Samer Saleh Hakami and Kyo-Beum Lee, "Enhanced Predictive Torque Control for Three-Level NPC Inverter-Fed PMSM Drives Based on Optimal Voltage Magnitude Control Method," IEEE Transactions on Power Electronics, vol. 38, no. 3, pp. 3725-3738, Mar. 2023. -SC > Paper

The major drawback of conventional predictive torque control (PTC) is that it fixes the magnitude of the reference voltage vector (VV) to 70 %. This 

limitation results in large torque and flux ripples and slow dynamic response, especially when the permanent magnet synchronous motor (PMSM) 

operates in low-speed regions. A promising approach for reducing torque and flux ripples is by replacing the two-level inverter with a three-level 

neutral-point-clamped (NPC) inverter. Nevertheless, because of the elimination of zero VV during torque decrement in a conventional PTC, a large 

torque ripple appears in the low-speed region. In addition, high-speed operation is not applicable unless more DC-link is injected. To solve these 

problems, an effective, creative, and low-complex PTC based on a reference voltage vector magnitude control method (RVVCM) is proposed in this 

study. The proposed PTC effectively minimizes torque and flux ripples by utilizing only the required magnitude of reference VV of the three-level NPC 

inverter based on the variable voltage control concept. Furthermore, the dynamic response of the torque is improved by applying the full magnitude

of applied VV. Simulation and experimental results are presented to validate the effectiveness of the proposed RVVCM-based PTC algorithm.