Sensorless Brushless DC Motor Drive Based on the Zero-Crossing Detection of Back Electromotive Force (EMF) From the Line Voltage Difference  

 

ABSTRACT:

This paper describes a position sensorless operation of permanent magnet brushless direct current (BLDC) motor. The position sensorless BLDC drive proposed, in this paper, is based on detection of back electromotive force (back EMF) zero crossing from the terminal voltages. The proposed method relies on a difference of line voltages measured at the terminals of the motor. It is shown, in the paper, that this difference of line voltages provides an amplified version of an appropriate back EMF at its zero crossings. The commutation signals are obtained without the motor neutral voltage. The effectiveness of the proposed method is demonstrated through simulation and experimental results.

KEYWORDS:

  1. Back electromotive force (EMF) detection
  2. Brushless dc (BLDC) motor
  3. Sensorless control
  4. Zero crossing

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

Fig. 1. Block diagram of the experimental setup.

EXPECTED SIMULATION RESULTS:

 

Fig. 2. Phase current and speed waveform on no-load (experimental).

Fig. 3. Phase current and speed waveform on load (experimental).

Fig. 4. Phase current and speed waveform during loading transient (experimental).

Fig. 5. Phase current, virtual Hall, and real Hall sensor signal for 50% duty

ratio PWM switching

CONCLUSION:

A simple technique to detect back EMF zero crossings for a BLDC motor using the line voltages is proposed. It is shown that the method provides an amplified version of the back EMF. Only three motor terminal voltages need to be measured thus eliminating the need for motor neutral voltage. Running the machine in sensorless mode is then proposed, in this paper, making use of the novel zero-crossing detection algorithm. While starting relies on triggering devices at the zero crossings detected using the proposed algorithm, continuous running is achieved by realizing the correct commutation instants 30delay from the zero crossings. The motor is found to start smoothly and run sensorless even with load and load transients. Simulation and experimental results are shown which validate the suitability of the proposed method.

REFERENCES:

[1] D. O. Koval and C. Carter, “Power quality characteristics of computer loads,” IEEE Trans. on Industry Applications, vol. 33, no. 3, pp. 613- 621, May/June1997.

[2] Abraham I. Pressman, Keith Billings and Taylor Morey, “Switching Power Supply Design,” 3rd ed., McGraw Hill, New York, 2009.

[3] B. Singh, B.N. Singh, A. Chandra, K. Al-Haddad, A. Pandey and D.P. Kothari, “A review of single-phase improved power quality AC-DC converters” IEEE Trans. on Industrial Electronics, vol.50, no.5, pp.962- 981, Oct. 2003.

[4] K. Mino, H. Matsumoto, Y. Nemoto, S. Fujita, D. Kawasaki, Ryuji Yamada, and N. Tawada, “A front-end converter with high reliability and high efficiency,” in IEEE Conf. on Energy Conversion Congress and Exposition (ECCE),2010, pp. 3216-3223.

[5] Jih-Sheng Lai, D. Hurst and T. Key, Switch-mode supply power factor improvement via harmonic elimination methods,” in 6th Annual IEEE Proc. on Applied Power Electronics Conference and Exposition, APEC’91, 1991, pp. 415-422.

Adaptive Speed Control of Brushless DC (BLDC) Motor Based on Interval Type-2 Fuzzy Logic

 

ABSTRACT:

To precisely control the speed of BLDC motors at high speed and with very good performance, an accurate motor model is required. As a result, the controller design can play an important role in the effectiveness of the system. The classic controllers such as PID are widely used in the BLDC motor controllers, but they are not appropriate due to non-linear model of the BLDC motor. To enhance the performance and speed of response, many studies were taken to improve the adjusting methods of PID controller gains by using fuzzy logic. Use of fuzzy logic considering approximately interpretation of the observations and determination of the approximate commands, provides a good platform for designing intelligent robust controller. Nowadays type-2 fuzzy logic is used because of more ability to model and reduce uncertainty effects in rule-based fuzzy systems. In this paper, an interval type-2 fuzzy logic-based proportional-integral-derivative controller (IT2FLPIDC) is proposed for speed control of brushless DC (BLDC) motor. The proposed controller performance is compared with the conventional PID and type-1 fuzzy logic-based PID controllers, respectively in MATLAB/Simulink environment. Simulation results show the superior IT2FLPIDC performance than two other ones.

KEYWORDS:

  1. Brushless DC (BLDC) Motor
  2. Invertal Type-2 Fuzzy Logic
  3. Speed Control
  4. Self-tuning PID Controller

  SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

Figure 1. Block Diagram of speed control of BLDC Motor

EXPECTED SIMULATION RESULTS:

Figure 2. Speed Deviation of BLDC Motor

Figure 3. Load Deviation of BLDC Motor

Figure 4. Torque Deviation of BLDC Motor

 CONCLUSION:

In this paper, the speed control of the BLDC motor is studied and simulated in MATLAB/Simulink. In order to overcome uncertainties and variant working condition, the adjustment of PID gains through fuzzy logic is proposed. In this study, three controller types are considered and compared: conventional PID, type-1 and type-2 fuzzy-based self-tuning PID controllers. The simulation results show that type-2 fuzzy PID controller has superior performance and response than two other ones.

REFERENCES:

[1] A. Sathyan, N. Milivojevic, Y. J. Lee, M. Krishnamurthy, and A. Emadi, “An FPGA-based novel digital PWM control scheme for BLDC motor drives,” IEEE Trans. Ind. Electron., vol. 56, no. 8, pp. 3040–3049,Aug. 2009.

[2] F. Rodriguez and A. Emadi, “A novel digital control technique for brushless DC motor drives,” IEEE Trans. Ind. Electron., vol. 54, no. 5, pp. 2365–2373, Oct. 2007.

[3] Y. Liu, Z. Q. Zhu, and D. HoweDirect Torque Control of Brushless DC Drives With Reduced Torque RippleIEEE Trans. Ind. Appl., vol. 41, no. 2, pp. 599-608, March/April 2005.

[4] T. S. Kim, S. C. Ahn, and D. S. Hyun , “A New Current Control Algorithm for Torque Ripple Reduction of BLDC Motors,” in IECON’01, 27th Conf. IEEE Ind. Electron Society,2001

[5] W. A. Salah, D. Ishak, K. J. Hammadi, “PWM Switching Strategy for Torque Ripple Minimization in BLDC MotorFEI STU, Journal of Electrical Engineering, vol. 62, no. 3, 2011, 141–146.

Sensorless Brushless DC Motor Drive Based on the Zero-Crossing Detection of Back Electromotive Force (EMF) From the Line Voltage Difference

ABSTRACT:

This paper describes a position sensorless operation of permanent magnet brushless direct current (BLDC) motor. The position sensorless BLDC drive proposed, in this paper, is based on detection of back electromotive force (back EMF) zero crossing from the terminal voltages. The proposed method relies on a difference of line voltages measured at the terminals of the motor. It is shown, in the paper, that this difference of line voltages provides an amplified version of an appropriate back EMF at its zero crossings. The commutation signals are obtained without the motor neutral voltage. The effectiveness of the proposed method is demonstrated through simulation and experimental results.

KEYWORDS:

  1. Back electromotive force (EMF) detection
  2. Brushless dc (BLDC) motor
  3. Sensorless control
  4. Zero crossing

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

 

Fig. 1. Block diagram of the experimental setup.

EXPECTED SIMULATION RESULTS:

 

Fig. 2. Phase current and speed waveform on no-load (experimental).

Fig. 3. Phase current and speed waveform on load (experimental).

Fig. 4. Phase current and speed waveform during loading transient (experimental).

Fig. 5. Phase current, virtual Hall, and real Hall sensor signal for 50% duty ratio PWM switching.

CONCLUSION:

A simple technique to detect back EMF zero crossings for a BLDC motor using the line voltages is proposed. It is shown that the method provides an amplified version of the back EMF. Only three motor terminal voltages need to be measured thus eliminating the need for motor neutral voltage. Running the machine in sensorless mode is then proposed, in this paper, making use of the novel zero-crossing detection algorithm. While starting relies on triggering devices at the zero crossings detected using the proposed algorithm, continuous running is achieved by realizing the correct commutation instants 30delay from the zero crossings. The motor is found to start smoothly and run sensorless even with load and load transients. Simulation and experimental results are shown which validate the suitability of the proposed method.

REFERENCES:

[1] K. Iizuka,H.Uzuhashi, M. Kano, T. Endo, and K.Mohri, “Microcomputer control for sensorless brushless motor,” IEEE Trans. Ind. Appl., vol. IA- 21, no. 4, pp. 595–601, May/Jun. 1985.

[2] J. Shao, D. Nolan,M. Teissier, and D. Swanson, “A novel micro controller based sensorless brushless DC (BLDC) motor drive for automotive fuel pumps,” IEEE Trans. Ind. Appl., vol. 39, no. 6, pp. 1734–1740, Nov./Dec. 2003.

[3] T.-H. Kim and M. Ehsani, “Sensorless control of BLDC motors from near-zero to high speeds,” IEEE Trans. Power Electron., vol. 19, no. 6, pp. 1635–1645, Nov. 2004.

[4] S. Ogasawara and H. Akagi, “An approach to position sensorless drive for brushless DC motors,” IEEE Trans. Ind. Appl., vol. 27, no. 5, pp. 928–933, Sep./Oct. 1991.

[5] R. C. Becerra, T. M. Jahns, and M. Ehsani, “Four-quadrant sensorless brushless ECM drive,” in Proc. IEEE APEC, Mar. 1991, pp. 202–209.

A Torque Ripple Suppression Circuit for Brushless DC Motors based on Power DC/DC Converters

 

ABSTRACT:

This paper demonstrates a method of using a DC-DC boost conversion circuit to suppress the commutation torque ripple of a brushless DC (BLDC) motor with rectangular flux distribution. The commutation torque of a BLDC motor is depending on the commutation transient line current. To calculate the line current accurately, the phase resistance is taken into account, and the phase currents rising and falling speed are compared. Furthermore, it is proved that the line current will maintain constant if the DC voltage is lifted in the commutation period. The desired voltage is even higher than the supplied DC link voltage, if the back EMF is higher than two fifths of the input DC voltage. A super-lift Luo-converter is employed to increase the input voltage. The required waveform of the transient voltage is accomplished by changing the parameters of the power DC/DC converter based on the mathematical modeling for the proposed circuit. And the torque ripple is under control. The control stratagem for the torque ripple suppression is described in the paper and its reliability is testified by the simulation and experiment results.

KEYWORDS:

  1. Brushless DC (BLDC) motor
  2. Torque ripple
  3. Super-lift Luo-converter
  4. Mathematical modeling
  5. Commutation current

SOFTWARE: MATLAB/SIMULINK

CIRCUIT DIAGRAM:

Fig. 1. A typical BLDC drive system.

EXPECTED SIMULATION RESULTS:

Fig. 2. Simulated DC link current of the proposed BLDC drive system.

Fig. 3. Measured DC link current of a typical BLDC drive system.

Fig. 4. Measured DC link current of the proposed BLDC drive system.

REFERENCES:

[1] R Carlson, M Lajoie-Mazenc, J Fagundes. Analysis of torque ripple due to phase commutation in Brushless DC machines[J]. IEEE Trans. Ind.Applicat., 1992, 28: 632-638.

[2] Y Murai, Y Kawase, K Ohashi, et al. Torque ripple improvements for brushless DC miniature motors[J]. IEEE Transactions on Industry Applications, 1989, 25(3): 441-450.

[3] Liu Yong, Zhu Z Q and David H, “Commutation-Torque-Ripple Minimization in Direct-Torque-Controlled PM Brushless DC Drives,” IEEE Trans on Industry Applications, vol.43, pp.1012-1021, July 2007.

[4] Zhang Xiaofeng and Lu Zhengyu, “A New BLDC Motor Drives Method Based on BUCK Converter for Torque Ripple Reduction,” IEEE 5th International Conf. on Power Electronics and Motion Control, vol. 2, pp. 1-4, August 2006.

[5] Ki-Yong Nam, Woo-Taik Lee, Choon-Man Lee and Jung-Pyo Hong, “Reducing torque ripple of brushless DC motor by varying input voltage,” IEEE Trans. on Magnetics, vol.42, pp. 1307 – 1310, April 2006.