Investigation of High Altitude/Tropospheric Correction Factors for Electric Aircraft Applications

With rising fuel costs and CO2 emissions, the aviation industry is moving rapidly toward increased electrification of aircraft, and power demand for propulsion and safety critical systems necessitates a move to on-board distribution voltages in excess of 1 kV. The increased stress experienced by cable insulation, connectors and other equipment, combined with extreme and dynamic environmental conditions experienced in flight, presents a number of technical challenges. This research project proposes to quantify the effect of atmospheric conditions on partial discharge thresholds in uprated aircraft electrical systems, and to derive atmospheric correction factors appropriate to in-service operating conditions to assist the aircraft electrical design engineer in the insulation coordination of modern aviation systems. The development of a controlled atmospheric test facility for the precise replication of in-flight conditions is outlined, and an initial visual assessment of partial discharge activity in an ex-service wire harness at a range of pressures is presented. We also present plans for the ongoing development of the facility and test capabilities.