Improved Optimal Fault-Tolerant Control Considering Thermal Balance for Six-Phase PMSM in Aviation Electric Propulsion Application

An improved optimal fault-tolerant control (IOFTC) strategy, which considers thermal balance, is proposed for the six-phase fault-tolerant permanent magnet synchronous motor (FTPMSM) in the aviation electric propulsion area. This strategy addresses localized overheating in motor winding due to imbalanced phase currents during fault-tolerant operation. First, the electromagnetic torque model and the thermal model of FTPMSM are proposed, enabling precise calculation of the motor's output torque and temperature. Then, the IOFTC is proposed to reduce the maximum winding temperature during fault-tolerant operation. Additionally, a simplified solution method is proposed for the six-phase FTPMSM to facilitate the application of the IOFTC in engineering. Finally, the effectiveness of the IOFTC is validated on a simulation platform, which can ensure stable output torque and significantly reduce the maximum winding temperature during fault-tolerant operation, thereby enhancing the motor's electromagnetic torque output under fault conditions.