Analysis of the flicker level generated by the grid-connection of a fleet of electric vehicles

Optimised strategies regarding the coordinated grid connection of a fleet of electric vehicles often consider the simultaneous connection of a large number of these vehicles. This may induce voltage fluctuations of significant amplitude and provoke objectionable light intensity variations when applied to lighting equipment, which is defined as flicker. Hence, it is important to study under which conditions flicker may arise in order to define optimised grid connection strategies which prevent this phenomenon from occuring. However, although the grid impact of electric vehicle fleets is an active area of research, very few papers have considered the flicker level which the grid connection of electric vehicles may generate. Hence, this paper addresses the flicker level induced by the step-by-step grid connection of a fleet of electric vehicles connected to the distribution network. Flicker level will be studied under different conditions in terms of grid short-circuit level, grid impedance angle and power consumption profiles of the electric vehicle fleet.