Fast protection strategy for monopole grounding fault of low-voltage DC microgrid

•This paper presents a low-voltage DC microgrid ground short-circuit fault protection system based on positive channel metal oxide semiconductor (PMOS).•In case of ground short-circuit fault in DC microgrid, the coupling energy of the short-circuit current makes the PMOS to be turned off reliably.•In addition, because the primary inductance of the transformer plays a certain current limiting role, the turn-off current of PMOS will not increase sharply.