Investigating the performance of grid-forming hybrid photovoltaic systems in residential A/C dominated networks: An analysis during distribution feeder restoration and FIDVR

Abstract

Grid-forming inverters must optimally transfer power from dc-coupled photovoltaic arrays and batteries into an ac grid. Further, they must be able to restore single-phase induction motors (SPIMs) and withstand fault-induced delayed-voltage-recovery (FIDVR) events. These resilience and reliability challenges are addressed here by: (i) engineering a controller to optimally operate dc-coupled hybrid resources; (ii) modeling residential air-conditioning compressors for restoration/FIDVR studies; and (iii) analyzing SPIM thermal-relay performance under limited inverter currents and designing an electronic protection for stalled SPIMs. These contributions are demonstrated via electromagnetic-transient simulations to satisfy recommendations by the North American Electric Reliability Corporation.