Stator and Rotor Design for Multiphase Induction Machines with Pole-Changing Capability

Inhalt:
Multiphase induction machines (MIMs) with pole-switching capability represent a significant advancement in electric machine design, offering flexibility and efficiency by combining the advantages of multiphase systems, such as improved fault tolerance and reduced torque ripple, with the ability to dynamically switch magnetic pole counts. An enabler of this technology is pole-phase modulation (PPM), an electronic pole-changing technique that adjusts both the magnetic pole count and electrical phase count through adjustments in the power electronics. This paper provides detailed guidelines for designing MIMs with PPM, covering fundamental principles, design constraints, and implementation considerations. The role of stator winding design is emphasized, including configurations for phase belts, winding pole-pair counts, and harmonic components. Constraints imposed by inverter design, such as the need for high-leg-count inverters, as well as rotorbar- count considerations to avoid magnetic imbalances, vibrations, and startup issues, are examined. The paper outlines equations and methodologies for optimizing winding factors, achieving balanced magnetic circuits, and minimizing torque ripple. Methods for evaluating rotor and winding designs are presented to ensure feasible and efficient machine configurations. The provided insights allow for systematic optimization of MIMs for specific operational needs while addressing potential challenges, such as complexities in inverter and rotor designs. This paper serves as a comprehensive guide for the development of MIMs with PPM, enabling their application in diverse fields, including automotive systems, renewable energy, and industrial drives.