Advantages of a Variable Board Supply Voltage in All-Electric Aircraft with Regard to Cosmic Radiation Induced Failures

The decarbonisation of the aircraft sector relies on electrification of the propulsion system. For very high power requirements in the megawatt range, the application of a high DC voltage for the board supply grid is beneficial to increase the power density. The failure rate of power semiconductors is increased with higher altitude and high blocking voltage. In this publication, a variable supply grid voltage is proposed to satisfy the reliability requirements while also allowing for a high voltage during the phase of high power demand.