is located, the switch element is switched on and off; when the fault occurs and the switch-off signal of the switch is received, an isolation fault signal is sent to a network; reclosing the fault swi