Standalone Current Sensor for Real-Time Supraharmonic Analysis (2–150 kHz) in Bidirectional Chargers for Electric Vehicles

Abstract:
The deployment of electric vehicle supply equipment (EVSE) has introduced significant challenges to power quality (PQ) due to the impact of power electronics. In particular, the high switching frequencies of power converters, typically within the supraharmonic range (2–150 kHz), are a significant concern. Supraharmonic distortion is widely recognized as a major stress factor for electrical equipment; however, no standardized requirements or limits currently exist for supraharmonic emissions. This study introduces a novel standalone current sensor capable of performing supraharmonic analysis at the edge, enabling real-time measurement under live operating conditions. The proposed sensor has been tested to evaluate the supraharmonic emissions generated by bidirectional EVSEs during charging and discharging processes, focusing on the conducted disturbances injected into the grid. The measurements account for varying impedance conditions in both the grid and the electric vehicle, allowing the detection and mitigation of localized and/or temporal supraharmonic quality issues.