ABSTRACT:
This paper
presents a comprehensive study on reducing commutation torque ripples generated
in brushless dc motor drives with only a single dc-link current sensor
provided. In such drives, commutation torque ripple suppression techniques that
are practically effective in low speed as well as high speed regions are
scarcely found. The commutation compensation technique proposed here is based
on a strategy that the current slopes of the incoming and the outgoing phases
during the commutation interval can be equalized by a proper duty-ratio
control. Being directly linked with deadbeat current control scheme, the proposed
control method accomplishes suppression of the spikes and dips superimposed on
the current and torque responses during the commutation intervals of the
inverter. Effectiveness of the proposed control method is verified through
simulations and experiments.
KEYWORDS:
1. Brushless dc motor drives
2. Commutation torque ripple reduction
3. Single dc current sensor
SOFTWARE:
MATLAB/SIMULINK
CIRCUIT DIAGRAM:
Fig.
1. Basic configuration of trapezoidal brushless dc motor drives with dc link
current controlled.
EXPECTED SIMULATION RESULTS:
(a)
(b)
(c)
Fig.
2. Simulation results in the low speed range: (a) phase currents, (b)
dc-link
current, and (c) commutation torque ripple.
(a)
(b)
(c)
Fig.
3. Simulation results in the high speed range: (a) phase currents, (b)
dc-link
current, and (c) commutation torque ripple.
CONCLUSION:
In this paper, a commutation torque
ripple reduction method has been proposed for brushless dc motor drives using a
single dc current sensor. In such drives, the dc-link current sensor cannot
give any information corresponding to the motor currents during the phase current
commutation intervals. Using the commutated phase current waveforms synthesized
from the measured dc current, a duty ratio control strategy has been devised to
equalize the two mismatched commutation time intervals. By being directly linked
with the deadbeat current control scheme, the proposed control method
accomplishes successful suppression of the spikes and dips superimposed on the
current and torque responses during the commutation intervals. This scheme
shows attractive effectiveness in the low and the high speed regions through
simulations and experiments.
REFERENCES:
[1] T. M. Jahns andW. L. Soong,
“Pulsating torque minimization techniques for permanent magnet AC motor
drives—a review,” IEEE Trans. Ind. Electron., vol. 43, pp. 321–330, Apr.
1996.
[2] R. Carlson, M. Lajoie-Mazenc, and J.
C. S. Fagundes, “Analysis of torque ripple due to phase commutation in
brushless DC machines,” IEEE Trans. Ind. Applicat., vol. 28, pp.
632–638, May/June 1992.
[3] K.-W. Lee, J.-B. Park, H.-G. Yeo, J.-Y.
Yoo, and H.-M. Jo, “Current control algorithm to reduce torque ripple in
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380–385.
[4] J. Cros, J. M. Vinassa, S. Clenet,
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[5] Y. Murai,Y. Kawase, K. Ohashi, K. Nagatake,
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