Voltage-Dependent EV Battery Charger Models for Power Flow and Harmonic Emission Studies

The ongoing large-scale electrification of road transportation sector will result in significantly increased demands from electric vehicle (EV) battery chargers (EVBCs), impacting not only network power flows and load profiles, but also power quality levels and harmonic emissions. Typically, on-board EVBCs are modelled as a "constant power" load type, without considering their voltage-dependent characteristics will result in errors in estimated component loading and harmonic emission limits, as well as required network upgrades to connect the new EV loads. This paper presents details of the development of two component-based EVBC models that incorporate both voltage dependency and state-of-charge dependency of their power demand and harmonic emission characteristics. The developed models are experimentally validated using actual measurement data under both sinusoidal and distorted input voltage supply conditions, demonstrating their applicability for assessing impact of EVBCs on network power flows and harmonic emission levels.