Harmonic Emission Modelling of Electric Vehicle Chargers

In emerging fast-charging stations, DC fast chargers (DCFCs) are employed which rely on power electronics and control to achieve the required performance. Harmonic emission induced by the complex system behavior is of great concern in the DCFC system. This paper proposes a harmonic emission model for the typical electric vehicle charger design, i.e., two-level active front end. The technique is based on the Fourier series method and the impedance model which is able to reveal the harmonic current emission of DCFCs under different grid conditions. Time-domain simulations are presented subsequently to validate the proposed model.