Transcript Department of Electrical Engineering Southern Taiwan University

Robot and Servo Drive Lab.
Assessing pulse-width modulation
techniques for brushless dc motor
drives
BY YEN-SHIN LAI & YONG-KAI LIN
IEEE INDUSTRY APPLICATIONS MAGAZINE ∙SEPT j OCT 2008 ∙
WWW. IEEE.ORG/IAS pp34-44.
Student: Tai-Rong Lai
Professor: Ming-Shyan Wang
Department of Electrical Engineering
Southern Taiwan University
2016/4/11
Outline

Abstract

PWM techniques for BLDCM Drive

Driver Circuit

Reversal dc-Link Current

Circulating Current of Floating Phase

Back EMF Detection

Assessment of PWM Techniques—Theoretical Analysis and Experimental Confirmation

Conclusions

References
2016/4/11
2
Department of Electrical Engineering
Southern Taiwan University
Robot and Servo Drive Lab.
Abstract

The aim of this article is to assess the PWM techniques for
BLDCM drives.
• Driver circuit
• Reversal dc-link current
• Circulating current of floating phase
• Back-EMF
3
Department of Electrical Engineering
Southern Taiwan University
PWM techniques for BLDCM Drive
4
Department of Electrical Engineering
Southern Taiwan University
PWM techniques for BLDCM Drive
5
Department of Electrical Engineering
Southern Taiwan University
PWM techniques for BLDCM Drive
6
Department of Electrical Engineering
Southern Taiwan University
Driver Circuit

Photocoupler driver

Isolated transformer driver

Bootstrap driver
7
Department of Electrical Engineering
Southern Taiwan University
Photocoupler driver
8
Department of Electrical Engineering
Southern Taiwan University
Isolated transformer driver
9
Department of Electrical Engineering
Southern Taiwan University
Bootstrap driver
10
Department of Electrical Engineering
Southern Taiwan University
Driver Circuit
11
Department of Electrical Engineering
Southern Taiwan University
Reversal dc-Link Current
CH1:chopper
CH2:Vu CH3:Iu CH4:Idc
12
Department of Electrical Engineering
Southern Taiwan University
Reversal dc-link current, phase U
13
Department of Electrical Engineering
Southern Taiwan University
Circulating Current of Floating Phase
14
Department of Electrical Engineering
Southern Taiwan University
Circulating Current of Floating Phase
15
Department of Electrical Engineering
Southern Taiwan University
Back EMF Detection



Vp:denotes the terminal voltage for the phase connected to the
positive dc-link rail during PWM control period.
Vn indicates the terminal voltage for the phase connected to
the negative dc-link rail.
Vo is the terminal voltage for the floating phase.
16
Department of Electrical Engineering
Southern Taiwan University
Back EMF Detection
17
Department of Electrical Engineering
Southern Taiwan University
Assessment of PWM Techniques—Theoretical
Analysis and Experimental Confirmation
Block diagram of the sensorless experimental system
18
Department of Electrical Engineering
Southern Taiwan University
Motor specifications




Number of poles=8
Rated power=70W
V dc= 24 V
Rated speed=2,500 rpm
19
Department of Electrical Engineering
Southern Taiwan University
CH1: high-side control,
CH2: low-side control,
CH3: terminal voltage
CH4: phase current,
duty = 20%.
20
Department of Electrical Engineering
Southern Taiwan University
CH1: high-side control,
CH2: low-side control,
CH3: terminal voltage
CH4: phase current,
duty = 80%.
21
Department of Electrical Engineering
Southern Taiwan University
CH1: high-side control,
CH2: low-side control,
CH3: terminal voltage
CH4: dc-link current,
duty = 20%.
22
Department of Electrical Engineering
Southern Taiwan University
CH1: high-side control,
CH2: low-side control,
CH3: terminal voltage
CH4: dc-link current,
duty = 80%.
23
Department of Electrical Engineering
Southern Taiwan University
CH1: terminal voltage
CH2: phase current,
duty = 80%.
No load
24
Department of Electrical Engineering
Southern Taiwan University
25
Department of Electrical Engineering
Southern Taiwan University
Conclusions

The aim of this article is to assess the special features of five
PWM techniques for BLDCM control. As shown here, the
indexes include reversal dc-link current, circulating current,
driver circuit, and back-EMF detection. Theoretical analysis is
presented and followed by the experimental results. An
inverter-controlled BLDCM drive without using any hall
sensor and current sensor is set up. Experimental results fully
support the analysis. These results provide the whole picture
for applications reference.
26
Department of Electrical Engineering
Southern Taiwan University
References






[1] Seiko Epson Corp., ‘‘Brushless dc motor without position sensor and its
controller,’’ E.P. Patent 0 553 354 B1, 1993.
[2] Tokyo Shibaura Electric Co., ‘‘Inverter and air conditioner controlled
by the same,’’ U.S. Patent 5 486 743, 1996.
[3] ST Microelectronics, ‘‘Control of a brushless motor,’’ U.S. Patent 5
859 520, 1999.
[4] J. Shao, D. Nolan, M. Teissier, and D. Swanson, ‘‘A novel
microcontroller-based sensorless brushless dc (BLDC) motor drive for
automotive fuel pumps,’’ IEEE Trans. Ind. Appl., vol. 39, pp. 1734–1740,
Nov./Dec. 2003.
[5] G. J. Su and J. W. McKeever, ‘‘Low-cost sensorless control of
brushless dc motors with improved speed range,’’ IEEE Trans. Ind.
Applicat., vol. 19, pp. 296–303, Mar. 2003.
[6] R. C. Becerra, T. M. Jahns, and M. Ehsani, ‘‘Four-quadrant sensorless
brushless ECM drive,’’ in Proc. 6th Annu. Applied Power Electronics
Conf. Exposition, Mar. 1991, pp. 202–209.
27
Department of Electrical Engineering
Southern Taiwan University
References






[7] S. Ogasawara and H. Akagi, ‘‘An approach to position sensorless drive
for brushless dc motors,’’ IEEE Trans. Ind. Applicat., vol. 27, pp. 928–933,
Sept./Oct. 1991.
[8] Y. S. Lai, F. S. Shyu, and Y. H. Chang, ‘‘Novel loss reduction
pulsewidth modulation technique for brushless dc motor drives fed by
MOSFET inverter,’’ IEEE Trans. Power Electron., vol. 19, no. 6, pp.
1646–1656, 2004.
[9] Y. S. Lai, F. S. Shyu, and Y. H. Chang, ‘‘Novel pulse-width modulation
technique with loss reduction for small power brushless dc motor drives,’’
in Conf. Rec. IEEE IAS Annu. Meeting, 2002, pp. 2057–2064.
[10] Tokyo Shibaura Electric Co., ‘‘Drive control apparatus for brushless
dc motor and driving method therefore,’’ U.S. Patent 5 491 393, 1996.
[11] Y. S. Lai, F. S. Shyu, and Y. K. Lin, ‘‘Novel PWM technique without
causing reversal dc-link current for brushless dc motor drives with
bootstrap driver,’’ in Conf. Rec. IEEE IAS Annu. Meeting, 2005, pp.
2182–2188.
[12] Y. S. Lai and Y. K. Lin, ‘‘A unified approach to back-EMF detection
for brushless dc motor drives without current and Hall sensor,’’ in Proc.
IEEE
IECON,
Nov.
2006, pp. 1293–1298.
Department
of Electrical
Engineering
Southern Taiwan University
28
References



[13] L6385: High-Voltage High and Low Side
Driver, ST Microelectronics Datasheet, USA, 1999.
[14] J. T. Strydom, M. A. De Rooij, and J. D. Van
Wyk, ‘‘A comparison of fundamental gate-driver
topologies for high frequency applications,’’ in Proc.
IEEE APEC, 2004, vol. 2. pp. 1045–1052.
[15] S. D. Sudhoff and P. C. Krause, ‘‘Operating
modes of the brushless dc motor with a 120
inverter,’’ IEEE Trans. Energy Conversion, vol. 5,
no. 3, pp. 558–564, 1990.
29
Department of Electrical Engineering
Southern Taiwan University
Thanks for your listening ！
2016/4/11
30
Department of Electrical Engineering
Southern Taiwan University
Robot and Servo Drive Lab.