Calculation of Airgap Function and Inductance in Fractional-Slot Concentrated-Wound Interior Permanent Magnet Machines

  • Mohammad Farshadnia
Part of the Springer Theses book series (Springer Theses)


This chapter deals with analytical modelling of the equivalent airgap function in a FSCW IPM machine which is later used for calculation of the inductances and the stator flux density in the airgap. The conventional equivalent airgap function is first introduced. A novel equivalent airgap function is then proposed that is based on the specific characteristics of an FSCW stator and the analytical model of the non-homogeneous magnetic saturation of the rotor iron that was previously proposed in Chapter 4. The inductances of the machine and the stator flux density in the airgap are then analytically calculated using the proposed equivalent airgap function and the MMF obtained in Chapter 2. The results are validated through a case-study using FEA and experimental measurements of the prototype FSCW IPM machine.


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© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.School of Electrical Engineering and TelecommunicationsThe University of New South WalesSydneyAustralia

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