Auxiliary Power Module (APM) plays a crucial role in efficiently delivering power from power battery to various auxiliary systems and components in Electric Vehicles (EVs). Such systems, including lighting, infotainment, self driving system, and other electrical loads, which require a reliable power source. High power density is essential design target for APM, as it not only saves value space and weight in Electrical Vehicle, but also meets the power demands of the auxiliary systems effectively. This article introduces a cutting-edge design for a 3.5kWAPM that is compatible with both 400V and 800V battery system. The proposed APM topology employs a 650V Gallium Nitride (GaN) switches operated at 500kHz high switching frequency to significantly reduce passive component sizes. The GaN based design can reach more than 15kW/lit power density, while achieving a 98.54% peak efficiency.
