A Universal Lookup Table-Based Direct Torque Control for OW-PMSM Drives

For open-winding permanent magnet synchronous motor (OW-PMSM) system with two isolated dc voltage sources, the distribution of voltage vectors (VVs) is different under different dc-link voltage ratios. In this letter, a universal lookup table (LUT) based direct torque control (DTC) strategy is proposed for OW-PMSM drives under different conditions of the dc-link voltage ratio. The distribution criterion of VVs under various dc-link voltage ratios is analyzed and the VVs are assigned to different regions by designing a generalized region division scheme. A universal LUT is established to realize the selection of required VV in the DTC strategy. Experimental results validate the effectiveness of the proposed universal LUT-based DTC strategy for the OW-PMSM system with different voltage ratios.