Multiphase induction motor drives

Recent research articles mostly addressing towards multiphase inverter fed multiphase induction motors due to their redundant structure, and reliability with high fault tolerant capabilities. Benefits over the traditional three-phase motors are, by reducing the amplitude and increasing the frequency of torque pulsations, lowering the rotor harmonic current losses and dc link current harmonics. Moreover, if (one or two or three etc.,) phase of multiphase motor becomes open-circuited or faulty, still continue to run with remaining phases (minimum two winding in healthy condition), contributes the revolving flux and with minimal de-ratings. Some popular available multiphase ac motor topologies in application are: . Five-, Six(Asymmetrical or Symmetrical), Seven-Phase Induction Motor and found renowned applications in electric ship propulsion, traction (including electric and hybrid electric vehicles) and the concept of `more-electric´ aircraft. To exploit all the above benefits, this special session talk based on a novel dual three-phase open-ends winding motor (asymmetric six-phase induction machine). The power supply consists of four standard 2-level threephase VSIs having insulated dc sources to prevent circulation of zero-sequence current components. Note that the structure is easy scalable to nine, twelve or higher number of phases multiple of three. An original modulation strategy has been proposed to regulate each couple of 2-level VSIs such as a 3-level inverter, providing proper multi-level voltage waveforms for each three-phase stator winding. Furthermore, the proposed control algorithm allows total motor power to be shared among the four dc sources with three degrees of freedom, leading to a combination/extension of the power sharing principles. Further discussion will be based on redundancy of the used quad-i