Ibrahim Mohd Alsofyani and Kyo-Beum Lee, "Three-Level Inverter-Fed Model Predictive Torque Control of a Permanent Magnet Synchronous Motor with Discrete Space Vector Modulation and Simplified Neutral-Point Voltage Balancing," Journal of Power Electronics, > Paper

In this paper, discrete space vector modulation (DSVM) is used to achieve flux and torque ripple reduction for the steady-state operation of finite set-model predictive torque control (FS-MPTC) of a three-level neutral-point-clamped inverter (3L-NPCI). In the proposed DSVM, the synthesis of voltage vectors (VVs) can be controlled and implemented online eliminating the requirement of a VV look-up table. In addition, a simple and efficient preselection VV strategy is presented to reduce the number of candidate VVs in the prediction stage. The problem of capacitor voltage imbalance in 3L-NPCI is easily solved without including it as a control objective in the cost function. Thus, the complexity of tuning multiple weighting factors can be reduced. Hence, the proposed PTC-DSVM algorithm is simple and is capable of minimizing torque/flux ripples and achieving a fast torque dynamic performance in a permanent magnet synchronous motor while mainlining balanced capacitor voltages. The effectiveness of the proposed method was verified through experimental results.