Implementation of a Solid-State Power Controller for High-Voltage DC Grids in Aircraft

Conventional electrical distribution systems onboard aircraft use a three-phase system with a typical voltage of 115 VAC or 230 VAC to supply electrical loads. Future aircraft demand more electric power due to the replacement of hydraulic and pneumatic systems by electrical ones and the increased use of multimedia entertainment systems. However, the aircraft weight can be decreased if a high-voltage direct current (HVDC) grid with a voltage level of ±270 VDC or 540 VDC is implemented to supply the electrical loads. These higher voltages reduce cable weight, but are a new challenge for solid-state power controllers (SSPC), which are used as protection devices for cables and loads. Currently available SSPCs are limited to lower voltages and currents mainly because of the available power semiconductors. A SSPC for aircraft applications with a nominal voltage of 540 VDC and a nominal load current of 10 A has been developed at the Helmut Schmidt University in Hamburg in cooperation with Airbus Group Innovation using SiC-MOSFETs and has been tested. In this paper the design and experimental results are presented. The SSPC is able to supply itself from the high voltage autarkic and can accomplish various functions