Skip to main content
Log in

Time-stepping finite element analysis on the influence of skewed rotors and different skew angles on the losses of squirrel cage asynchronous motors

  • Published:
Science China Technological Sciences Aims and scope Submit manuscript

Abstract

To study the influence of skewed rotors and different skew angles on the losses of squirrel cage asynchronous motors, a 5.5-kW motor was taken as an example and the multi-sliced field-circuit coupled time stepping finite element method (T-S FEM) was used to analyze the axially non-uniform fundamental and harmonic field distribution characteristics at typical locations in the stator and rotor cores. The major conclusions are: firstly the skewed rotor exhibits a decrease in the harmonic copper losses caused by slot harmonic currents in the stator winding and rotor bars. Secondly, the skewed rotor shifts the non-uniform distribution of field in the axial direction, which leads to more severe saturation and an increase in iron losses. The heavier the load, the more pronounced the increase in iron losses. Furthermore, the influences of different skew angles on motor losses are studied systematically, with skew angles from 0.5 to 1.5 stator tooth pitch. It is found that the lowest total loss occurs at 0.8 stator tooth pitch, and the slot harmonics can be decreased effectively.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Chen S K. Electrical Machines Design (in Chinese). Beijing: China Machines Press, 2008. 275–277

  2. Williamson S, Flack T J, Volschenk A F. Representation of skew in time-stepped two-dimensional finite-element models of electrical machines. IEEE Trans Ind Appl, 1995, 31(5): 1009–1015

    Article  Google Scholar 

  3. Jiang J Z, Fu W N. Multi-slice finite element analysis of skewed induction motors (in Chinese). Trans China Electrotech Soc, 1997, 12(5): 11–17

    Google Scholar 

  4. Urresty J C, Riba J R, Romeral L, et al. A Simple 2-D finite-element geometry for analyzing surface-mounted synchronous machines with skewed rotor magnets. IEEE Trans Magn, 2010, 46(11): 3948–3954

    Article  Google Scholar 

  5. Gyselinck J J C, Vandevelde L, Melkebeek J A A. Multi-slice FE modeling of electrical machines with skewed slots-The skew discretization error. IEEE Trans Magn, 2001, 37(5): 3233–3237

    Article  Google Scholar 

  6. Kawase Y, Yamaguchi T, Tu Z P, et al. Effects of skew angle of rotor in squirrel-cage induction motor on torque and loss characteristics. IEEE Trans Magn, 2009, 45(3): 1700–1703

    Article  Google Scholar 

  7. McClay C I, Williamson S. The variation of cage motor losses with skew. IEEE Trans Ind Appl, 2000, 36(6): 1563–1570

    Article  Google Scholar 

  8. McClay C I, Williamson S. Influence of rotor skew on cage motor losses. IEE Elect Power Appl, 1998, 145(5): 414–422

    Article  Google Scholar 

  9. Kown B I, Kim B T, Jun C S. Analysis of axially non-uniform loss distribution in 3-phase induction motor considering skew effect. IEEE Trans Magn, 1999, 35(3): 1298–1301

    Article  Google Scholar 

  10. Kalokiris G D, Kefalas T D, Kladas A G, et al. Special air-gap element for 2-D FEM analysis of electrical Machines accounting for rotor skew. IEEE Trans Magn, 2005, 41(5): 2020–2023

    Article  Google Scholar 

  11. Dorrell D G, Holik P J, Rasmussen C B. Analysis and effects of inter-bar current and skew on a long skewed-rotor induction motor for pump applications. IEEE Trans Magn, 2007, 43(6): 2534–2536

    Article  Google Scholar 

  12. Dorrell D G, Holik P J, Lombard P, et al. A Multisliced finite-element model for induction machines incorporating interbar current. IEEE Trans Ind Appl, 2009, 45(1): 131–141

    Article  Google Scholar 

  13. Zhao H S, Luo Y L, Liu X F, et al. Analysis on no-load iron losses distribution of asynchronous motors with time-stepping finite element method (in Chinese). Proc CSEE, 2010, 30(30): 99–106

    Google Scholar 

  14. Zhao H S, Liu X F, Hu J, et al. The influence of wye and delta connection on induction motor losses taking slot opening and skew effect into account. IEEE IEMDC, Miami, USA, 2009. 213–218

  15. Zhao H S, Liu X F, Luo Y L, et al. Losses characteristics of cage induction motors under voltage deviation conditions (in Chinese). Electric Mach Contl, 2010, 14(5): 13–19

    Google Scholar 

  16. Bertotti G. General properties of power losses in soft ferromagnetic material. IEEE Trans Magn, 1988, 24(1), 621–630

    Article  Google Scholar 

  17. Cheng S K, Pei Y L, Zhang P, et al. Fundamental research on the third function of rotating electric machine. Trans China Electrotech Soc, 2007, 22(7): 12–17

    Google Scholar 

  18. National Rotational Electrical Machines Standardization Technical Committee. GB/T 1032-2005. Test procedures for three-phase induction motors (in Chinese). Beijing: Standard Press of China, 2005. 6–7

    Google Scholar 

  19. Cui X S, Luo Y L, Yang Y L, et al. Energy saving theory and approach for asynchronous motor under the periodically variable running condition (in Chinese). Proc CSEE, 2008, 28(18): 90–97

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to HaiSen Zhao.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Zhao, H., Liu, X., Luo, Y. et al. Time-stepping finite element analysis on the influence of skewed rotors and different skew angles on the losses of squirrel cage asynchronous motors. Sci. China Technol. Sci. 54, 2511–2519 (2011). https://doi.org/10.1007/s11431-011-4433-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11431-011-4433-x

Keywords

Navigation