1. IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 51, NO. 5, SEPTEMBER/OCTOBER 2015 學 生： 張正賢 指導教授： 王明賢

2.  Abstract  Introduction  Conventional Current Limit Strategy  DC-Link Current Sampling Scheme  Simulation And Experiment  Conclusion  References

3.  once the capacitance is reduced, reversal dc- link current will lead to excessive voltage rise in the dc link when conventional current limit strategy is used.  Then, an improved current sampling scheme is presented to replace the cycle-by-cycle mode, which induces failure of current limiting after the elimination of reversal current

4.  Stable dc link is of great importance for the smooth operation of brushless dc motor (BLDCM) drives.  In order to suppress the fluctuation in dc- link voltage, a conventional method is to equip the dc link with sufficient capacitance, which acts as an energy buffer between the three-phase voltage source inverter (VSI) and dc supply.

6. an integrated current limit strategy involves 4 aspects:  current sensing  recognizing over current event  turn off logic  re-enable action after the vanishing of over current

20.  In order to avoid excessive pumping up in dc-link voltage, the traditional all-turn-off current limit logic is replaced by half-turn-off logic,which can eliminate the reversal dc-link current.  half-turn-off logic presented in this paper is effective for the elimination of reversal dc- link current during current limiting.

21. [1] A.M.Hava,U.Ayhan, andV.V.Aban, “A DC bus capacitor design methodfor various inverter applications,” in Proc. ECCE, 2012, pp. 4592–4599. [2] A. Lázaro, A. Barrado, J. Pleite, J. Vázquez, and E. Olías, “Size andcost reduction of the energy-storage capacitors,” in Proc. Appl. Power Electron. Conf. Expo., 2004, vol. 2, pp. 723–729. [3] X.-S. Pu, T. H. Nguyen, D.-C. Lee, K.-B. Lee, and J.-M. Kim, “Fault diagnosis of DC-link capacitors in three-phase AC/DC PWM converters by online estimation of equivalent series resistance,” IEEE Trans. Ind.Electron., vol. 60, no. 9, pp. 4118–4127, Sep. 2013. [4] G. Su and L. Tang, “A segmented traction drive system with a small dcbus capacitor,” Proc. ECCE, 2012, pp. 2847– 2853.

22. [5] D. F. Ortega, W. Shireen, and F. Castelli-Dezza, “Control for grid connected PMSG wind turbine with DC link capacitance reduction,” in Proc.IEEE PES T&D Conf. Expo., 2012, pp. 1–8. [6] Y.-S. Lai, F.-S. Shyu, and Y.-K. Lin, “Novel PWM technique without causing reversal DC-link current for brushless DC motor drives with bootstrap driver,” in Conf. Rec. 14th IEEE IAS Annu. Meeting, 2005,vol. 3, pp. 2182–2188. [7] K.-S. Kan and Y.-Y. Tzou, “Adaptive soft starting method with current limit strategy for sensorless BLDC motors,” in Proc. IEEE ISIE, 2012, pp. 605–610. [8] F. Salha, F. Colas, and X. Guillaud, “Virtual resistance principle for the overcurrent protection of PWM voltage source inverter,” in Proc. ISGT Europe, 2010, pp. 1–6. [9] W.-C. Lee, T.-K. Lee, and D.-S. Hyun, “Comparison of single-sensor current control in the DC link for three-phase voltage-source PWM converters,” IEEE Trans. Ind. Electron., vol. 48, no. 3, pp. 491–505, Jun. 2001. [10] J. W. Dixon and I. A. Leal, “Current control strategy for brushless DC motors based on a common DC signal,” IEEE Trans. Power Electron., vol. 17, no. 2, pp. 232– 240, Mar. 2002. [11] H. Wang, X. Yue, X. Pei, and Y. Kang, “Improved software currentlimiting protection strategy for starting the high-power motor,” in Proc.ICEMS, 2009. pp. 1–4. [12] Y. Wei, Y. Xu, J. Zou, K. Liu, and H. Wang, “Analytic investigation on commutation angle of brushless DC motors with 120◦ voltage source inverter,” Int. J. Appl. Electromagn. Mech., vol. 45, no. 3, pp. 219–225,May 2014.