Harmonic resonance risk of massive ultra fast charging station grid integration

Plug-in electric vehicle (PEV) is gaining steadily preference among consumers as they offer economically viable and environmentally friendly transportation solutions when compared to their gasoline powered counterparts. A decent charging station network coverage has been identified as the main enabler for the adoption of PEV. Therefore, the availability of ultrafast charging station (UFCS) is not only a technical prerequisite but also a key enabler for the consumer acceptance to bring the electric mobility to the next level. To facilitate the smooth integration of UFCS in the existing power grid, hence rapid uptake rate of PEV, this article elaborates on the analytical derivation of the norton equivalent for the study of harmonic resonance when several UFCSs are connected to the local medium voltage (MV) grid. The impedance of norton equivalent model explicitly represents the input admittance of power converter under small signal perturbation. A case study is performed on the Dutch Bronsbergen MV grid to which 10 UFCSs are connected and its impact on the grid resonance point is shown with harmonic distortion calculation.