Abstract:
Finite-control-set model predictive torque and flux control (FCS-MPTFC) for five-phase permanent-magnet synchronous motor (PMSM) with single-phase open-circuit fault (OCF) has problems such as large torque ripple, difficult setting weight coefficient, large iterative calculation of cost function, and high common-mode voltage (CMV). To solve the problems, a simplified FCS-MPTFC strategy is proposed in this paper. First, the mathematical model of five-phase PMSM with single-phase OCF is built, and the mechanism of CMV generation is analyzed. Then, the equal amplitude virtual voltage vector (V
3) is synthesized based on the principle of suppressing the third harmonic current, and the cost function of torque and flux was equivalently transformed into a voltage cost function. Meanwhile, the reference voltage vectors are calculated based on deadbeat control principle, and then the optimal V
3 is directly obtained by re-dividing sectors. Finally, to reduce the CMV under OCF, two base voltage vectors in the opposite direction are selected to replace the zero vector. Simulation and experimental results are presented to demonstrate that the proposed control strategy not only suppresses the fluctuating torque caused by single-phase open-circuit fault, but also reduces computational complexity and CMV, and restrains current harmonic. Furthermore, it exhibits excellent steady-state and dynamic performance.