Method to assess the power quality impact of plug-in electric vehicles

This paper presents a probabilistic harmonic simulation method to study the power quality impact of electric vehicles (EV). The proposed method takes into account the random operating characteristics of the vehicles, such as random charging time, charging duration and vehicle locations. A multi- phase model of the primary and secondary systems is used to represent the study system. Extensive case studies have been conducted using the method and the measured EV data. The results reveal that the current versions of plug-in hybrid EVs have no significant harmonic impact on power systems. However, the Level 1 charger can increase the neutral to earth voltage at homes which could lead to increased stray voltage incidents.