Abstract
In this paper, the efficiency benefits of adopting Silicon−Carbide devices for electric vehicle applications are studied. A hybrid time and frequency domain-based simulation tool is developed for the Silicon−Carbide (SiC) traction inverter modeling. The tool provides steady-state results with comparable accuracy to standard time domain methods and achieves a factor of thousand reductions in time when simulating a large number of operating points. Especially, the impact of temperature-dependent device losses has been considered to ensure the simulation precision. Next, a vehicle-level modeling is developed to evaluate the impact of the inverter efficiency on the endurance mileage increase of vehicles. It is found that, by applying Silicon−Carbide devices, the energy consumption of the inverter can be greatly reduced by 3/4 under WLTC (World light light-duty vehicle test cycle) profile. It can be transformed into a mileage endurance increase of 3−5%. The impact of the drive cycle profile and the vehicle’s drag coefficient on the endurance mileage are evaluated as well. In addition, an economic/cost model is developed for selecting the “optimal” chip paralleling number for Silicon−Carbide power modules. Interestingly, the results indicate that this number should be slightly overdesigned to achieve the most cost saving from the system point of view.