Design and Environmental Performance of Rectangular Bipolar Cables for All-Electric Wide-Body Aircraft

Advancing power cable architecture is crucial for enabling greater power delivery while simultaneously minimizing the overall system weight in future all-electric large-scale aircraft platforms. At high altitudes, the cable's surface area plays a critical role in determining both convective and radiative heat transfer, especially since reduced air pressure limits convection. Among the various geometrical designs, the rectangular configuration offers a more extensive contact surface with the surrounding environment compared to cylindrical or cuboid counterparts of equivalent cross-sectional dimensions, thereby promoting more efficient thermal dissipation. This study focuses on developing bipolar MVDC power cables, emphasizing rectangular designs that improve thermal behavior while reducing weight and cross-sectional dimensions. The ±5 kV cables are designed to operate in two different conditions: one at 101.325 kPa pressure (atmospheric pressure) and 1000 A current, and the other at 18.8 kPa pressure and 450 A current. This study examines the performance of rectangular bipolar power cables in comparison to alternative geometric configurations, including cuboid and traditional cylindrical designs. The findings suggest that rectangular bipolar cable systems possess a lower weight compared to other cable systems. Moreover, in comparing two conditions—101.325 kPa pressure with 1000 A current which is the situation at take-off, and 18.8 kPa pressure with 450 A for cruising time—the former design bears more weight and cross-sectional area. Despite the decrease in convective heat transfer under lower pressures, the reduced current demand at 18.8 kPa also leads to lower weight and cross-sectional area requirements. In cable design, prioritizing the worst-case scenario, such as designing for 101.325 kPa pressure with 1000 A current, is crucial. Therefore, designers should keep this scenario in mind to ensure optimal cable performance.