T20.1 - Power Gyrator for EV Charging Applications

This work presents a high-frequency isolated converter based on the gyrator principle for EV battery charging. The proposed gyrator-based topology exhibits inherent current-source behavior and supports voltage-source operation. Gyrator functionality is achieved by embedding a resonant network into a low-coupling E-core transformer with equal air gaps, yielding a controlled coupling coefficient. A 10 kW, 50 kHz prototype was built and tested. In current-source mode, it operates from a 560 V DC bus and delivers flat output current over a 350 V–480 V battery range with approximately 96.4% efficiency. By varying frequency, the converter can also act as a voltage DC to DC transformer. The proposed concept provides a building block for multicell chargers with seamless power scaling.