Time-Domain Protection Scheme for Microgrids With Aggregated Inverter-Based Distributed Energy Resources

This paper proposes a time-domain-based protection scheme for radial and loop microgrid systems with inverter-based resources (IBRs), such as solar photovoltaic (PV) type-4 wind turbines. The is designed to function during both grid-interconnected grid-isolated modes. proposed provides an ultra-high-speed sub-cycle directional element aided low bandwidth communication between relays. Like comparison schemes, relays identify whether faults are in-zone or out-zone. based on time-domain superimposed quantities Park’s transformation algorithms. More specifically, the calculates positive-sequence direct component of transient energy faults. Superimposed voltage current calculated using delta filters decoupled double synchronous reference frame (DDSRF) filters. filtering method improves reliability when IBRs present. evaluated modified IEEE 34-bus distribution system simulated electromagnetic transients program.