Suppression strategy for short-circuit current in loop-type DC microgrid

Abstract

In low-voltage dc microgrid, many power electronic devices may suffer from overvoltage or overcurrent when there's a short-circuit fault in lines. To improve the power supply reliability in dc microgrid, suitable protection strategy for suppressing short-circuit current in dc lines is indispensable. In this paper, a loop-type dc Microgrid with high power supply reliability is adopted. Furthermore, different short-circuit fault types in dc bus are discussed. And the influences of snubber circuits attach to switches, equivalent impedance of fault current freewheeling circuits and short-circuit fault point positions have been analyzed. The simulations and experiments results present the effectiveness of the proposed strategy.