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In electric drive applications that are based on high‐speed induction motors (IMs) with an extended speed range, stator winding pole‐changing is a possible technique to avoid oversizing the driving motor. The electronic pole changing employed in multiphase IMs has gained recent interest because it avoids physical winding reconfiguration. The effective number of poles of the air gap flux distribution can be electronically altered by simply changing the applied current sequence to a multiphase stator. The main problem associated with this technique is the significant increase in machine magnetising current with the increase in effective pole number when conventional multiphase distributed windings are employed. This study proposes a new fractional‐slot concentrated winding layout with a special stator connection suitable for pole‐amplitude modulated IMs that offers a 2:1 pole ratio while maintaining equal magnetising current for both winding pole pairs. Moreover, constant power operation can be achieved for a speed range of over 4 pu. The main concept is discussed and verified through simulations and experimentally. The machine mathematical model and the required vector space decomposition‐based controller are also presented. [ABSTRACT FROM AUTHOR]

In many applications, interior permanent magnet synchronous machines (IPMSMs) with fractional slot concentrated windings (FSCWs) are considered promising candidates in terms of higher power density and efficiency. In addition, employing a multiphase stator winding improves the drive train availability and increases reliability. This study investigates the effect of applying stator shifting to five‐phase FSCW winding IPMSMs to suppress the effect of the slot harmonics by doubling the number of slots. In this case, the winding coil pitch will be two, which stands as a compromise between single‐tooth and distributed winding topologies. This highly improves the air gap flux distribution, significantly reduces both rotor core and magnet eddy current losses, and increases saliency ratio and reluctance torque component. Moreover, an improved performance under fault conditions, in terms of lower torque ripple, and core and magnet losses, adds to the main advantages of this technique. Various slot/pole combinations suitable for five‐phase machines are investigated. A full simulation case study based on two‐dimensional finite element analysis is applied to the 20‐slot/18‐pole stator with single‐tooth winding under both healthy and open‐circuit phase fault cases. [ABSTRACT FROM AUTHOR]