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This study proposes an isolated on‐board integrated battery charger using an interior permanent magnet (IPM) machine with a nine‐slot/eight‐pole combination or its multiples, and equipped with a non‐overlapped fractional slot concentrated winding. The proposed winding layout comprises three three‐phase winding sets that are connected in such a way as to provide six motor terminals. Hence, a six‐phase or two three‐phase converters will be required for propulsion. Under motoring mode, the machine can be effectively regarded as a six‐phase machine, which provides a high fault‐tolerant capability, and allows for a 'limp home' mode of operation. Additionally, all magneto motive force subharmonics are eliminated, which significantly reduces the induced rotor eddy current losses, when compared with a conventional three‐phase motor having the same slot/pole combination. In battery charging mode, the winding is reconfigured, so that the machine is considered as a three‐phase to six‐phase rotating transformer. A 40 kW IPM machine is designed and simulated under different modes of operation using two‐dimensional finite element analysis to validate the proposed concept. A small‐scale prototype machine is also used for experimental validation. [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]