Redesign of high-performance power converters for heavy-duty electric vehicles
The main objective of the RHODaS project is to improve the efficiency of electric powertrains with integrated motor drive (IMD) and distributed multi-wheel drive architecture (>10 tons; 100–150 kW per axle), while reducing their size and cost through the use of novel semiconductor materials. Therefore, a key research focus was on the development of multilevel power converters for heavy-duty vehicles using new semiconductor materials such as GaN and SiC to improve the architecture’s efficiency, power density, and reliability. This project presents a 150-kW hybrid T-type multilevel inverter.
The presented hybrid T-type inverter utilizes a combination of new WBG materials to improve efficiency, particularly under partial-load conditions. A peak efficiency of 99% was measured in three-stage operation and 98.6% in two-stage operation. Although a high power density of 60 kW/l is achieved, the system uses a modular design to improve serviceability. The inverter is designed for a DC bus voltage of up to 1000 V and is intended for use with the latest 800-V batteries.
