ABSTRACT:
This study proposes a novel topology for
reducing commutation torque ripple in a brushless DC motor (BLDCM) drive system
using a three-level neutral-point-clamped (NPC) inverter combined with
single-ended primary-inductor converter (SEPIC) converters. In the BLDCM,
current ripples arise because of the influence of stator winding inductance,
which generates torque ripples. The torque ripple that is generated in the
commutation period prevents the use of BLDCM in high-precision servo drive systems.
In this study, two-stage converters are proposed to reduce the torque ripple.
The first stage consists of two SEPIC converters to obtain the desired
commutation voltage according to motor speed. A dc-link voltage selection
circuit is combined with the SEPIC converters to apply the optimised voltage
during the commutation interval. To reduce the torque ripple further, a
three-level NPC inverter is used to apply a half dc-link voltage across the motor
winding and this effectively reduces the torque ripple. Experimental results
show that the proposed topology is able to reduce commutation torque ripple significantly
under both low-speed and high-speed operation.
SOFTWARE:
MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig.
1 Simulation block diagram of the proposed topology with the BLDCM
EXPECTED SIMULATION RESULTS:
Fig.
2 Simulation results of phase current and torque a
Phase current waveform of the conventional control at 3000 rpm and 0.825 Nm b
Torque waveform of the conventional control at 3000 rpm and 0.825 Nm c
Phase current waveform of the proposed topology at 3000 rpm and 0.825 Nm d
Torque waveform of the proposed topology at 3000 rpm and 0.825 Nm
Fig.
3 Simulation results of phase current and torque a
Phase current waveform of the conventional control at 6000 rpm and 0.825 Nm b
Torque waveform of the conventional control at 6000 rpm and 0.825 Nm c
Phase current waveform of the proposed topology at 6000 rpm and 0.825 Nm d
Torque waveform of the proposed topology at 6000 rpm and 0.825 Nm
CONCLUSION:
In this paper, a novel topology has been
proposed to suppress the commutation torque ripple of a BLDCM using two SEPIC converters
and a MOSFET-based three-level NPC inverter. The SEPIC converters are used to
adjust the dc-link voltage and thus to suppress the torque ripple during the commutation
period. To verify the feasibility of the proposed topology, simulation and
experiments were conducted using low and high speeds. The results of this paper
have demonstrated that the proposed topology can effectively reduce the commutation
torque ripple. Therefore, the proposed solution has high potential for
vehicular and aerospace applications in which torque ripple minimization is of
great importance.
REFERENCES:
1 Lee, J.G., Park, C.S., Lee, J.J., Lee,
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2 Kim, T.H., Ehsani, M.: ‘Sensorless
control of the BLDC motor from near-zero to high speeds’, IEEE Power Electron.,
2004, 19, (6), pp. 1635–1645
3 Viswanathan, V., Jeevananthan, S.: ‘A
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reduction of brushless DC motor drive’, Arab Sci. J. Eng., 2013, 38, (10), pp.
1773–2784
4 Miller, T.J.E.: ‘Brushless PM and
reluctance motor drives’ (Clarendon press, New York, 1989)
5 Ilhwan, K., Nobuaki, N., Sungsoo, K.,
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