PROJECT TITLE :

Critical-Mode-Based Soft-Switching Modulation for High-Frequency Three-Phase Bi-Directional ACDC Converters

ABSTRACT:

For three-phase bidirectional ac-dc converters, a unique critical conduction mode-based modulation has been suggested in this study. Additionally, a reduction in switch-related loss is achieved through this modulation, making it especially beneficial for systems operating above hundreds of kHz with wide-band-gap power semiconductor devices in order to achieve high power density and efficiency while maintaining a low switching frequency. An ac-dc converter prototype with a power density of 127 W/in 3 is planned for a 25 kW silicon carbide-based high-frequency three-phase system, which is at least five times greater than commercial solutions. One low-cost microcontroller handles all the control duties, and these benefits have been shown experimentally in both inverter mode and rectifier mode. For this prototype, the suggested soft-switching modulation results in peak efficiency near to 99.0% even at high switching frequencies above 300 kHz.