Model Predictive Control of a Fault-Tolerant- Hybrid Excitation Axial Field-Flux-Switching Permanent Magnet Motor

Fault-Tolerant Hybrid Excited Axial Field Flux-Switching (FT-HEAFFS) motor is a new type of doubly salient stator-type permanent magnet motor, which combines the advantages flux switching motor and hybrid excitation motor. This motor has compact structure, high power density, high efficiency and strong anti-demagnetization capability. The additional excitation winding makes the air gap magnetic field adjustable, which can increase the output torque and extend the speed range. It is suitable for use in the system of frequency conversion and speed regulation of electric vehicles. To improve the performance of the fault-tolerant-hybrid excitation axial field flux-switching (FT-HEAFFS) motor and attain the minimum copper loss, a fault-tolerant control method based on model predictive control algorithm is proposed. Considering a 6 stator slots/13- rotor poles FT-HEAFFS machine as the control object, under the open circuit failure of single-phase winding, the minimum cropper loss fault-tolerant method based on the model predictive torque control (MPTC) and direct torque control are studied and analysed, respectively. The feasibility and effectiveness of the proposed fault-tolerant control method are verified. The research results showed that both methods could make the speed, torque and stator flux-linkage almost unchanged, ensuring the stable operation of the system. Compared with direct torque control, the model predictive flux control had smaller flux-linkage ripple before and after the open circuit failure.