Two magnetless double-rotor (DR) dual-mode machines, namely the DR DCexcited multi-tooth switched reluctance (DR-DC-MSR) machine and the DR flux-switching DC (DR-FS-DC) machine, are proposed for special direct-drive applications where two rotating bodies are required to operate independently. Both machines can offer two different operation modes, namely the doubly-salient DC (DSDC) mode and MSR mode, normal and fault-tolerant operations, respectively. With the independent armature windings, both machines are able to couple their two rotors with two rotating bodies operating at various speeds. The proposed machines are designed and analyzed by using the time-stepping finite element method (TS-FEM). The simulation results confirm the validity of the proposed machines.
2. Chau, K.-T., W. Li, and C. H. T. Lee, "Challenges and opportunities of electric machines for renewable energy," Progress In Electromagnetics Research B, Vol. 42, 45-74, 2012.
3. Liu, C., K. T. Chau, and Z. Zhang, "Novel design of double-stator single-rotor magnetic-geared machines," IEEE Transactions on Magnetics, Vol. 48, No. 11, 4180-4183, November 2012.
4. Chau, K. T., C. C. Chan, and C. Liu, "Overview of permanentmagnet brushless drives for electric and hybrid electric vehicles," IEEE Transactions on Industrial Electronics, Vol. 55, No. 6, 2246-2257, June 2008.
5. Zhang, J., M. Cheng, Z. Chen, and W. Hua, "Comparison of stator-mounted permanent-magnet machines based on a general power equation," IEEE Transactions on Energy Conversion, Vol. 24, No. 4, 826-834, December 2009.
6. Liu, C., K. T. Chau, J. Zhong, W. Li, and F. Li, "Quantitative comparison of double-stator permanent magnet vernier machines with and without HTS bulk," IEEE Transactions on Applied Superconductivity, Vol. 22, No. 3, 5202405, June 2012.
7. Zhu, Z. Q., "Switched flux permanent magnet machines --- Innovation continues," International Conference on Electrical Machines and Systems, 1-10, August 2011.
8. Kawamura, A., N. Hoshi, T. W. Kim, T. Yokoyama, and T. Kume, "Analysis of anti-directional-twin-rotary motor drive characteristics for electric vehicles," IEEE Transactions on Industrial Electronics, Vol. 44, No. 1, 64-70, February 1997.
9. Hoeijmakers, M. J. and J. A. Ferreria, "The electric variable transmission," IEEE Transactions on Industry Applications, Vol. 42, No. 4, 1092-1100, July 2006.
10. Liu, C. and K.-T. Chau, "Electromagnetic design and analysis of double-rotor flux-modulated permanent-magnet machines," Progress In Electromagnetics Research, Vol. 131, 81-97, 2012.
11. Booker, J. D., P. H. Mellor, R.Wrobel, and D. Drury, "A compact, high efficiency contra-rotating generator suitable for wind turbines in the urban environment," Renewable Energy, Vol. 35, No. 9, 2027-2033, September 2010.
12. Faiz, J., J. W. Finch, and H. M. B. Metwally, "A novel switched reluctance motor with multiple teeth per stator pole and comparison of such motors," Electric Power Systems Research, Vol. 34, No. 3, 197-203, September 1995.
13. Lee, C. H. T., K. T. Chau, C. Liu, D. Wu, and S. Gao, "Quantitative comparison and analysis of magnetless machines with reluctance topologies," IEEE Transactions on Magnetics, Vol. 49, No. 7, 3969-3972, July 2013.
14. Lee, C. H. T., K. T. Chau, and C. Liu, "Design and analysis of a DC field multitooth switched reluctance machine by using soft-magnetic-composite material," International Symposium on Industrial Electronics, TD-00124, May 2013.
15. Wang, Y., J. Sun, Z. Zou, and K. T. Chau, "Design and analysis of a HTS flux-switching machine for wind energy conversion," IEEE Transactions on Applied Superconductivity, Vol. 23, No. 3, 5000904, June 2013.
16. Chen, J. T., Z. Q. Zhu, and D. Howe, "Stator and rotor pole combination for multi-tooth flux-switching permanent-magnet brushless AC machines," IEEE Transactions on Magnetics, Vol. 44, No. 12, 4659-4667, December 2008.
17. Cao, R., C. Mi, and M. Cheng, "Quantitative comparison of flux-switching permanent-magnet motors with interior permanent magnet motor for EV, HEV, and PHEV applications," IEEE Transactions on Magnetics, Vol. 48, No. 8, 2374-2384, August 2012.
18. Yu, C. and K. T. Chau, "New fault-tolerant flux-mnemonic doubly-salient permanent-magnet motor drive," IET Electric Power Application, Vol. 5, No. 5, 393-403, December 2009.
19. Cheng, M., K. T. Chau, and C. C. Chan, "Static characteristics of a new doubly salient permanent magnet motor," IEEE Transactions on Energy Conversion, Vol. 16, No. 1, March 20-25, 2001.
20. Liu, C., K. T. Chau, and J. Z. Jiang, "A permanent-magnet hybrid brushless integrated- starter-generator for hybrid electric vehicles," IEEE Transactions on Industrial Electronics, Vol. 57, No. 12, 4055-4064, December 2010.
21. Zhao, W., M. Cheng, W. Hua, H. Jia, and R. Cao, "Back-EMF harmonic analysis and fault-tolerant control of flux-switching permanent-magnet machine with redundancy," IEEE Transactions on Industrial Electronics, Vol. 58, No. 5, 1926-1935, May 2011.
22. Li, W. and K.-T. Chau, "Analytical field for linear tubular magnetic gears using equivalent anisotropic magnetic permeability," Progress In Electromagnetics Research, Vol. 127, 155-171, 2012.
23. Wang, Y., K. T. Chau, C. C. Chan, and J. Z. Zhang, "Transient analysis of a new outer-rotor permanent-magnet brushless dc drive using circuit-field-torque time-stepping finite element method," IEEE Transactions on Magnetics, Vol. 38, No. 2, 1297-1300, March 2002.
24. Salon, S. J., Finite Element Analysis of Electrical Machines, Kluwer Academic Publishers, Boston, USA, 1995.
25. Niu, S., S. L. Ho, W. N. Fu, and J. Zhu, "Eddy current reduction in high-speed machines and eddy current loss analysis with multislice time-stepping finite-element method," IEEE Transaction on Magnetics, Vol. 48, No. 2, 1007-1010, February 2012.
26. Zhao, W., M. Cheng, R. Cao, and J. Li, "Experimental comparison of remedial single-channel operations for redundant flux-switching permanent-magnet motor drive," Progress In Electromagnetics Research, Vol. 123, 189-204, 2012.