Performance Assessment of Distance Protection of PV-Integrated Microgrids

The unpredictable magnitude and phase angle of PV-integrated microgrids (PV-MGs) makes overcurrent protection highly unreliable. This paper investigates distance protection as an alternative to overcurrent protection for fault detection and allocation in PV-MGs through PSCAD simulations. The MG is integrated with distributed photovoltaic and synchronous generators (PVDGs) and (SDGs). Several case studies of solid and non-solid three-phase, line to line and line to ground faults on an MG feeder are examined. The paper investigates the fault behavior of both PVDGs and SDGs with respect to distance protection. The effect of altering the grid-support settings of the PV inverter (PVI) on the performance of the distance relay is also studied.