The integration of advanced battery technologies is crucial for the success of More Electric Aircraft (MEA), enabling network stability and high-power supply for electrified aviation propulsion.

This paper presents a novel adaptive battery protection circuit with self-controlled precharge for versatile load management. The circuit ensures the safe operating area (SOA) of battery cells under all conditions, enhancing battery availability. It manages battery currents during startup, normal operation, failure, and reconfiguration, aiming to replace traditional electromechanical contactors and resistive precharge circuits. This solution is particularly suited for high-power applications such as electric drive trains and systems with multiple battery configurations requiring reconfiguration.

The circuit comprises a main contactor, fuse, precharge circuit, and low-ohmic bypass switch. The main contactor provides redundancy, while the fuse protects against malfunctions. The power electronic interface operates via a simple hardware design without software, ensuring fast and current-controlled startup, safe connection to the battery, and reliable overcurrent protection. If SOA is maintained, the battery remains safe even after short-circuit events.

The circuit responds immediately upon applying a minimum voltage, handling short circuits and precharge requirements during reconfiguration. In normal operation, a low-ohmic solid-state switch bypasses the active switching circuit, which takes over in precharge, failure, or reconfiguration modes. The analog control system self-adjusts to varying loads, ensuring reliability without exceeding current limits, making it ideal for safety-critical applications.

The test setup, designed for 800V and 300A continuous current, includes integrated safety features like temperature and switching frequency monitoring. Optional microcontroller or FPGA integration allows for health monitoring and flexible control.

The final paper will detail the circuit’s design and electrical performance, with results from real-world testing and comparisons to theoretical simulations.