Evaluation of Grid Harmonic Disturbances Injected by DC Electric Vehicle Charging Stations

The rapid adoption of Electric Vehicles requires advancements in Electric Vehicle Supply Equipment to accommodate the demand for enhanced performance. Commercial chargers now enable vehicles to inject power into the grid. However, the operation of the chargers introduces also distortions, in particular when multiple chargers operate simultaneously at the same node. This paper investigates the interaction between two different DC charging stations: one unidirectional and the other bidirectional. Then the analysis is extended to the harmonic interaction between the chargers. The results demonstrate the significant influence of the charger operation on grid power quality and highlight the importance of managing harmonic distortion.