1. Department of Electrical Engineering Southern Taiwan University Robot and Servo Drive Lab. Commutation Control for the Low-Commutation Torque Ripple in the Position Sensorless Drive of the Low-Voltage Brushless DC Motor Sang-Yong Jung, Member, IEEE, Yong-Jae Kim, Member, IEEE, Jungmoon Jae, and Jaehong Kim, Member, IEEE IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 29, NO. 11, NOVEMBER 2014 2016/1/17 學生 : 蔡澤銘 指導教授 : 王明賢

2. Department of Electrical Engineering Southern Taiwan University outline Abstract Introduction Phase advancing and overlapping control Phase advancing and overlapping control of the low voltage sensorless BLDC motor drive Experiment results Conclusion 2016/1/17 Robot and Servo Drive Lab. 2

3. Department of Electrical Engineering Southern Taiwan University Abstract This paper discusses a commutation control method aimed at reducing the commutation torque ripple in sensorless drive of brushless direct current. In order to minimize torque ripple for the entire speed range, a comprehensive analysis of commutation torque ripple was made according to three commutation control methods. 2016/1/17 Robot and Servo Drive Lab. 3

4. Department of Electrical Engineering Southern Taiwan University Introduction A hysteresis and deadbeat current control have been proposed to minimize the commutation torque ripple, both methods use inner current control loops to regulate commutation current. Conventional six-step and phase advancing (PA) methods are adopted below the base speed, and the phase-advancing with overlapping (PAO) method is used for over the base speed to obtain higher speed operation with low torque ripple. 2016/1/17 Robot and Servo Drive Lab. 4

5. Department of Electrical Engineering Southern Taiwan University System configuration 2016/1/17 Robot and Servo Drive Lab. 5

6. Department of Electrical Engineering Southern Taiwan University Single loop control configuration 2016/1/17 Robot and Servo Drive Lab. 6

7. Department of Electrical Engineering Southern Taiwan University Phase advancing and overlapping control The PA technique, which is quite similar to the conventional field-weakening control in the SM-PMSM drive above the base speed, is a good solution to obtain a wider speed range That is the case of θou = θol > 0. Therefore, the magnitude of the commutation torque ripple reduces with PA when θou = θol ∈ [0, π/6]. Another approach to obtain a wider speed range is the socalled overlapping method that increases the conduction period over 120 ◦, i.e., 150 ◦ or 180 ◦. That is the case of θou > 0 and θol = 0. 2016/1/17 Robot and Servo Drive Lab. 7

8. Department of Electrical Engineering Southern Taiwan University Analysis of the commutation torque ripple 2016/1/17 Robot and Servo Drive Lab. 8

9. Department of Electrical Engineering Southern Taiwan University Modeling of the commutation From the assumptions of symmetrical windings, general voltage equations for the three-phase BLDC motor are 2016/1/17 Robot and Servo Drive Lab. 9

10. Department of Electrical Engineering Southern Taiwan University Waveforms of phase currents 2016/1/17 Robot and Servo Drive Lab. 10

11. Department of Electrical Engineering Southern Taiwan University 2016/1/17 Robot and Servo Drive Lab. 11

12. Department of Electrical Engineering Southern Taiwan University Equivalent circuit of period 2016/1/17 Robot and Servo Drive Lab. 12

13. Department of Electrical Engineering Southern Taiwan University From Figs. 4 and 5, voltage equations, (1)−(3), during the commutation period are represented in the state space form as 2016/1/17 Robot and Servo Drive Lab. 13

14. Department of Electrical Engineering Southern Taiwan University From (7)−(9), the offset voltage, vsn, is calculated as where Ia1 = ia (t1 ). Thus, the total torque variation caused by the commutation current is calculated as 2016/1/17 Robot and Servo Drive Lab. 14

15. Department of Electrical Engineering Southern Taiwan University Magnitude of the commutation torque ripple calculated 2016/1/17 Robot and Servo Drive Lab. 15

16. Department of Electrical Engineering Southern Taiwan University Magnitude of the commutation torque ripple calculated 2016/1/17 Robot and Servo Drive Lab. 16

17. Department of Electrical Engineering Southern Taiwan University Magnitude of the commutation torque ripple calculated 2016/1/17 Robot and Servo Drive Lab. 17

18. Department of Electrical Engineering Southern Taiwan University Simulation and experimental results 2016/1/17 Robot and Servo Drive Lab. 18

19. Department of Electrical Engineering Southern Taiwan University 2016/1/17 Robot and Servo Drive Lab. 19

20. Department of Electrical Engineering Southern Taiwan University Pole voltage and phase current 2016/1/17 Robot and Servo Drive Lab. 20

21. Department of Electrical Engineering Southern Taiwan University Pole voltage and phase current 2016/1/17 Robot and Servo Drive Lab. 21

22. Department of Electrical Engineering Southern Taiwan University Pole voltage and phase current 2016/1/17 Robot and Servo Drive Lab. 22

23. Department of Electrical Engineering Southern Taiwan University Measured torque waveform 2016/1/17 Robot and Servo Drive Lab. 23

24. Department of Electrical Engineering Southern Taiwan University Measured torque waveform 2016/1/17 Robot and Servo Drive Lab. 24

25. Department of Electrical Engineering Southern Taiwan University Measured torque waveform 2016/1/17 Robot and Servo Drive Lab. 25

26. Department of Electrical Engineering Southern Taiwan University Torque ripples compare 2016/1/17 Robot and Servo Drive Lab. 26

27. Department of Electrical Engineering Southern Taiwan University Maximum speed PAO 2016/1/17 Robot and Servo Drive Lab. 27

28. Department of Electrical Engineering Southern Taiwan University Conclusion In order to minimize the torque ripple through the entire speed range, a comprehensive analysis of the commutation torque ripple was made depending on common three commutation control methods. The proposed sensorless drive method for the low torque ripple was implemented for automotive fan applications. 2016/1/17 Robot and Servo Drive Lab. 28

29. Department of Electrical Engineering Southern Taiwan University References [1] H. R. Bolton and R. A. Ashen, “Influence of motor design and feedcurrent waveform on torque ripple in brushless DC drives,” IEE Proc. Electr. Power Appl., vol. 131, no. 3, pp. 82–90, May 1984. [2] Y. Murai, Y. Kawase, K. Ohashi, K. Nagatake, and K. Okuyama, “Torque ripple improvement for brushless DCminiature motors,” IEEE Trans. Ind. Appl., vol. 25, no. 3, pp. 441–450, May/Jun. 1989. [3] R. Carlson, M. L. -Mazenc, and J. C. dos S. Fagundes, “Analysis of torque ripple due to phase commutation in brushless DC machines,” IEEE Trans. Ind. Appl., vol. 28, no. 3, pp. 632–638, May/Jun. 1992. [4] J. S. Lawler, J. M. Bailey, J. W. McKeever, and J. Pinto, “Limitation of the conventional phase advance method for constant power operation of the brushless DC motor,” in Proc. IEEE SoutheastCon, 2002, pp. 174–180. [5] S. Jianwen, D. Nolan, M. Teissier, and D. Swanson, “A novel microcontoller- based sensorless brushless DC (BLDC) motor drive for automotive fuel pumps,” IEEE Trans. Ind. Appl., vol. 39, no. 6, pp. 1734–1740, Nov./Dec. 2003. 2016/1/17 Robot and Servo Drive Lab. 29

30. Department of Electrical Engineering Southern Taiwan University [6] W. Chang-hee, S. Joong-Ho, and I. Choy, “Commutation torque ripple reduction in brushless DC motor drives using a single DC current sensor,” IEEE Trans. Power Electron., vol. 19, no. 2, pp. 985–990, Mar. 2004. [7] T. -H. Kim and M. Ehsani, “Sensorless control of the BLDC motors from near- zero to high speeds,” IEEE Trans. Power Electron., vol. 6, no. 6, pp. 1635–1645, Nov. 2004. [8] G. H. Jang and M. G. Kim, “Optimal commutation of a BLDC motor by utilizing the symmetric terminal voltage,” IEEE Trans. Magn., vol. 42, no. 10, pp. 3473–3475, Oct. 2006. [9] D.-K. Kim, K.-W. Lee, and B. I. Kwon, “Commutation torque ripple reduction in a position sensorless brushless DC motor drive,” IEEE Trans. Power Electron., vol. 21, no. 6, pp. 1762–1768, Nov. 2006. [10] Z. Xiaofeng and L. Zhengyu, “A newBLDCmotor drives method based on buck converter for torque ripple reduction,” in Proc. IEEE Power Electron. Motion Contr., Conf., 2006, pp. 1–4. 2016/1/17 Robot and Servo Drive Lab. 30

31. Department of Electrical Engineering Southern Taiwan University [11] Y. Liu, Z. Q. Zhu, and D. Howe, “Commutation-torque-ripple minimization in direct-torque-controlled PM brushless DC drives,” IEEE Trans. Ind. Appl., vol. 43, no. 4, pp. 1012–1021, Jul./Aug. 2007. [12] W. Chen, C. Xia, and M. Xue, “A torque ripple suppression circuit for brushless DC motors based on power DC/DC converters,” in Proc. IEEE Ind. Electron. Appl. Conf., 2008, pp. 1453–1457. [13] H. S. Chuang, Y.-L. Ke, and Y. C. Chuang, “Analysis of commutation torque ripple using different PWM modes in BLDC motors,” in Proc. IEEE Proc. Ind. Commerc. Power Syst. Tech. Conf., 2009, pp. 1–6. [14] R. Krishnan, Permanent Magnet Synchronous and Brushless dc Motor Drives. Boca Raton, FL, USA: CRC Press, 2010, chs. 9–13. [15] S. B. Ozturk, W. C. Alexander, and H. A. Toliyat, “Direct torque control of four-switch brushless DC motor with non-sinusoidal back EMF,” IEEE Trans. Power electron., vol. 25, no. 2, pp. 263–271, Feb. 2010. 2016/1/17 Robot and Servo Drive Lab. 31

32. Department of Electrical Engineering Southern Taiwan University [16] C.-L. Chiu, Y.-T. Chen, Y.-L. Liang, and R.-H. Liang, “Optimal driving efficiency design for the single-phase brushless DC fan motor,” IEEE Trans. Magn., vol. 46, no. 4, pp. 1123–1130, Apr. 2010. [17] T. Shi, Y. Guo, P. Song, and C. Xia, “A new approach of minimizing commutation torque ripple for brushless DC motor based on DC-DC converter,” IEEE Trans. Ind. Electron., vol. 57, no. 10, pp. 3483–3490, Oct. 2010. [18] F. Aghili, “Fault-tolerant torque control of BLDC motors,” IEEE Trans. Power Electron., vol. 26, no. 2, pp. 355–363, Feb. 2011. [19] J. Fang, H. Li, and B. Han, “Torque ripple reduction in BLDC torque motor with nonideal back EMF,” IEEE Trans. Power Electron., vol. 27, no. 11, pp. 4630– 4637, Nov. 2012. [20] T.-W. Chun, Q.-V. Tran, H.-H. Lee, and H.-G. Kim, “Sensorless control of BLDC motor drive for an automotive fuel pump using a hysteresis comparator,” IEEE Trans. Power Electron., vol. 29, no. 3, pp. 1382–1391, Mar. 2014. 2016/1/17 Robot and Servo Drive Lab. 32

33. Department of Electrical Engineering Southern Taiwan University Thank you for listening 2016/1/17 Robot and Servo Drive Lab. 33