The performance parameters of electric motors for aviation propulsion are: 1) specific power (SP), 2) reliability, and 3) efficiency. The Polarix ACTS motor provides a substantial enhancement of all three. This is the result of a new motor topology made possible by the integration of the inverter with the electro-mechanical current carrying elements. The topology has the following unique characteristics: 1) elemental motors distributed around the periphery, each with its independently controlled inverter with overall control from a master MCU, 2) the elemental motors contained by 3 conductors with a dedicated inverter at one end, and a short at the other and thus no turns, and 3) the planar arrangement of the conductors allows for MEMS type manufacturing.
This topology results in almost halving the volume and weight of the magnetic circuit and thus effectively doubling the specific power. Secondly, the large independent motor elements provide for massive redundancy and thus substantial higher reliability. Also, the elimination of turns and external wiring allows for greater copper utilization and thus higher efficiency.
The performance discussed in the proposal in parametric form (Figure 9) shows 30kW/kg specific power with stator cooling at 5W/cm2 at 99% efficiency excluding windage and core losses.
The state of the art includes both the motor and the inverter. We have built a number of motors with construction performance required for the proposed motor and likewise we have built numerous inverters and have tested the required currents voltage and power.
The program proposed here will integrate the various elements already demonstrated into a motor with power exceeding 50kW and specific power exceeding 10kW/kg and projected at 15W/kg.
We project that the phase II will demonstrate a motor in the 500kW range and with SP power above 20kW/kg.
Applications include airborne propulsion applications - manned and unmanned, covering the power range from 1kW to MWs of hub motors for driving propellers and rim motors driving fans. The latter will have a major impact on hybrid airplanes and the development of more advanced jet engine which will now have the ‘electric gearbox’ as part of the engine system. The motor will see applications in various aviation applications such as flight control actuator and many other electromechanical control and actuation of various subsystems.
Its unique characteristics of the Polarix ACTS motor are its very high specific power, light weight, high reliability, high efficiency and a low cost. These features lend it to a broad range of commercial applications, terrestrial marine and airborne applications such as generators for APUs, marine/UAV, airborne UAV, and terrestrial vehicles.