Active short-circuit protection method and device for direct-current looped network system

The invention relates to an active short-circuit protection method and device for a direct-current looped network system, and the method comprises the steps: detecting an input current, an output current and an output voltage of the direct-current looped network system, so as to obtain sampling data; judging whether a short-circuit feeder line occurs in the direct-current looped network system ornot according to the sampling data; and if the direct current looped network system has the short circuit feeder line, closing the direct current output of the short circuit feeder line. By detectingthe input current, the output current and the output voltage, the short-circuit state is judged, and when a short-circuit feeder line occurs, the direct-current output of the short-circuit feeder lineis closed in time, namely, the PWM signal of the short-circuit feeder line is closed, so that other feeder lines can be effectively prevented from being influenced by the short-circuit fault when theshort-circuit fault occurs,