Modelling, simulation and test of direct torque-controlled multi-phase synchronous propulsion motor drives

This paper presents the analysis, simulation, and modeling of direct torque-controlled three-level inverter-fed multi-phase synchronous motor. Based on the mathematic model, a improved direct torque control scheme is proposed for three-level inverter-fed 12-phase synchronous motor. In the proposed scheme, we can control the torque and flux linkage with composed space vectors in each control period, which improves the operation performance of DTC greatly. Furthermore, this scheme optimizes the selection of the vectors and simplifies the control process. The simulations and test results are also presented