Highly efficient bidirectional Silicon Carbide power converter for Electric Vehicle flywheel emulator

Flywheels are nowadays a solution for the dynamic charging of electric vehicles since they act as transient energy storage. The need of a top efficient reversible power converter for the flywheel system is crucial to assure high dynamic performance. The paper presents the design of a 50kW highly efficient bidirectional three-phase DC-AC inverter involving most recent Silicon carbide metal oxide semiconductor field effect transistors and its experimental validation on home-made emulator. Highest efficiency in reversible mode, compactness and thermal enhancement are the target objectives that have been achieved. The converter prototype is evaluated on an original Pulse Width Modulation testing-bench able to emulate the working of the flywheel system. High frequency Pulse Width Modulation switching, speed cycle operating and thermal losses are evaluated. Also an efficiency above 99% for the converter has been attained, enabling a robust functioning of the flywheel system emulator able to perform specific charging profiles.