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

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

 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

 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.

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

 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.

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