Electric propulsion technology based in predictive direct torque control and asymmetrical dual three-phase drives

Multiphase electric drives have been recently proposed for applications where the highest overall system reliability and power distribution per phase are required. The propulsion drive of an Electric Vehicle (EV) is one of these applications. Direct Torque Control (DTC) methods are normally used in conventional AC drives when fast electrical dynamic performance is required, like in electric propulsion drive systems. However, predictive control techniques have recently shown similar performance and easier applicability in multiphase drives. This paper deals with the use of a six-phase induction machine in the propulsion module of EVs. The utility of a predictive direct torque control scheme for the speed regulation of asymmetrical dual three-phase AC drives is analyzed. Based on the use of a predictive model of the drive, the control algorithm reduces the harmonic content of the stator current, improving the control performance. Simulation results are provided to illustrate the potential of the proposed propulsion technology.