Differential Protection Scheme for A Micro Grid with Inverter-Type Sources Based On Positive Sequence Fault Currents

The microgrid (MG) is a coordinated collection of different distributed generation (DG) typesthatsupply local demandthrough distribution network. MG may operate in two modes: grid-connected (GC), and islanded (IS)modes.The fault current valuevaries significantly between the GC IS mode for with inverter-based generators(IBDGs). currents are minimal owing to power electronics equipment have limited carrying capacity. Therefore, coordination traditional overcurrent (OC) protection difficult these operation modes. comprehensive scheme should be established safeguard against all kinds faults. main strategy proposed this paperis positive sequence differential scheme. envisioned concept can overcome protective device problems, types detected during both modes radial andloop configurations. validation design performed using PSCAD/EMTDC software. results indicate that maximum clearing time modeisof 31.5 ms 34 respectively. Compared other schemes, has faster less expensive.