Hybrid converter topology for reducing torque ripple of BLDC motor

ABSTRACT

This study investigates the torque ripple performance of brushless DC (BLDC) motor drive system by integrating bothmodified single-ended primary inductor converter (SEPIC) and silicon carbide metal–oxide–semiconductor field-effect transistorbased three-level neutral-point-clamped (NPC) inverter. In BLDC motor, the high commutation torque ripple is an importantorigin of vibration, speed ripple and prevents the use of the BLDC motor drive system in high-performance and high-precisionapplications. For torque ripple reduction, the modified SEPIC converter is employed at the entrance of the three-level NPCinverter, which regulates the DC-link voltage according to the motor speed. Moreover, the three-level NPC inverter is employedas a second-stage converter to suppress current ripple for further torque ripple reduction. Finally, the performance of theproposed hybrid converter topology is verified by simulation and laboratory experimental results.

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

(a) Proposed converter topology

EXPECTED SIMULATION RESULTS

Fig. 2Phase current and torque waveforms

(a) Phase current and torque waveforms from simulation at 2500 rpm and 0.825 N m, (b) Phase current and torque waveforms from simulation at 2500 rpm and 0.825 N m, (c) Phase

current and torque waveforms from simulation at 6000 rpm and 0.825 N m, (d) Phase current and torque waveforms from simulation at 6000 rpm and 0.825 N m

CONCLUSION

A novel hybrid circuit topology has been proposed in this paperwhich is built by a modified SEPIC converter and a SiC-MOSFETbasedthree-level NPC converter for minimising torque ripple in aBLDC motor drive system. For efficient reduction of torque ripple,the first stage is the modified SEPIC converter that lifts the DClinkvoltage to the desired value based on the motor speedmeasurement. For further torque ripple reduction, the three-levelNPC inverter is employed as the second-stage converter tosuppress current ripple. Experimental results show that theproposed hybrid converter topology can suppress the torque rippleto 14.6% at the speed of 6000 rpm, commutation torque ripple isreduced substantially and produce smooth torque waveform thanthe BLDC motor driven by the two-level, three-level NPC, twolevelinverter with DC-link voltage control, and two-level inverterwith SEPIC converter and switch selection circuit topologies.

REFERENCES

[1] Singh, B., Bist, V.: ‘An improved power quality bridgeless Cuk converter fedBLDC motor drive for air conditioning system’, IET Power Electron., 2013,6, (5), pp. 902–913

[2] Carlson, R., Lajoie-Mazenc, M., Fagundes, J.C.D.S.: ‘Analysis of torqueripple due to phase commutation in brushless dc machines’, IEEE Trans. Ind.Appl., 1992, 28, (3), pp. 632–638

[3] Lee, S.K., Kang, G.H., Hur, J., et al.: ‘Stator and rotor shape designs ofinterior permanent magnet type brushless DC motor for reducing torquefluctuation’, IEEE Trans. Magn., 2012, 48, pp. 4662–4665

[4] Seo, U.J., Chun, Y.D., Choi, J.H., et al.: ‘A technique of torque ripplereduction in interior permanent magnet synchronous motor’, IEEE Trans.Magn., 2011, 47, (10), pp. 3240–3243

[5] Murai, Y., Kawase, K., Ohashi, K., et al.: ‘Torque ripple improvement forbrushless DC miniature motors’, IEEE Trans. Ind. Appl., 1989, 25, (3), pp.441–450

High-performance multilevel inverter drive of brushless DC Motor

ABSTRACT:

The brushless DC (BLDC) motor has numerous applications in high-power systems; it is simple in construction, is cheap, requires less maintenance, has higher efficiency, and has high power in the output unit. The BLDC motor is driven by an inverter. This paper presents design and simulation for a three-phase three-level inverter to drive the BLDC motor. The multilevel inverter is driven by discrete three-phase pulse width modulation (DPWM) generator that forced-commuted the IGBT’s three-level converters using three bridges to vectored outputs 12- pulses with three levels. Using DPWM with a three-level inverter solves the problem of harmonic distortions and low electromagnetic interference. This topology can attract attention in high-power and high-performance voltage applications. It provides a three-phase voltage source with amplitude, phase, and frequency that are controllable. The proposed model is used with the PID controller to follow the reference speed signal designed by variable steps. The system design is simulated by using Matlab/Simulink. Satisfactory results and high performance of the control with steady state and transient response are obtained. The results of the proposed model are compared with the variable DC-link control. The results of the proposed model are more stable and reliable.

KEYWORDS:

1.      Brushless DC Motor

2.      Multilevel Inverter

3.      High-Performance Drive

4.      Pulse Width Modulation (PWM)

5.      Maltlab

6.      Simulink

SOFTWARE: MATLAB/SIMULINK

CIRCUIT DIAGRAM:

Figure 1. BLDC motor with MLI driven with PID controller.

EXPECTED SIMULATION RESULTS:

Figure. 2. Output of three-phase three-level inverter with DPWM.

Figure 3. The sample from output of the DPWM

Figure 4. Analysis of response for the proposed MLI with PID controller of BLDC motor.

Fig. 5. Two outputs of controllers with proposed MLI and variable DC-link

CONCLUSION:

The proposed MLI performance analysis was successfully presented by using Matlab/Simulink software. The proposed topology can be easily extended to a higher-level inverter. The simulation results were sine waves and exhibited fewer ripples and low losses. This system would show its feasibility in practice. The vector control was described in adequate detail and was implemented with a three-level MLI. This method enabled the operation of the drive at zero direct axis stator current. Transient results were obtained when a DPWM was started from a standstill to a required speed. The performance of the vector control in achieving a fast reversal of PDPWM even at very high speed ranges is quite satisfactory. The performance of the proposed three-phase MLI was investigated and was found to be quite satisfactory. A comparison was made between the PID controller–based proposed model MLI and the controller with variable DC-link voltage. The results showed that the proposed model responded better in transient and steady states and was more reliability with high performance.

REFERENCES:

 [1] P. D. Kiran, M. Ramachandra, “Two-Level and Five-Level Inverter Fed BLDC Motor Drives”, International Journal of Electrical and Electronics Engineering Research, Vol. 3, Issue 3, pp 71-82, Aug 2013

[2] N. Karthika, A. Sangari, R. Umamaheswari , “Performance Analysis of Multi Level Inverter with DC Link Switches for Renewable Energy Resources”, International Journal of Innovative Technology and Exploring Engineering, Volume-2, Issue-6, pp 171-176, May 2013

[3] A. Jalilvand R. Noroozian M. Darabian, “Modeling and Control Of Multi-Level Inverter for Three-Phase Grid-Connected Photovoltaic Sources”, International Journal on Technical and Physical Problems of Engineering, Iss. 15, Vol. 5, No.2, pp 35-43, June 2013

[4] P. Karuppanan, K. Mahapatra, “PI, PID and Fuzzy Logic Controlled Cascaded Voltage Source Inverter Based Active Filter For Power Line Conditioners”, Wseas Transactions On Power Systems, Issue 4, Volume 6, pp 100-109, October 2011

[5] D. Balakrishnan, D. Shanmugam, K.Indiradevi, “Modified Multilevel Inverter Topology for Grid Connected PV Systems”, American Journal of Engineering Research, Vol. 02, Iss.10, pp-378-384, 2013

Compensation of torque ripple in high performance BLDC motor drives

ABSTRACT:

Brushless DC motor drives (BLDC) are finding expanded use in high performance applications where torque smoothness is essential. The nature of the square-wave current excitation waveforms in BLDC motor drives permits some important system simplifications compared to sinusoidal permanent magnet AC (PMAC) machines. However, it is the simplicity of the BLDC motor drive that is responsible for causing an additional source of ripple torque commonly known as commutation torque to develop. In this paper, a compensation technique for reducing the commutation torque ripple is proposed. With the experimental results, the proposed method demonstrates the effectiveness for a control system using the BLDC motors that requires high speed and accuracy.

KEYWORDS:

1.      Brushless DC motor drives

2.      Commutation

3.      Torque ripple

4.      Trapezoidal back EMF

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

Fig. 1. The block diagram of the speed controller.

EXPECTED SIMULATION RESULTS:

Fig. 2. Experimental result in low-speed range (without compensation).

Fig. 3. Experimental result in low-speed range (with compensation).

Fig. 4. Experimental result in the high-speed range (without compensation).

Fig. 5. Experimental result in the high-speed range (with compensation).

Fig. 6. Experimental result in the high-speed range (with compensation).

Fig. 7. Sine wave response for the proposed speed controller.

CONCLUSION:

This paper has proposed a compensation technique for reducing the commutation torque ripple in high-performance BLDC motor drives. The idea is to equalize the mismatched times of two commutated phase currents during the commutation intervals. In low-speed operation, a method to slow down the rising time of the on-going phase current can be a desirable technique. In high-speed operation, a method to slow down the falling time of the off-going phase current becomes a desirable strategy. However, it is not easy to implement the proposed strategies by using cost-effective one-chip microprocessors because it is needed to calculate the commutation time intervals within the sampling period in low and high speed operation. Instead of calculating the commutation time intervals, two dimensional lookup tables that describe the relation of the commutation time interval and the motor parameters such as the back EMF and the initial motor current, are used. For the experiments, a 16-bit microprocessor was used for the controller. Additionally a CPLD (1600 gates) was used to generate gate signals of the inverter and the commutation time signals. To verify the feasibility of the propose method, it is applied to the spindle motor drive control for the industrial sewing machines. The effects of torque ripple are particularly undesirable in the industrial sewing machines. They lead to speed oscillations which cause deterioration in the performance. In addition, the torque ripple may excite resonances in the mechanical portion of the drive system, produce acoustic noise. With the experimental results, the proposed method demonstrates the effectiveness for a high-performance control system using the BLDC motors that requires high speed and accuracy.

REFERENCES:

Berendesen, C., Champenois, G., & Bolopion, A. (1993). Commutation strategies for brushless DC motor: influence on instant torque. IEEE Transactions on Power Electronics, 8(2), 231–236. Carlson, R., Lajoie-Mazenc, M., & Fagundes, J. C. S. (1992). Analysis of torque ripple due to phase commutation in brushless DC machines. IEEE Transactions on Industry Applications, 28(3), 632–638.

Chung, K., Zhu, Y., Lee, I., Lee, K., & Cho, Y. (2007). Simulation of the reduction of force ripples of the permanent magnet linear synchronous motor. Journal of E. E. T, 2(2), 208–215. Holtz, J., & Springob, L. (1996). Identification and compensation of torque ripple in high-precision permanent magnet motor drives. IEEE Transactions on Industrial Electronics, 43(2), 309–320.

Jahns, T. M., & Soong, W. L. (1996). Pulsating torque minimization techniques for permanent magnet AC motor drives—a review. IEEE Transactions on Industrial Electronics, 43(2), 321–330.

Commutation Torque Ripple Reduction in Brushless DC Motor Drives Using a Single DC Current Sensor

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 brushless dc motors,” in Proc. Int. Conf. Power Electron., 1998, pp. 380–385.

[4] J. Cros, J. M. Vinassa, S. Clenet, S. Astier, and M. Lajoie-Mazenc, “A novel current control strategy in trapezoidal EMF actuators to minimize torque ripples due to phases commutations,” in Proc. Eur. Power Electron. Conf., 1993, pp. 266–271.

[5] Y. Murai,Y. Kawase, K. Ohashi, K. Nagatake, and K. Okuyama, “Torque ripple improvement for brushless DC miniature motors,” IEEE Trans. Ind. Applicat., vol. 25, pp. 441–450, May/June 1989.

Approach for torque ripple reduction for brushless DC motor based on three-level neutral-point-clamped inverter with DC–DC converter

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, G.H., Cho, H.O., Hong, J.P.: ‘Characteristic analysis of brushless motor considering drive type’, Trans. Korean Inst. Electr. Eng., 2002, 5, pp. 589–591

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 novel space-vector current control method for commutation torque ripple 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., Chanwon, P., Chansu, Yu.: ‘Compensation of torque ripple in high performance BLDC motor drives’, Control Eng. Pract., 2010, 18, pp. 1166–1172

An Adjustable-Speed PFC Bridgeless Buck–Boost Converter-Fed BLDC Motor Drive

ABSTRACT:

This paper presents a power factor corrected (PFC) bridgeless (BL) buck–boost converter-fed brushless direct current (BLDC) motor drive as a cost-effective solution for low-power applications. An approach of speed control of the BLDC motor by controlling the dc link voltage of the voltage source inverter (VSI) is used with a single voltage sensor. This facilitates the operation of VSI at fundamental frequency switching by using the electronic commutation of the BLDC motor which offers reduced switching losses. A BL configuration of the buck–boost converter is proposed which offers the elimination of the diode bridge rectifier, thus reducing the conduction losses associated with it. A PFC BL buck–boost converter is designed to operate in discontinuous inductor current mode (DICM) to provide an inherent PFC at ac mains. The performance of the proposed drive is evaluated over a wide range of speed control and varying supply voltages (universal ac mains at 90–265 V) with improved power quality at ac mains. The obtained power quality indices are within the acceptable limits of international power quality standards such as the IEC 61000-3-2. The performance of the proposed drive is simulated in MATLAB/Simulink environment, and the obtained results are validated experimentally on a developed prototype of the drive.

KEYWORDS:

1.      Bridgeless (BL) buck–boost converter

2.      Brushless direct current (BLDC) motor

3.       Discontinuous inductor current mode (DICM)

4.       Power factor corrected (PFC)

5.      Power quality

SOFTWARE: MATLAB/SIMULINK

CIRCUIT DIAGRAM:

Fig. 1. Proposed BLDC motor drive with front-end BL buck–boost converter.

EXPECTED SIMULATION RESULTS:

Fig. 2. Steady-state performance of the proposed BLDC motor drive at rated conditions.

Fig. 3. Harmonic spectra of supply current at rated supply voltage and rated

loading on BLDC motor for a dc link voltage of (a) 200 V and (b) 50 V.

Fig. 4. Dynamic performance of proposed BLDC motor drive during (a) starting, (b) speed control, and (c) supply voltage variation at rated conditions.

Fig. 5. Harmonic spectra of supply current at rated loading on BLDC motor

with dc link voltage as 200 V and supply voltage as (a) 90 V and (b) 270 V.

Fig. 6. Steady-state performance of the proposed BLDC motor drive at rated

conditions with dc link voltage as (a) 200 V and (b) 50 V.

CONCLUSION:

A PFC BL buck–boost converter-based VSI-fed BLDC motor drive has been proposed targeting low-power applications. A new method of speed control has been utilized by controlling the voltage at dc bus and operating the VSI at fundamental frequency for the electronic commutation of the BLDC motor for reducing the switching losses in VSI. The front-end BL buck–boost converter has been operated in DICM for achieving an inherent power factor correction at ac mains. A satisfactory performance has been achieved for speed control and supply voltage variation with power quality indices within the acceptable limits of IEC 61000-3-2. Moreover, voltage and current stresses on the PFC switch have been evaluated for determining the practical application of the proposed scheme. Finally, an experimental prototype of the proposed drive has been developed to validate the performance of the proposed BLDC motor drive under speed control with improved power quality at ac mains. The proposed scheme has shown satisfactory performance, and it is a recommended solution applicable to low-power BLDC motor drives.

REFERENCES:

[1] C. L. Xia, Permanent Magnet Brushless DC Motor Drives and Controls. Hoboken, NJ, USA: Wiley, 2012.

[2] J. Moreno, M. E. Ortuzar, and J. W. Dixon, “Energy-management system for a hybrid electric vehicle, using ultracapacitors and neural networks,” IEEE Trans. Ind. Electron., vol. 53, no. 2, pp. 614–623, Apr. 2006.

[3] Y. Chen, C. Chiu, Y. Jhang, Z. Tang, and R. Liang, “A driver for the singlephase brushless dc fan motor with hybrid winding structure,” IEEE Trans. Ind. Electron., vol. 60, no. 10, pp. 4369–4375, Oct. 2013.

[4] 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.

[5] H. A. Toliyat and S. Campbell, DSP-Based Electromechanical Motion Control. Boca Raton, FL, USA: CRC Press, 2004.