Fraunhofer IZM has revolutionized electric vehicle (EV) charging technology with the development of a new on-board charger (OBC) that offers twice the performance at half the size, and includes bidirectional capabilities. Traditional high power charging (HPC) stations can charge EV batteries rapidly, but require large, external DC chargers. In contrast, AC chargers, which are more common, provide slower charging due to the limitations of current OBCs. These conventional OBCs are bulky, manually assembled, and unidirectional, limiting their efficiency and versatility. Fraunhofer IZM’s innovative OBC, however, integrates advanced power electronics, including a sinus amplitude converter (SAC) with gallium nitride (GaN) semiconductors, allowing high-frequency switching and efficient power conversion. This breakthrough reduces the size and cost of the OBC while doubling its charging capacity to 22 kW.
Additionally, the new OBC features a planar Power Factor Correction (PFC) inductor, which is smaller, machine-made, and operates efficiently at high frequencies. The compact design, achieved through smart packaging and interconnection techniques, makes the OBC only three cubic decimeters in volume. This efficient design supports both 400V and 800V batteries and boasts an impressive efficiency of over 97%. Moreover, its bidirectional capability enables the OBC to feed power back into the grid, supporting the vision of EVs as a distributed energy storage network. This innovation, supported by the ECSEL JU initiative under the Horizon 2020 program, will be showcased at the PCIM Europe expo in Nuremberg, highlighting its potential to significantly impact the future of e-mobility and the green energy transition.
