This paper presents a dynamic modelling of a series of induction motors (IM) squirrel cage with different shapes of rotor deep bars taking into account the skin effect. The approach is divided into two parts. The first part consists in modelling the skin effect in a rectangular rotor deep-bar with three methods (conventional analytical method, nite element method and analysis method of circuit). These are compared (estimate of the relative error), and subsequently, generalized to more complex forms (trapezoidal, inverted, direct trapezoidal and double cage), done by using the two last methods which take into account the geometrical non-linearity of the slots. The second part consists in a dynamic modelling with variable parameters that take into account the skin effect, simulated for a series of motors with the same power (with different geometric shapes of rotor bars), to see their influence on the starting characteristics of these IM, and the results are compared and discussed.
1. Kostenko, M. and L. Piotrovski, Machines électriques, Tome II , Editions mire, Moscou, Russia, 1979.
2. Smith, A. C., R. C. Healey, and S. Williamson, "A transient induction motor model including saturation and deep bar effect," IEEE Transactions on Energy Conversion, Vol. 11, No. 1, 8-15, 1996. doi:10.1109/60.486570
3. Choudhury, Md. S. H., M. A. Uddin, Md. N. Hasan, and M. Shafiul, "Impact of skin effect for the design of a squirrel cage induction motor on its starting performances," International Journal of Engineering Science and Technology, Vol. 4, No. 1, Engg Journals Publications, 2012.
4. Boglietti, A., A. Cavagnino, and M. Lazzari, "Computational algorithms for induction motor equivalent circuit parameter determination - Part II: Skin effect and magnetizing characteristics," IEEE Transactions on Industrial Electronics, Vol. 58, No. 9, 3734-3740, 2011. doi:10.1109/TIE.2010.2084975
5. Saied, B. M. and A. J. Ali, "Determination of deep bar cage rotor induction machine parameters based on finite element approach," 2012 First National Conference for Engineering Sciences (FNCES), 1-6, IEEE, 2012.
6. Jelassi, S., R. Romary, and J. F. Brudny, "Slot design for dynamic iron loss reduction in induction machines," Progress In Electromagnetics Research B, Vol. 52, 79-97, 2013. doi:10.2528/PIERB13041507
7. Liwschitz-Garik, M., "Skin-effect bars of squirrel-cage rotors," Electrical Engineering, Vol. 70, No. 6, 504, 1954. doi:10.1109/EE.1954.6438810
8. Babb, A. S. and J. Williams, "Circuit analysis method to determination of A-C of machines conductor," AIEE Trans., Vol. 70, No. 10, 661-666, 1951.
10. Boldea, I. and S. A. Nasar, The Induction Machine Handbook, Finite Element Method Magnetics, User’s Manual, CRC Press, 2010.
11. Pusca, R., R. Romary, V. Fireteanu, and A. Ceban, "Finite element analysis and experimental study of the near-magnetic field for detection of rotor faults in induction motors," Progress In Electromagnetics Research B, Vol. 50, 37-59, 2013. doi:10.2528/PIERB13021203
12. Meeker, D. C., Finite Element Method Magnetics, User’s Manual, 2015.
13. Maddi, Z. D. Aouzellag, and T. Laddi, "Influence of the skin effect and the form of slot on the starting characteristics of induction motor squirrel cage," International Conference in Recent Advances in Mechanics, Mechatronics and Civil, Chemical and Industrial Engineering, 125-129, 2015.
14. Benecke, M., R. Doebbelin, G. Griepentrog, and A. Lindemann, "Skin effect in squirrel cage rotor bars and its consideration in simulation of non-steady-state operation of induction machines," PIERS Online, Vol. 7, No. 5, 421-425, 2011.
15. Kopilov, I. P., Calculation of the Electric Machines, Moscow, Russia, 2002.