Evaluating Conducted Emissions up to 150 kHz from DC Electric Vehicle Charging Stations

Electric vehicle charging stations (EVCSs), which are known EMI sources, are expected to face upcoming standardized limits in the frequency range up to 150 kHz (also known as the supraharmonic spectrum). However, the adequacy of existing compliance tests for this range has received little attention thus far. This work examines the emissions of three high-power EVCSs under varying loads to examine whether existing compliance tests accurately assess their EMI levels. The results show significant differences between EVCSs, but existing compliance tests underestimated the EMI of all of them. Therefore, this study concludes that existing compliance test procedures are insufficient for low-frequency conducted emissions and thus need updating.