500 kHz SiC- and GaN-Based Dual Active Bridge with Voltage Conversion Between 48 V and 650 V

Inhalt:
Bidirectional DC/DC converters are used in many applications. If the DC/DC converters use high switching frequencies they can not only be compact, but are also capable of reacting radically to transient changes. This paper presents a 2 kW Dual Active Bridge converter operating at 500 kHz with a high conversion ratio of 15. A peak efficiency of 96 % is reached. The converter uses wide-bandgap semiconductors on the input and output side, which leads to a high dv/dt and reduces switching losses in hard-switching operation points. However, ringing occurs at low power which can be reduced with the presented asymmetric dead time between the low- and high-side switch.