Design and Analysis of Dual Stator PMSM With Separately Controlled Dual Three-Phase Winding for eVTOL Propulsion

The propulsion system of the electric-powered vertical take-off and landing aircraft requires a high level of performances, including power density, efficiency, noise vibration and harshness, and fault tolerance. Among many types of conventional electric motor, the outer rotor surface-mounted permanent magnet synchronous motor (SPMSM) is widely used for its high power density and low torque pulsation. However, these advantages are degraded when the multiphase winding is applied to secure the fault-tolerance characteristics. To overcome the limit of conventional motor topology, the dual stator permanent magnet synchronous motor with separately controlled dual three-phase winding is proposed. The advantages of the proposed topology are resulted from the feature of mechanical, electrical, and magnetic isolation. To maximize the distinctive feature, a design process considering separated current vector control (SCVC) method is established. A design example is presented to demonstrate the impacts of the proposed design process considering SCVC on the power density maximization, torque harmonic reduction, and efficiency improvement. Finally, the experimental verification is presented to validate the proposed design and control techniques.