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This paper studies and proposes the vector space decomposition-based direct torque control (DTC) scheme for the T-type neutral-point-clamping (T-NPC) three-level inverters-fed double-stator-winding permanent magnet synchronous machine (PMSM) drive, which provides an effective solution for high-power high-reliability applications. The key is to propose a simple but effective space vector modulation (SVM) for DTC of T-NPC double-stator-winding drives-based two-step voltage vector synthesis, in such a way that good dynamic response and harmonic performance are obtained. The closed-loop controllers on harmonic subspace are incorporated to suppress the possible harmonics induced from back electromotive force and unbalanced parameters in phase windings of electrical machine. Furthermore, a hybrid current control is proposed for fault-tolerant operation of the T-NPC double-stator-winding PMSM drives under one-phase open-circuit conditions. In the hybrid current controller, the healthy winding still uses the SVM-DTC control while the faulty winding uses the closed-loop current controller to track the optimized current references. Both simulation and experimental results are presented to verify the performance of the proposed switching strategies and control schemes. [ABSTRACT FROM AUTHOR]

In this article, a dual-vector located model predictive control (DL-MPC) method based on a single dc-link current sensor is proposed for the permanent-magnet linear motor drive system. In DL-MPC, the phase currents are reconstructed by sampled dc-link current and selected active voltage vector (VV). Meanwhile, the sunk number of phase current is defined to evaluate the accuracy of current reconstruction. The first-optimal and second-optimal VVs are determined by dual-vector location. The second-optimal VV is selected for the voltage source inverter when the sunk number exceeds the threshold. Compared with traditional MPC schemes, DL-MPC has smaller current tracking error and better dynamic performance. Meanwhile, DL-MPC has more accurate current reconstruction and lower computation burden than that of the traditional MPC. The effectiveness of DL-MPC is verified by both theoretical analysis and experimental results. [ABSTRACT FROM AUTHOR]