Installation on a community-sized DC microgrid system and suggestion on a DC short-circuit test procedure

摘要

Installation and operation of a real DC microgrid (µG) with variable energy sources are studied in this paper. Concretely, the paper presents main distributed energy sources as well as protective devices to construct the low-voltage DC µG. Simulation on faulted and normal operation modes of the DC µG is also mentioned to observe signals of voltage, current, and power. Based on the simulation results, it is proposed that operation of fast acting fuses (FAFs) is very efficient to replace no-fuse breakers (NFBs) at some certain locations for protecting DC microgrids. Next, planning for actual short-circuit (SC) test procedures at the DC microgrid is performed, which focuses on staged fault tests containing pole-to-pole and pole-to-ground faults. Performance of SC test procedures is to validate estimation of fault currents and the DC protection system proposed. As a result, the paper indicates new contributions on building the real community-sized DC µG and suggestions on doing staged short-circuit tests.