Distribution-Level Impacts of Plug-in Electric Vehicle Charging on the Transmission System during Fault Conditions

Abstract

Transmission planners must identify and plan for the potential impacts of widespread EV charging on the reliability of the grid. This paper examines how the addition of significant EV charging loads would affect regions of the grid that are susceptible to fault induced delayed voltage recovery (or FIDVR). We find that EV chargers that cease drawing current at the onset of faults and that delay drawing current until sometime after a fault has cleared will not exacerbate FIDVR and label this behavior grid friendly. We find that EV chargers that do not cease drawing current at the onset of these faults or that resume drawing current immediately after the fault has cleared will exacerbate FIDVR and label this behavior grid unfriendly. We emphasize that modeling and information on EV charging behaviors is currently limited and recommend engagement by the transmission planning community with the EV manufacturing community to improve this situation.