Multiphase Buck Converter for the Next Generation of Megawatt Charging
The electrification of heavy-duty vehicles is placing new demands on the power electronics used in charging systems. To efficiently and reliably deliver the high charging power required by future megawatt charging infrastructures, AIT is developing innovative DC/DC converter technologies for use in high-power charging systems.
The multiphase buck converter serves as the final power conversion stage between the charging infrastructure and the vehicle battery. The system processes input voltages of up to 1,500 volts DC and provides a controllable output voltage of up to 1,250 volts DC. This allows the charging power to be optimally adapted to the requirements of modern high-voltage battery systems.
The technology is based on a ten-phase interleaved buck topology with a total power output of up to 200 kilowatts. By distributing the current across ten phases operating in parallel, current ripple is significantly reduced, the load on individual components is minimized, and uniform current distribution is ensured. This increases both the efficiency and the reliability of the overall system.
Modern silicon carbide (SiC) semiconductors are used for the power electronics. These enable high switching frequencies and low losses even at very high voltages and currents. The system is complemented by a high-performance liquid cooling system that ensures effective heat dissipation and stable operation at high power densities.
The developed buck converter is part of the European DC Megacharger project (formerly MEDUSA), which develops ultra-fast charging solutions for electric commercial vehicles. In the overall architecture, the converter handles the direct connection to the vehicle battery, while galvanic isolation is already achieved in an upstream medium-voltage DC/DC stage. This allows the final power stage to be designed to be particularly compact, efficient, and cost-effective.
With this technology, AIT is contributing to the development of megawatt-scale charging infrastructures that will enable charging capacities of several megawatts in the future, thereby decisively supporting the electrification of European freight and bus transport.
Further information: www.dc-megacharger.com
