Analytical Method for Magnetic Field and Electromagnetic Performances in Switched Reluctance Machines

  • Libing Jing
  • Jia Cheng
  • Tong BenEmail author
Original Article


This paper presents a new analytical method for the computation of magnetic field distributions and electromagnetic performances in switched reluctance machines (SRM). The proposed model is sufficiently general to be used with any number of stator slots and rotor poles with electrically excited. Due to the inherent nonlinear characteristics of SRM, the conventional analytic model has a limited accuracy which does not take into account the saturation. In order to calculate the accuracy and consider the local magnetic saturation on the stator and rotor teeth, the proposed method is based on the resolution of 2-D Laplace’s and Poisson’s equations in polar coordinates by the separation of variables technique. The solution region is divided into three types of regular subdomains, viz. air gap, stator slots and rotor slots. Magnetic field distributions, flux linkage, self-inductance, mutual inductance and static electromagnetic torque computed with the proposed analytical method are validated through finite-element method.


Magnetic field Analytical method Electromagnetic torque SRM FEM 



This work was supported by National Natural Science Foundation of China (Project No. 51707072) and Applied Basic Research Project of Yichang (Project No. A19-402-a03).


  1. 1.
    Madhavan R, Fernandes BG (2013) Axial flux segmented SRM with a higher number of rotor segments for electric vehicles. IEEE Trans Energy Convers 28:203–213CrossRefGoogle Scholar
  2. 2.
    Chiba A, Kiyota K, Hoshi N, Takemoto M, Ogasawara S (2015) Development of a rare-earth-free SR motor with high torque density for hybrid vehicles. IEEE Trans Energy Convers 30:175–182CrossRefGoogle Scholar
  3. 3.
    Fahimi B, Emadi A, Sepe RB (2004) A switched reluctance machine-based starter/alternator for more electric cars. IEEE Trans Energy Convers 19:116–124CrossRefGoogle Scholar
  4. 4.
    Cheng H, Chen H, Yang Z (2015) Design indicators and structure optimization of switched reluctance machine for electric vehicles. IET Elect Power Appl 9(4):319–331CrossRefGoogle Scholar
  5. 5.
    Takeno M, Chiba A, Hoshi N, Ogasawara S, Takemoto M, Rahman MA (2012) Test results and torque improvement of the 50-kw switched reluctance motor designed for hybrid electric vehicles. IEEE Trans Ind Appl 48(4):1327–1334CrossRefGoogle Scholar
  6. 6.
    Michon M, Calverley SD, Atallah K (2012) Operating strategies of switched reluctance machines for exhaust gas energy recovery systems. IEEE Trans Ind Appl 48(5):1478–1486CrossRefGoogle Scholar
  7. 7.
    Li G, Ojeda J, Hlioui S, Hoang E, Lecrivain M, Gabsi M (2012) Modification in rotor pole geometry of mutually coupled switched reluctance machine for torque ripple mitigating. IEEE Trans Magn 48(6):2025–2034CrossRefGoogle Scholar
  8. 8.
    Husain I (2002) Minimization of torque ripple in SRM drives. IEEE Trans Ind Electron 49:28–39CrossRefGoogle Scholar
  9. 9.
    Sahin C, Amac AE, Karacor M, Emadi A (2012) Reducing torque ripple of switched reluctance machines by relocation of rotor moulding clinches. IET Elect Power Appl 6(9):753–760CrossRefGoogle Scholar
  10. 10.
    Vandana R, Fernandes BG (2015) Design methodology for high-performance segmented rotor switched reluctance motors. IEEE Trans Energy Convers 30(1):11–21CrossRefGoogle Scholar
  11. 11.
    Zhu ZQ, Lee B, Huang L, Chu W (2017) Contribution of current harmonics to average torque and torque ripple in switched reluctance machines. IEEE Trans Magn 53(3):1–9Google Scholar
  12. 12.
    Dowlatshahi M, Nejad SMS, Ahn JW (2013) Torque ripple minimization of switched reluctance motor using modified torque sharing function. In: Proc. IEEE Iranian Conf. Elect. Eng., Mashhad, Iran, pp 1–6Google Scholar
  13. 13.
    Cao X, Zhou JX, Liu CY, Deng ZQ (2017) Advanced control method for single-winding bearingless switched reluctance motor to reduce torque ripple and radial displacement. IEEE Trans Energy Convers 32(4):1533–1543CrossRefGoogle Scholar
  14. 14.
    Fu J, Zhu C (2012) Subdomain model for predicting magnetic field in slotted surface mounted permanent-magnet machines with rotor eccentricity. IEEE Trans Magn 48(5):1906–1917CrossRefGoogle Scholar
  15. 15.
    Alam FR, Abbaszadeh K (2016) Magnetic field analysis in eccentric surface-mounted permanent-magnet motors using an improved conformal mapping method. IEEE Trans Energy Convers 31(1):333–334CrossRefGoogle Scholar
  16. 16.
    Qian H, Guo H, Wu ZY, Ding XF (2014) Analytical solution for cogging torque in surface-mounted permanent-magnet motors with magnet imperfections and rotor eccentricity. IEEE Trans Magn 50(8):1–15CrossRefGoogle Scholar
  17. 17.
    Pina AJ, Subhra P, Rakib I, Xu LY (2015) Effect of manufacturing variations on cogging torque in surface-mounted permanent magnet motors. In: 2015 IEEE Energy Conversion Congress and Exposition (ECCE), pp 4843–4850Google Scholar
  18. 18.
    Qiu ZJ, Dai J, Yang J, Zhou XY, Zhang YJ (2015) Research on rotor eccentricity compensation control for bearing less surface-mounted permanent-magnet motors based on an exact analytical method. IEEE Trans Magn 51(11):1–4Google Scholar
  19. 19.
    Radun A (1999) Analytical calculation of the switched reluctance motor’s unaligned inductance. IEEE Trans Magn 35(6):4473–4481CrossRefGoogle Scholar
  20. 20.
    Khedda ZD, Boughrara K, Dubas F, Ibtiouen R (2017) Nonlinear analytical prediction of magnetic field and electromagnetic performances in switched reluctance machines. IEEE Trans Magn 53(7):8107311Google Scholar
  21. 21.
    Boughrara K, Lubin T, Ibtiouen R (2013) General subdomain model for predicting magnetic field in internal and external rotor multiphase flux-switching machines topologies. IEEE Trans Magn 49(10):5310–5325CrossRefGoogle Scholar

Copyright information

© The Korean Institute of Electrical Engineers 2019

Authors and Affiliations

  1. 1.Hubei Micro-grid Engineering Technology Research CenterChina Three Gorges UniversityYichangChina
  2. 2.College of Electrical Engineering and New EnergyChina Three Gorges UniversityYichangChina

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