Design of a High Power Density 1 MVA Three-Level Inverter for Electric Aircraft Propulsion

The development of megavolt-ampere (MVA)-class three-level inverters has become the focus in advancing electric aircraft propulsion systems. In this article, a highly power-dense three-level inverter design is demonstrated, targeting 1 MVA output power at a 1.5 kV DC bus voltage. The design focuses on optimizing the inverter's power density at both the system and component levels, including topology and component selection, power stage layout, lightweight bus bar design, as well as cooling system and EMI filter designs. Through comprehensive optimization, the designed inverter achieves a total weight of only 22.57 kg and a gravimetric power density of over 44.3 kVA/kg, setting a new benchmark for MVA-class electric aircraft propulsion. A prototype has been fabricated and tested under laboratory conditions, with experimental results validating both the electrical and thermal performance of the proposed inverter, confirming its capability for high-efficiency operation in demanding aerospace environments.