DC Miniature Grid to Test Electrical System Configurations of Future Electric Aircraft

Kurzfassung

The expected rise in air traffic, increasing fuel prices, and climate considerations are accelerating the shift from conventional aircraft toward More Electric Aircraft (MEA) and, ultimately, All Electric Aircraft (AEA). Meeting the significantly higher power demand requires a fundamental redesign of the electrical system. Direct Current (DC) grids are promising candidates, offering efficient integration of batteries and fuel cells, reduced losses, lower weight, and simpler control. However, their implementation in aircraft still presents major challenges. DC grids have much lower inertia than AC systems, which strongly affects fault propagation, detection, and protection. Their fault behavior, the need for galvanic isolation, and the lack of a natural zero crossing, which complicates safe load disconnection, remain active research topics. To support future design decisions, this paper introduces a miniature low-voltage DC test bench that enables systematic investigation of DC grid behavior. It allows analysis of load connection and disconnection, comparison of unipolar and bipolar grid architectures, evaluation of isolated versus non-isolated converters, hardware-in-the-loop testing, implementation of energy management strategies, and controlled fault injection. The setup includes two sub-grids with configurable loads totaling 45 kW and an adjustable bus voltage up to 60 V. This test environment provides an essential foundation for improving power quality, fault protection, and energy management in future aircraft electrical systems.