High Power Electric Powertrain for Commercial Aircraft Propulsion

In emerging aircraft technology, the electric powertrain is the main and crucial component in an electrified aircraft. The aircraft propulsion Electrical Machine (EM) design requirements are also unique compared to traction EM. The propulsion EM has to operate at high speed and frequency. Hence, the quality of the voltage shape must be better. It is different compared to traction EM, which can filter the current due to magnetic reserve in high-speed field weakening region. Hence, a unique propulsion EM, high-power inverter, and pulse-width modulation strategy is required to deploy in the electric powertrain of commercial aircraft. A high-power propulsion Induction Machine (IM) is designed and developed that includes a unique tuned coil principle and technology featuring variable cross-section windings that are combined with another original technology that achieves direct contact between coils and coolant. Secondly, a synchronous Pulse-Width Modulation (SPWM) strategy is proposed and developed to eliminate the issue of undesired harmonics in the IM-based propulsion drive. This is achieved by designing FPGA-based synchronous PWM strategy so that the improvement in the overall performance of the electric powertrain can be achieved. In addition to the propulsion EM and SPWM, a high-power inverter is also designed and implemented to fulfill the operational needs of commercial aircraft. Firstly, the proposed synchronous PWM strategy is validated in the simulation environment. It is also realized on MicroAutoBox-II dSPACE rapid control prototyping hardware and tested for record holder 1MW propulsion IM. The results show the efficacy of the proposed electric powertrain for commercial aircraft.