Less Iron and More Switches Increase Range

Current prototype motors and inverters for small aircraft electric propulsion have impressive efficiency of about 95 and 97% and typical power density of a little over 2kw/kg and 5kw/kg respectively. We can improve each of these metrics with a rigid winding which is formed in situ to increase slot fill and a 99.5% efficient inverter based on massively parallel, wide bandgap power switches. With independent “Brains” and “Brawn” sections, the inverter is scalable and can be distributed within the motor case, allowing fault tolerance and thermal integration benefits. The reduced weight and cooling needs represent an effective range enhancement of about 8% when configured for the X-57 cruise motors.