Intro to Motor and Motor Control
Garrick Dai
Motor Drive FAE
TI SEMI Shenzhen Branch
Direct: 0755-26007816
Mobile: 13501566540
Email: Garrick-dai@ti.com
Apr 2012
1. Motor applications
马达的应用
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1.1 Used in industrial machinery 1
Vending machine
Currency equipment
Card feeder
H-Bridge
Bill Validate
H-Bridge
Bill Validate
H-Bridge
Industrial
Industrial
equipments
equipments
Slot machine
Security camera
Projector
Drum
Stepper
Coin hopper
H-Bridge
Fan
H-Bridge
IRIS,zoom,tilt
Stepper
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AF/zoom
Stepper
1.2 Used in industrial machinery 2
Textile machine
Gate opener
Feeder
H-Bridge
Antenna
positioning
Door motor
H-bridge/BLDC
Stage lighting
Industrial
Industrial
equipments
equipments
CPAP
Angle
Stepper
Positioning
motor
Stepper
Pump
H-bridge/ BLDC
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1.3 Used in office appliances
The motors inside the movement
LBP
PPC
Drum
Brushless
ADF
Mirror
Stepper
Brushless
ADF
Stepper
Stepper
Mirror
Brushless
Drum
OA
OA
equipments
equipments
MFP
F/B (Flat bed)
Stepper
Lift
H-Bridge
Scanner
Head drive
Stepper
ADF
Stepper
Stepper :Stepping motor driver, Brushless :3phase brushless motor driver, H-Bridge :Brush motor driver
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1.4 Used in home appliances
Air-conditioner
Dish washer
Drainage Pump
Brushless
Home
Home appliance
appliance
Refrigerator
Ventilator
Fans
Fans
Brushless
Sewing machine
Bobbin
H-Bridge
Brushless
Dumper
Stepper
Brusless
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Main
H-Bridge
Cloth feeder
Stepper
1.5 Used in battery-powered devices
Toy（IR car）
Toy (Toy robot)
Drive
Articulation drive
H-Bridge
H-Bridge
Battery-powered
Battery-powered
appliance
appliance
AF
H-Bridge
Stepper
ＩＲＩＳ
H-Bridge
Stepper
DSC
Shutter
H-Bridge
Zoom
H-Bridge, Stepper
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2. DC Motor basic principle
直流马达原理
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2.1 AC motor and DC motor
Motor control just for DC motors ! (Not for AC motors)
AC
power
supply
AC socket
phase
phase
shift
shift
AC socket
×
Apply AC power supply to the
motor directly.
No MCD for AC motor!
DC
power
supply
Vcc
AC-DC
AC-DCconverter
converter
(transformer
(transformer))
GND
＋
－
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○
MCD/MCU
2.2 DC motor speed control
・阻抗控制
Ｍ
可変抵抗器
Heat generated
・PWM控制
On
Switching method
Ｍ
Off
1周期
电圧＝最大值×
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ON時
ON時
周期
2.3 Single phase AC and three phase AC
单相交流
2
1.5
1
0.5
0
-30
0
30
60
90
120
150
180
210
240
270
300
330
360
0
-30
0
-0.5
30
60
90
120
150
180
210
240
270
300
330
360
-0.5
-1
-1.5
-2
三相交流
相電圧
2
1.5
1
線間電
圧
0.5
-1
-1.5
-2
中线电流为0
（可省略）
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三相交流波形 (各相
各相之和为
各相之和为0)
之和为
2.4 Which kind of DC motors?
There are 4 kinds of DC motors….
Brush
Brush motors
motors
Feature
Cheap
Stepping
Stepping motors
motors
Convenient
Brushless
Brushless motors
motors
High
precision
DC motors
Linear
Linear motors
motors
（（actuators
actuators））
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High
precision
2.5 Motor basic principle
son
Ｐｏｉｎｔ Les
The motor is rotated by a magnet, whose power is
generated using a coil.
Magnet (rotor)
Ex.
Ｎ
Ｓ
Ｎ
Ｓ
Ｎ
N pole → S pole
repulsion against S pole,
attraction towards N pole
Coil (stator)
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When the coil current changes
direction from→ to → , the
magnet poles flip, which
moves the magnet to the next
position.
3. DC brushed motor
直流有刷马达
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3.1 This is the DC brushed motor
Brushed
Brushed motors
motors
[How to drive]
Commutator
Brush
Stator
Rotor
The motor is constituted rotor and stator.
1) By bringing the brush into contact with
the commutator, current flows from the
positive of the battery to the negative via
the commutator, the brush and a coil.
2) As the commutator rotates, the coil to be
electrified switches. Repeating this
operation rotates the motor.
Battery
[Features]
current flow
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<Pros>
* Low price
<Cons>
* Large brush noise, limited life
time of the brush
3.2 H-bridge driver
”Bridge driver” （calls it “H-bridge”）
4 power transistors/FETs inside
1 H-bridge
What the bridge driver IC can do
VM
VM
Motor
* Can drive the motor in CW, CCW, stop
and brake modes.
* Can change the motor rotation direction.
GND
GND
* Can control motor speed by PWM
operation or same kind of circuit.
CW
CCW
Tr. ON
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4. DC Stepping motor
直流步进马达
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4.1 This is stepping motor
[How to drive]
Stepping
Stepping motors
motors
Current
direction
control
A phase
①As the current flows into the coil, the rotor
magnet is repulsed, creating a magnetic
field.
②The rotor moves when this magnetic field
reverts.
Stator
[Features]
Rotor
N
S
S
Current
direction
control
B phase
N
<Pros>
Easy open loop control
+ Easy driving at low speed
<Cons>
Difficult to drive at high speed
Current
direction
control
B phase
A phase
Magnet moves step by step !
Current
direction
control
Ex) 2phase bipolar type
N
S
N
S
N
Ｓ
Ｎ
Ｓ
Ｎ
Ｓ
Ｎ
Ｎ
Ｓ
Ｓ
Ｎ
Ｎ
Ｓ
Ｎ
Ｓ
Ｓ
Ｎ
Ｓ
CW
CCW
A phase
B phase
A phase A phase B phase A phase B phase A phase
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4.2 Stator-Rotor Tooth Alignment
A
Whole Step
B
48 Stator Teeth
Unaligned
B
50 Rotor Teeth
(1.8o Rotor Movement)
S
A
Half Step
(0.9o Rotor Movement)
Aligned
North Pole
B
South Pole
B
A
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A
4.3 Stepping motor control
8 power transistors inside! 2 H-bridges
(2 phase bipolar type)
VM
VM
What the stepping motor driver IC can do.
Motor
* Can drive the motor in CW, CCW and
stop modes.
* Can keep stopping the motor in one
position.
* Can control how many angle to move
the motor.
A phase
B phase
Ex) CW mode
GND
GND
+Io
Io(A)
+ Io
- Io
Tr. ON
-Io
+Io
Io(B)
-Io
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t [s]
4.4 Stepper motor control
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4.5 Unipolar type and Bipolar type
There are 2 kind of type for stepping motor as following.
●Unipolar type ：Uni-directional current through the coil
●Bipolar type ： Bi-directional current through the coil
Motor
Motor
Unipolar type
Bipolar type
S
N
N
S
S
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N
N
S
4.6 Unipolar VS Bipolar
Type
Unipolar
Bipolar
System
Feature
One-way current onto the coil （active
drive on half of the wave）
）
Number of power transistors is half of bipolar type
Current is flown both ways onto the coil
（Full-wave drive）
）
Magnet power has to be 2 that of unipolar.
Angular precision is easy to obtain.
[Unipolar type】
[Bipolar type]
VM
VM
Motor
Motor
Motor
GND
Motor
GND
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4.7 Micro step drive ( realized by external DAC)
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4.8 Micro Step vs Full Step
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5. Three phase DC brushless
motor (BLDC)
3相直流无刷马达
相直流无刷马达（
）
相直流无刷马达（简称BLDC）
简称
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5.1 This is the brushless motor (BLDC)
Brushless
Brushless motors
motors
No brush like brushed motor Brushless
Use hall elements Hall motor
Not use hall elements Sensorless motor
N
S
S
N
N S
son
1Point les
Rotor
S
N
Hall elements
The element which outputs voltage under
magnetism.
Hall element
C phase
B phase Stator
[How to drive]
A phase
Hall elements
e
has
p
C
B ph
ase
[Features]
Hall element
Hall element
A phase
Hall signals
1) Senses rotor position by hall elements,
then transfers it to the IC.
2) Operates 3 hall signals, then electrifies
the motor coils to drive the motor
Outputs
<Pros>
*) High reliability due to no mechanical
contact, high speed drive
<Cons>
*) High motor cost (mainly magnet)
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5.2 BLDC structure
Ex.） Capstan motor for VCR
Magnet!
Hall elements
Coil
Rotor
stator
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5.3 BLDC control (120° inverter with sensor)
Upper phases: u, v, w, Lower phase:x, y, z.
What the brushless motor driver IC can do.
VM
VM
Motor
* Can drive the motor in CW, CCW, stop
and brake modes.
* Can control motor speed by optional
circuit.
Ha
GND
GND
A-phase
B-phase
Matrix
circuit
+
Hb
Ex) CW mode
Hc
C-phase
Hall signals
Hall
signals
−
－
VM
GND
－
VM
Output GND
voltage
VM
GND
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La
Lb
Lc
6. Sensored and sensorless
BLDC rectangular wave
(120°
°inverter) control
有/无传感器直流无刷马达
无传感器直流无刷马达
方波120度变频控制
度变频控制
方波
Return
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6.1 Single phase inverter theory
③
②
①
Ideal sine
waveform
③
①
②
②
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①
Actual
rectangular
waveform
6.2 Rectangular wave and sine wave
Variable duty PWM
Fixed duty PWM
ＰＷＭ carrier
电压波形
电流波形
正玄波
矩形波
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6.3 Rectangular wave( 120° inverter ) control
: motor coil
１
U
４
W
U
W
V
２
U
V
５
W
U
W
V
３
U
V
６
U
W
W
V
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V
6.4 Rectangular wave control diagram
： phase current
DC280V
u
v
w
ON
AC100V
x y z
U
V
ON
１：ｕ→ｙ ２：ｕ→ｚ ３：ｖ→ｚ
４：ｖ→ｘ ５：ｗ→ｘ ６：ｗ→ｙ
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W
U
④①
V
②⑤
③
⑥
W
6.5 Sensored BLDC control
1
Controller
2
A
12 zones in 360 degrees
of mechanical rotation
B
s
3
4
C
r
t
5
6
1
1
0
Source: Eastern Air Devices, Inc. Brushless DC Motor Brochure
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6.6 Timing chart for sensored BLDC by S/W
Drive signal
(Low active)
0
U1
U1, V1, W1,
DC
_U1, _V1,
U, V, W
_W1
Power
Powerdriver
driver
MCU
MCU
PWM
PWM
_U1
M
V1
_V1
PDU, PDV, PDW
W1
_W1
Terminal voltage
U
V
W
Position signal
PDU
PDV
PDW
Position detection
Commutation
Sampling start
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60
120
180
240
300
360
420deg
Conditioning
Controller
6.7 Sensorless BLDC control
Source: Eastern Air Devices, Inc. Brushless DC Motor Brochure
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6.8 Timing chart for sensorless BLDC by S/W
Drive signal
U1, V1, W1,
_U1, _V1, _W1
U, V, W
Position
Positionsignal
signalcircuit
circuit
PDU,
PDV,
PDW
-60
U1
Power
Power
driver
driver
MCU
MCU
PWM
PWM
(Low active)
DC
M
V1
Rx
+
Ref. V
_U1
Ry
_V1
W1
_W1
Terminal voltage
U
V
W
Position signal
PDU
PDV
PDW
Position detection
Commutation
Sampling start
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0
60
120
180
240
300
360
420deg
7. Sensored BLDC sine
wave(180°
°inverter) control
有传感器直流无刷马达正玄波
180度变频控制
度变频控制
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7.1 Sine wave (180° inverter) control
DC 310V
u v w
U
AC220V
u
x y z
Ｖ相电压
Ｕ相电压
w
V W
v
u
Ｗ相电压
w
v
2
1.5
1
1.5
0.5
1
0
0
30
60
90
120
150
180
210
240
270
300
330
360
0.5
-0.5
-1
-1.5
0
0
-0.5
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30
60
90
120
150
180
210
240
270
300
330
360
7.2 Sine wave PWM waveform
3
2.5
Ｕ相data
2
Ｖ相data
1.5
W相data
1
0.5
0
0
30
60
90
120
150
180
210
Ｕ上相
Ｕ下相
Ｖ上相
Ｖ下相
Ｗ上相
Ｗ下相
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240
270
300
330
360
7.3 Sine wave phase voltage waveform
2
Ｕ相
1.5
Ｖ相
1
W相
0.5
①
0
-30
0
30
60
90
120
150
180
210
240
270
300
330
360
U
-0.5
①
②
V
③
①
W
U
U
③
③
V
W
②
2
1.5
1
0.5
Ｕ-Ｖ线间电压
0
-30
0
30
60
90
120
150
180
210
240
270
300
-0.5
330
360
Ｖ-W线间电压
-1
W-Ｕ线间电压
-1.5
-2
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V
②
W
8. Sensored BLDC Vector
Inverter Control
有位置传感器的直流无刷
马达矢量变频控制
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8.1 Vector inverter block diagram (sensored)
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9. Sensorless BLDC Vector
Inverter Control
无位置传感器的直流无刷
马达矢量变频控制
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9.1 Vector inverter block diagram (sensorless)
This is only
difference to
sensored BLDC
vector inverter!
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~ The End ~
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