Commutation Torque Ripple Reduction in BLDC Motor Using Modified SEPIC Converter and Three-level NPC Inverter

ABSTRACT:

This paper presents a new power converter topology to suppress the torque ripple due to the phase current commutation of a brushless DC motor (BLDCM) drive system. A combination of a 3-level diode clamped multilevel inverter (3-level DCMLI), a modified single-ended primary-inductor converter (SEPIC), and a dc-bus voltage selector circuit are employed in the proposed torque ripple suppression circuit. For efficient suppression of torque pulsation, the dc-bus voltage selector circuit is used to apply the regulated dc-bus voltage from the modified SEPIC converter during the commutation interval. In order to further mitigate the torque ripple pulsation, the 3-level DCMLI is used in the proposed circuit. Finally, simulation and experimental results show that the proposed topology is an attractive option to reduce the commutation torque ripple significantly at low and high speed applications.

KEYWORDS:

  1. Brushless direct current motor (BLDCM)
  2. Dc-bus voltage control
  3. Modified single-ended primary-inductor converter
  4. 3-level diode clamped multilevel inverter (3-level DCMLI)
  5. Torque ripple

 SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

Fig. 1. Proposed converter topology with a dc-bus voltage selector circuit for BLDCM

 EXPECTED SIMULATION RESULTS:

 

 Fig. 2. Simulated waveforms of phase current and torque at 1000 rpm and 0.825 Nm with 5 kHz switching frequency. (a) BLDCM fed by 2-level inverter. (b) BLDCM fed by 3-level DCMLI. (c) BLDCM fed by 2-level inverter with SEPIC converter and a switch selection circuit. (d) BLDCM fed by proposed topology.

Fig. 3. Simulated waveforms of phase current and torque at 6000 rpm and 0.825 Nm with 5 kHz switching frequency. (a) BLDCM fed by 2-level inverter. (b) BLDCM fed by 3-level DCMLI. (c) BLDCM fed by 2-level inverter with SEPIC converter and a switch selection circuit. (d) BLDCM fed by proposed topology.

Fig. 4. Simulated waveforms of phase current and torque at 1000 rpm and 0.825 Nm with 20 kHz switching frequency. (a) BLDCM fed by 2-level inverter. (b) BLDCM fed by 3-level DCMLI. (c) BLDCM fed by 2-level inverter with SEPIC converter and switch a selection circuit. (d) BLDCM fed by proposed topology.

Fig. 5. Simulated waveforms of phase current and torque at 6000 rpm and 0.825 Nm with 20 kHz switching frequency. (a) BLDCM fed by 2-level inverter. (b) BLDCM fed by 3-level DCMLI. (c) BLDCM fed by 2-level inverter with SEPIC converter and a switch selection circuit. (d) BLDCM fed by proposed topology.

Fig. 6. Simulated waveforms of phase current and torque at 1000 rpm and 0.825 Nm with 80 kHz switching frequency. (a) BLDCM fed by 2-level inverter. (b) BLDCM fed by 3-level DCMLI. (c) BLDCM fed by 2-level inverter with SEPIC converter and a switch selection circuit. (d) BLDCM fed by proposed topology.

Fig. 7. Simulated waveforms of phase current and torque at 6000 rpm and 0.825 Nm with 80 kHz switching frequency. (a) BLDCM fed by 2-level inverter. (b) BLDCM fed by 3-level DCMLI. (c) BLDCM fed by 2-level inverter with SEPIC converter and a switch selection circuit. (d) BLDCM fed by proposed topology.

CONCLUSION:

In this paper, a commutation torque ripple reduction circuit has been proposed using 3-level DCMLI with modified SEPIC converter and a dc-bus voltage selector circuit. A laboratory-built drive system has been tested to verify the proposed converter topology. The suggested dc-bus voltage control strategy is more effective in torque ripple reduction in the commutation interval. The proposed topology accomplishes the successful reduction of torque ripple in the commutation period and experimental results are presented to compare the performance of the proposed control technique with the conventional 2-level inverter, 3-level DCMLI, 2-level inverter with SEPIC converter and the switch selection circuit-fed BLDCM. In order to obtain significant torque ripple suppression, quietness and higher efficiency, 3-level DCMLI with modified SEPIC converter and the voltage selector circuit is a most suitable choice to obtain high-performance operation of BLDCM. The proposed topology may be used for the torque ripple suppression of BLDCM with the very low stator winding inductance.

REFERENCES:

[1] N. Milivojevic, M. Krishnamurthy, Y. Gurkaynak, A. Sathyan, Y.-J. Lee, and A. Emadi, “Stability analysis of FPGA-based control of brushless DC motors and generators using digital PWM technique,” IEEE Trans. Ind. Electron., vol. 59, no. 1, pp. 343–351, Jan. 2012.

[2] X. Huang, A. Goodman, C. Gerada, Y. Fang, and Q. Lu, “A single sided matrix converter drive for a brushless dc motor in aerospace applications,” IEEE Trans. Ind. Electron., vol. 59, no. 9, pp. 3542–3552, Sep. 2012.

[3] X. Huang, A. Goodman, C. Gerada, Y. Fang, and Q. Lu, “Design of a five-phase brushless DC motor for a safety critical aerospace application,” IEEE Trans. Ind. Electron., vol. 59, no. 9, pp. 3532-3541, Sep. 2012.

[4] J.-G. Lee, C.-S. ark, J.-J. Lee, G. H. Lee, H.-I. Cho, and J.-P. Hong, “Characteristic analysis of brushless motor condering drive type,” KIEE, pp. 589-591, Jul. 2002.

Brushless DC motor drive with power factor regulation using Landsman converter

IET Power Electronics, 2016

 ABSTRACT: This study presents a novel configuration of power factor regulation (PFR)-based Landsman converter feeding a brushless DC motor (BLDCM) drive for low-power (400 W) white goods applications. The speed control of the drive is achieved through adjusting the DC bus voltage of voltage source inverter (VSI) feeding to a BLDCM. Moreover, low frequency switching signals are used for electronic commutation of BLDCM, which reduces the switching power losses of six solid-state switches of VSI. This Landsman converter-based front-end power factor corrector operating in discontinuous inductor current mode is used to control DC bus voltage and PFR is achieved inherently. The DC bus voltage of the drive is controlled by using a single DC voltage sensor. For evaluating the performance of proposed drive, a prototype is developed in the laboratory. The performance of the BLDCM is also analysed for its operation at varying AC mains voltage (90–265 V). Experiential results for power quality indices are found within the limits of power quality standard IEC 61000-3-2.

 SOFTWARE: MATLAB/SIMULINK

CIRCUIT DIAGRAM:

Fig. 1Circuit configurations of a PFR based

Proposed drive scheme of a Landsman converter fed PMBLDCM drive

EXPECTED SIMULATION RESULTS:

 

Fig. 2 Performance of proposed drive at rated torque on motor

a Steady-state performance of the proposed BLDCM drive at rated load on BLDCM with DC-link voltage as 200 V and supply voltage as 220 V

b–d Obtained power quality indices

Fig. 3 Performance of proposed drive at rated load on motor

a Steady-state performance of the proposed BLDCM drive at rated load on BLDCM with DC-link voltage as 60 V and supply voltage as 220 V

b–d Obtained power quality indices

Fig. 4 Performance of PFR-based Landsman converter

a Input and output inductor’s currents and intermediate capacitor’s waveforms

b Current and voltage stress on a PFR switch at rated load on BLDCM at rated condition

Fig. 5 Dynamic performances of the proposed BLDCM drive system during

a Starting at 60 V

b Speed control for variation in DC bus voltage from 100 to 150 V

c Load variation

d Supply voltage change from 260 to 210 V

CONCLUSION:

A PFR-based Landsman converter fed BLDCM drive has been proposed for the use in low power household appliances. Adjustable voltage control of DC bus of VSI has been used to control the speed of BLDCM which eventually has given the freedom to operate the VSI in low frequency switching operation for minimum switching losses. A front-end Landsman converter-based PFR operating in DICM has been applied for double objectives of DC bus voltage control and achieving a UPF at AC supply. Resulted performance for presented drive has been found quite satisfactory for its operation at variation of speed over a wide range. A prototype of Landsman-based BLDCM drive has been implemented with acceptable test results for its operation over complete speed range and its operation over universal AC mains. The stress of the PFR converter switch has been evaluated to conclude its feasibility. The obtained power quality parameters are found within the limit of various international standards like as IEC 61000-3-2.

REFERENCES:

1 Gieras, J.F., Wing, M.: ‘Permanent magnet motor technology-design and application’ (Marcel Dekker Inc., New York, 2011)

2 Xia, C.L.: ‘Permanent magnet brushless DC motor drives and controls’ (Wiley Press, Beijing, 2012)

3 Zhu, Z.Q., Howe, D.: ‘Electrical machines and drives for electric, hybrid, and fuel cell vehicles’, IEEE Proc., 2007, 95, (4), pp. 746–765

4 Sozer, Y., Torrey, D.A., Mese, E.: ‘Adaptive predictive current control technique for permanent magnet synchronous motors’, IET Power Electron., 2013, 6, pp. 9–19

5 Hung, C.W., Lin, C.T., Liu, C.W., et al.: ‘A variable-sampling controller for brushless DC motor drives with low-resolution position sensors’, IEEE Trans.Ind. Electron., 2007, 54, (5), pp. 2846–2852