Characterization of the Emission of an Electric Bus Inductive Charging in the 2 kHz to 150 kHz Range

The foreseen increasing penetration of the Electric Vehicle is causing concern about its impact on power quality, especially with respect to distortions in the frequency range from 2 kHz to 150 kHz, also known as supraharmonics. This relatively new power quality issue is recently getting more attention from the research community and the standard setting organizations. The main reason is the increasing presence in the grid of power electronics devices with switching frequencies of tens of kHz. Electric Vehicle chargers are among them and, therefore, their impact on supraharmonic distortion needs to be accurately characterized and modeled. This paper presents the characterization of an electric bus wireless charging, currently part of the EURAMET project MICEV. The aim of the work is to overcome the lack of knowledge on the supraharmonic emission due to the inductive charging of Electric Vehicles. The results of field measurements of an electric bus wireless charging are presented and a frequency analysis is performed according to IEC 61000-4-7 standard, studying the origin and the behavior of the supraharmonic spectral components.