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AEROSPACE, DEFENSE & MARINE / Addressing the Top 10 Connectivity Challenges in Developing Electric Aircraft Addressing the Top 10 Connectivity Challenges in Developing Electric Aircraft 2 1. Significantly Higher Voltages (kV) and Power (MW) Applying high voltage cables and power systems is nothing new for electrical engineers acquainted with Ohms law (P=IxV). But applying appropriate technologies for hybrid and electric aircraft presents novel situations. By using a "follow-the-wire" design approach, EWIS engineers can help ensure that all the links—connectors, wiring, jackets/ insulation, converters, contactors, power sharing networks, and more—can handle the voltage and environmental conditions unique to electric aircraft. Higher voltages are found in the following situations: • Electrical systems for conventional aircraft employ 115VAC/400Hz and 270VDC with "high-voltage" (HV) power requirements typically limited to 230VAC. In eVTOL aircraft, the thrust required over rotor area for lift during vertical takeoff and hovering, referred to as disc loading, can necessitate fan speeds from 2,300 to 20,000 RPM delivered by brushless 800VDC motors. • HV alternating current (AC) is encountered in generators, power converters, and controllers employed in fast-charging stations. Other electrical differences include non-linear power- sharing networks and multi-directional charge paths. Of course, designing for higher voltage typically translates into using products with thicker dielectric materials and are consequently heavier, stiffer, and take up more space. Advanced power wiring must allow flexibility for routing and dynamic bending of pods and wings, with optimized wiring weight, cable cross sections, and consider ribbon-type (flat) cable geometries. Respective HV connector solutions must enable current carrying capability often up to 1,000 Amps in non- traditional connector geometries. These and other connectivity solutions must address the challenging power density, power frequency, and size, weight, and power (SWaP) requirements for electric aircraft. 2. Mitigation of Partial Discharge/Corona Effect Managing HV at altitude is more complicated than on the ground. That's because HV can ionize surrounding air particles more quickly with catastrophic effects, due to lower air densities at altitude as the less constrained particles can achieve higher velocities sooner. Released energy generates a corona discharge resulting in power losses through voids, cavities, and electrical treeing in insulation. Electrical discharges can occur across a voltage gap between two points/surfaces, because the high electrical field cannot be contained by the material(s) in the area. The discharge can also initiate electrical arcing, potentially igniting a fire. Selecting dielectric materials and constructions suited to HV conditions--such as corona- resistant polytetrafluoroethylene (PTFE)- -can minimize discharge risks due to insulation breakdown. Elimination of air bubbles/pockets (porosity) can be achieved by employing over-molding and insert molding around connector contacts. 3. Increased Reliability for Harsher Environment, Frequent Maintenance and Inspection, Shock, and Vibration eVTOL vehicles fly shorter distances than commercial aircraft and are anticipated to make numerous takeoffs and landings per day. Consequently, they require high reliability in interconnects that can withstand vibration and shock from more frequent landings and takeoffs. Reliability is essential because eVTOL flight paths may typically occur over densely populated urban environments. To help ensure performance, electronic/electrical Electric Vertical Takeoff and Landing (eVTOL) aircraft designers are addressing voltage and power challenges in batteries, pods, and fast-charging stations with advanced connectivity solutions Just as electric vehicles are revolutionizing the automotive industry, electric aircraft promise to boost the sustainability and convenience of air travel. Designers of urban-air/advanced-air mobility (UAM/AAM) "air taxis" and electric-powered vertical-takeoff-and-landing (eVTOL) vehicles face numerous challenges when connecting High Voltage (HV) and High Power (HP) systems. Electrical Wiring Interconnection Systems (EWIS) engineers and eVTOL aircraft designers are finding a wide range of solutions are now available to address these 10 connectivity challenges:

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