High Power-Density, Bi-Directional, 48 V to 12 V Converter using eGaN® FETs for Next Generation BEV’s

Inhalt:
The evolution of the low voltage electrical system in motor vehicles is beginning to challenge the need for multiple low-voltage cable harnesses within a vehicle. Supporting both 48 V and 12 V systems adds weight, cost and power loss. This paper presents an analysis of the operating voltage levels of the two voltage harnesses to define the design parameters for a LLC converter that can operate and comply with the unrestricted voltage requirements of each cable harness. The converter is experimentally verified using a 750 W capable, high efficiency, 23 mm x 18 mm x 10 mm size, narrow voltage regulation range, bi-directional LLC module using a 3:1 transformer, which can be used to distribute power to 12 V loads using the 48 V cable harness. The module can be paralleled without additional hardware to increase power.