Because of the current commutation and the double salient pole structure of bearingless switched reluctance motors (BSRMs), the torque and suspension force have large ripples when traditional current control methods are used. According to the special structure of the double stator BSRM (DSBSRM), the direct decoupling of torque and suspension force is realized. Therefore, the DSBSRM can be controlled separately as a conventional 12/8 SRM and a four-poles active magnetic bearing. In order to achieve the suppression of the torque ripple and improve the robustness of speed, a direct torque control (DTC) strategy using second order sliding mode (SOSM) speed controller is proposed. In order to achieve the suppression of the suspension force ripple and rotor displacement chattering, a direct suspension force control (DSFC) strategy is proposed as well. Then the SOSM-DT/DSFC model is established by simulink. The results of simulation show that the torque ripple, suspension force ripple and rotor radial displacements of DSBSRM can be reduced respectively. Moreover, the proposed control strategy has better robustness and dynamic performance than traditional control strategy.
1. Chiba, A., K. Kiyota, N. Hoshi, M. Takemoto, and S. Ogasawara, "Development of a rare-earth-free SR motor with high torque density for hybrid vehicles," IEEE Transactions on Energy Conversion, Vol. 30, No. 1, 175-182, Mar. 2015. doi:10.1109/TEC.2014.2343962
2. Rahman, K. M., B. Fahimi, G. Suresh, A. V. Rajarathnam, and M. Ehsani, "Advantages of switched reluctance motor applications to EV and HEV: Design and control issues," IEEE Transactions on Industry Applications, Vol. 36, No. 1, 111-121, Jan.–Feb. 2000. doi:10.1109/28.821805
3. Yang, Z., F. Shang, I. P. Brown, and M. Krishnamurthy, "Comparative study of interior permanent magnet, induction, and switched reluctance motor drives for EV and HEV applications," IEEE Transactions on Transportation Electrification, Vol. 1, No. 3, 245-254, Oct. 2015. doi:10.1109/TTE.2015.2470092
4. Chiba, A., et al., "Torque density and efficiency improvements of a switched reluctance motor without rare-earth material for hybrid vehicles," IEEE Transactions on Industry Applications, Vol. 47, No. 3, 1240-1246, May–Jun. 2011. doi:10.1109/TIA.2011.2125770
5. Krishnamurthy, M., C. S. Edrington, A. Emadi, P. Asadi, M. Ehsani, and B. Fahimi, "Making the case for applications of switched reluctance motor technology in automotive products," IEEE Transactions on Power Electronics, Vol. 21, No. 3, 659-675, May 2006. doi:10.1109/TPEL.2006.872371
6. Takemoto, M., H. Suzuki, A. Chiba, T. Fukao, and M. A. Rahman, "Improved analysis of a bearingless switched reluctance motor," IEEE Transactions on Industry Applications, Vol. 37, No. 1, 26-34, Jan.–Feb. 2001. doi:10.1109/28.903123
7. Sun, Y., Y. Yuan, and Y. Huang, "Design and analysis of bearingless flywheel motor specially for flywheel energy storage," Electronics Letters, Vol. 52, No. 1, 66-68, 2016. doi:10.1049/el.2015.2334
8. Takemoto, M., et al., "Radial force and torque of a bearingless switched reluctance motor operating in a region of magnetic saturation," IEEE Transactions on Industry Applications, Vol. 40, No. 1, 103-112, 2004. doi:10.1109/TIA.2003.821816
9. Chen, L. and W. Hofmann, "Design procedure of bearingless high-speed switched reluctance motors," 2010 International Symposium on Power Electronics Electrical Drives Automation and Motion (SPEEDAM), IEEE, 2010.
10. Wang, et al., "Design of novel bearingless switched reluctance motor," IET Electric Power Applications, Vol. 6, No. 2, 73, 2012. doi:10.1049/iet-epa.2010.0229
11. Xu, Z., "Design and analysis of a novel 12/14 hybrid pole type bearingless switched reluctance motor," IEEE International Symposium on Industrial Electronics, IEEE, 2012.
12. Yang, Y., F. Liu, and C. Liu, "A new bearingless switched reluctance motor with wide rotor pole arc," Industrial Electronics & Applications, 2014.
13. Wei, P., et al., "Design and characteristic analysis of a novel bearingless SRM with double stator," IEEE International Symposium on Industrial Electronics, 2012.
14. Reddy, P. K., D. Ronanki, and P. Parthiban, "Direct torque and flux control of switched reluctance motor with enhanced torque per ampere ratio and torque ripple reduction," Electronics Letters, Vol. 55, No. 8, 477-478, Apr. 18, 2019. doi:10.1049/el.2018.8241
15. Cao, X., J. Zhou, C. Liu, and Z. Deng, "Advanced control method for a single-winding bearinglessswitched reluctance motor to reduce torque ripple and radial displacement," IEEE Transactions on Energy Conversion, Vol. 32, No. 4, 1533-1543, Dec. 2017. doi:10.1109/TEC.2017.2719160
16. Takahashi, I. and Y. Ohmori, "High-performance direct torque control of an induction motor," IEEE Transactions on Industry Applications, Vol. 25, No. 2, 257-264, Mar.–Apr. 1989. doi:10.1109/28.25540
17. Cheok, A. D., "A new torque and flux control method for switched reluctance motor drives," IEEE Trans. Power Electronics, Vol. 17, No. 4, 543-557, 2002. doi:10.1109/TPEL.2002.800968
18. Takemoto, M., A. Chiba, and T. Fukao, "A method of determining the advanced angle of square-wave currents in a bearingless switched reluctance motor," IEEE Transactions on Industry Applications, Vol. 37, No. 6, 1702-1709, Nov.–Dec. 2001. doi:10.1109/28.968181
19. Xu, Z., D. Lee, and J. Ahn, "Comparative analysis of bearinglessswitched reluctance motors with decoupled suspending force control," IEEE Transactions on Industry Applications, Vol. 51, No. 1, 733-743, Jan.–Feb. 2015. doi:10.1109/TIA.2014.2331422
20. Cao, X., Z. Deng, G. Yang, and X. Wang, "Independent control of average torque and radial force in bearinglesss witched-reluctance motors with hybrid excitations," IEEE Transactions on Power Electronics, Vol. 24, No. 5, 1376-1385, May 2009. doi:10.1109/TPEL.2009.2016568
21. Wu, X., Y. Yang, and Z. Liu, "Analysis and control of a novel bearingless switched reluctance motor with wider rotor teeth," IECON 2017 — 43rd Annual Conference of the IEEE Industrial Electronics Society, 1796-1801, Beijing, 2017. doi:10.1109/IECON.2017.8216304
22. Ammar, A., A. Bourek, and A. Benakcha, "Nonlinear SVM-DTC for induction motor drive using input-output feedback linearization and high order sliding mode control," ISA Transactions, Vol. 67, 428-442, 2017. doi:10.1016/j.isatra.2017.01.010
23. Huangfu, Y.-G., et al., "Chattering avoidance high order sliding mode control for permanent magnet synchronous motor," Electric Machines and Control, 2012.
24. Rafiq, M., et al., "A second order sliding mode control design of a switched reluctance motor using super twisting algorithm," Simulation Modelling Practice and Theory, Vol. 25, 106-117, 2012. doi:10.1016/j.simpat.2012.03.001
25. Ro, H., H. Jeong, and K. Lee, "Torque ripple minimization of switched reluctance motor using direct torque control based on sliding mode control," 2013 IEEE International Symposium on Industrial Electronics, 1-6, Taipei, 2013.