DESIGN AND PERFORMANCE COMPARISON OF FOUR-POLE BRUSHLESS DC MOTORS WITH DIFFERENT POLE/SLOT COMBINATIONS

Abstract

When the design process of the brushless motor is examined, attention must be paid to the correct choice of magnet material, internal or external rotor structure and the choice of core and winding structure. In addition to all these, the number of phases, the number of rotor poles, and the choice of slots configurations depending on them also have great importance. For this reason, to achieve optimum design, it is necessary to analyze all possible designs with different pole/slot configurations that can accommodate similar power and speed expectations. In this study, three different designs have been realized with different pole/slot configurations for four-pole, internal rotor brushless DC motors, which are frequently used in many different applications today. Designed motors have been analyzed with Finite Element Method to obtain the cogging torque, efficiency and active material costs. All motors that are analyzed have 100 W, 3000 rpm, 4/6, 4/12 and 4/15 pole/slot configurations respectively.

Keywords

• brushless DC motor,pole/slot combinations,efficiency,internal rotor

References

1. Hanselman, D. Brushless permanent magnet motor design. 2nd ed. OH: Magna Physıcs Publishing, 2006.
2. Saygın, A., Ocak, C., Dalcalı, A., Çelik, E. Optimum rotor design of small PM BLDC motor based on high efficiency criteria. ARPN Journal of Engineering and Applied Sciences 2015; 10(19): 9127-9132.
3. Bayındır, R., Ocak, C., Topaloğlu, İ. Investigation of the effect of magnet thickness on output power and torque of PM BLDC machines using parametric approach method. In Proceedings of POWERENG 2011; 11-13 May 2011; Malaga, Spain. pp. 1-4.
4. Ehsani, M., Gao, Y., Gay, S. Characterization of electric motor drives for traction applications. IECON'03. 29th Annual Conference of the IEEE Industrial Electronics Society; Roanoke, VA, USA, 2003, pp. 891-896 vol.1
5. Yuan, M., Niu, S. Design and analysis of a novel modular linear double-stator biased flux machine. IEEE Transactions on Magnetics, Early Access, 2018: 1-5.
6. Zhang, F., Yu, S., Wang, Y., Jin, S., Jovanovic, M.G. Design and performance comparisons of brushless doubly fed generators with different rotor structures. IEEE Transactions on Industrial Electronics, 2019: 66(1), 631-640. doi: 0.1109/TIE.2018.2811379
7. Carraro, E., Zhang, S., Koch, M. Design and performance comparison of fractional slot concentrated winding spoke type synchronous motors with different slot-pole combinations. IEEE Transactions on Industry Applications, 2018: 54(3), 2276-2284.
8. Jun, H.W., Seol, H.S., Lee, J. Effect of pole–slot combination on eddy-current formation in pmsm rotor assembly ıncluding retaining plate structure. IEEE Transactions on Magnetics, 2017: 53(11).

9. Zhu, Z.Q., Wu, J., Modh Jamil, M.L. Influence of pole and slot number combinations on cogging torque in permanent-magnet machines with static and rotating eccentricities. IEEE Transactions on Industry Applications, 2014: 50(5), 3265-3277.
10. Jafarishiadeh, S., Ardebili, M., Marashi, A.N. Investigation of pole and slot numbers in axial-flux pm BLDC motors with single-layer windings for electric vehicles. 24th Iranian Conference on Electrical Engineering (ICEE), 2016, Shiraz, Iran.
11. Lee, S.J., Kim, S.I., Hong, J.P. Characteristics of PM synchronous motors according to pole-slot combinations for eps applications. International Journal of Automotive Technology, 2014: 15(7), 1183−1187. doi: 10.1007/s12239-014-0123-6
12. Çelik, E., Öztürk, N. A new fuzzy logic estimator for reduction of commutation current pulsation in brushless DC motor drives with three-phase excitation. Neural Comput & Application, 2017: 1-10. doi: 10.1007/s00521-017-3083-8
13. Krishan, R. Electric motor drives: modeling, analysis and control. New Jersey: Prentice Hall, Inc. 2001.
14. Aydoğdu, Ö. Sensorless control of brushless dc motors by means of genetic based fuzzy controller. PhD Thesis, Selçuk University, Konya, Turkey 2006.
15. Hameyer, K., Belmans, R. Numerical modelling and design of electrical machines and devices. Southampton, Boston: WIT Press, 1999.
16. Dalcalı, A., Kurt, E., Çelik, E., Öztürk., N. Cogging torque reduction by using the skewing and separated magnet techniques. 6th Eur. Conf. Ren. Energy Sys., 2018: 24(6), Istanbul, Turkey.
17. Dalcalı, A., Akbaba, M. Comparison of 2D and 3D magnetic field analysis of single-phase shaded pole induction motors. Engineering Science and Technology, An International Journal, 2016: 19(1), 1–7. doi: 10.1016/j.jestch.2015.04.013
18. Ho, S. L., Fu, W. N. Review and future application of finite element methodes in induction motors. Electric Machines & Power Systems, 1998: 26 (2), 111–125.
19. Dadpour, A., Ansari, K. Conversion of shaded-pole induction motor to switched reluctance motor and effects of pole shoe and notch on SRM noise", IEEE XXXIII International Scientific Conference Electronics and Nanotechnology, 2013, Kiev.