dc otor & h bridge
DESCRIPTION
DC otor & H Bridge. 1. Outline. DC Motor. Principle Speed Control. H Bridge. Control Power. Figure 1. Real DC Motors. 2. Principle Recap. Figure 2. Lorentz Force Direction. Figure 3. Loop Current Diagram. http://hyperphysics.phyastr.gsu.edu/hbase/magnetic/magmom.html. 3. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/1.jpg)
DC otor & H Bridge
1
![Page 2: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/2.jpg)
Outline
DC Motor
Principle
Speed Control
H Bridge
Control
Power
Figure 1. Real DC Motors 2
![Page 3: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/3.jpg)
Principle Recap
•
Figure 2. Lorentz Force Direction
http://hyperphysics.phyastr.gsu.edu/hbase/magnetic/magmom.html
Figure 3. Loop Current Diagram
3
![Page 4: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/4.jpg)
Rotational Speed
commons.wikimedia.org Figure 4. Voltage and Full Speed Rotation
Figure 5. Macro View
Assume it is a 6V motor
6V+ -
+ -6V
4
![Page 5: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/5.jpg)
Rotational Speed
commons.wikimedia.org Figure 4. Reverse Voltage and Rotation
Figure 5. Macro View
Assume it is a 6V motor
6V+-
+- 6V
5
![Page 6: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/6.jpg)
Rotational Speed
commons.wikimedia.org Figure 4. Small Voltage and Slow Rotation
Figure 5. Macro View
Assume it is a 6V motor
4V+-
+- 4V
6
![Page 7: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/7.jpg)
Speed Control
PWM
% Duty Cycle
↓↓
% AVG Voltage
↓↓
% Speed http://forum.xda-developers.com/showthread.php?t=2542054
Figure 6. PWM Timing Diagram
7
![Page 8: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/8.jpg)
But…
Drive?
VCC: ~3.3V
Current: ~10mA
Backwards?
http://www.hennkwell.com.tw/products.php?func=p_detail&p_id=39&pc_parent=8
Table 1. Specification of DC Gear Motor
8
![Page 9: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/9.jpg)
Figure 7. H Bridge Diagram(http://en.wikipedia.org/wiki/H_bridge)
Table 2. H Bridge Functions (http://en.wikipedia.org/wiki/H_bridge)
H Bridge
9
![Page 10: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/10.jpg)
Figure 7. An H Bridge Diagram
Table 2. H Bridge Functions
10
H Bridge
![Page 11: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/11.jpg)
Figure 7. An H Bridge Diagram
Table 2. H Bridge Functions
11
H Bridge
![Page 12: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/12.jpg)
Figure 7. An H Bridge Diagram
Table 2. H Bridge Functions
12
H Bridge
![Page 13: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/13.jpg)
Figure 7. An H Bridge Diagram
Table 2. H Bridge Functions
13
H Bridge
![Page 14: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/14.jpg)
Figure 7. An H Bridge Diagram
Table 2. H Bridge Functions
14
H Bridge
![Page 15: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/15.jpg)
Figure 7. An H Bridge Diagram
Table 2. H Bridge Functions
15
H Bridge
![Page 16: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/16.jpg)
Figure 7. An H Bridge Diagram
Table 2. H Bridge Functions
16
H Bridge
![Page 17: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/17.jpg)
Figure 7. An H Bridge Diagram
Table 2. H Bridge Functions
17
H Bridge
![Page 18: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/18.jpg)
L298N Block Diagram
Figure 8. L298N Block Diagram (L298N Datasheet)
18
![Page 19: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/19.jpg)
L298N Block Diagram (Left Half)
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
19
![Page 20: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/20.jpg)
Four Switches in H Bridge
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
20
![Page 21: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/21.jpg)
H Bridge’s Shape
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Figure 7. H Bridge Diagram(http://en.wikipedia.org/wiki/H_bridge)
21
![Page 22: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/22.jpg)
Power Supply
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Figure 7. H Bridge Diagram(http://en.wikipedia.org/wiki/H_bridge)
22
![Page 23: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/23.jpg)
Logic Power Supply
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Figure 7. H Bridge Diagram(http://en.wikipedia.org/wiki/H_bridge)
23
![Page 24: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/24.jpg)
Inputs and Enable
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Figure 7. H Bridge Diagram(http://en.wikipedia.org/wiki/H_bridge)
24
![Page 25: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/25.jpg)
M
Outputs
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Figure 7. H Bridge Diagram(http://en.wikipedia.org/wiki/H_bridge)
25
![Page 26: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/26.jpg)
M
S1 S3
S2 S4
1
1
0
Functions
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Table 2. H Bridge Functions (http://en.wikipedia.org/wiki/H_bridge)
26
![Page 27: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/27.jpg)
M
S1 S3
S2 S4
1
0
1
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Functions
Table 2. H Bridge Functions (http://en.wikipedia.org/wiki/H_bridge)
27
![Page 28: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/28.jpg)
v M
S1 S3
S2 S4
0
X
X
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Functions
Table 2. H Bridge Functions (http://en.wikipedia.org/wiki/H_bridge)
28
![Page 29: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/29.jpg)
M
S1 S3
S2 S4
1
0
0
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Functions
Table 2. H Bridge Functions (http://en.wikipedia.org/wiki/H_bridge)
29
![Page 30: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/30.jpg)
M
S1 S3
S2 S4
1
1
1
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Functions
Table 2. H Bridge Functions (http://en.wikipedia.org/wiki/H_bridge)
30
![Page 31: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/31.jpg)
M
S1 S3
S2 S4
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Functions
Table 2. H Bridge Functions (http://en.wikipedia.org/wiki/H_bridge)
31
![Page 32: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/32.jpg)
M
S1 S3
S2 S4
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Functions
Table 2. H Bridge Functions (http://en.wikipedia.org/wiki/H_bridge)
32
![Page 33: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/33.jpg)
M
S1 S3
S2 S4
Figure 9. L298N Block Diagram (Left Half) (L298N Datasheet)
Functions
Table 2. H Bridge Functions (http://en.wikipedia.org/wiki/H_bridge)
33
![Page 34: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/34.jpg)
An example
Figure 10. 30mm DC Motor from Maxon
http://www.motioncontroltips.com/2013/05/06/30mm-dc-motor-from-maxon/
Figure 11. SN754410 Pin Connections (SN754410 Datasheet)
40V
GND
http://www.eecs.umich.edu/eecs/courses/eecs373/labsW14/lab6/index.html
Figure 12. SmartFusion FPGA
34
![Page 35: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/35.jpg)
What if we want to use a large-powered motor?
Figure 10. 30mm DC motor from maxon
http://www.motioncontroltips.com/2013/05/06/30mm-dc-motor-from-maxon/
Figure 13. L298N Pin Connections (L298N Datasheet)
50V
It will likely burn the H-bridge!
35
![Page 36: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/36.jpg)
Voltage Constraint (L298N)
• DC voltage cannot exceed H-bridge voltage constraint
https://www.sparkfun.com/datasheets/Robotics/L298_H_Bridge.pdf
Table 3. Voltage Constraint for L298N
36
![Page 37: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/37.jpg)
Power Constraint (SN754410)
http://www.ti.com/lit/ds/symlink/sn754410.pdf
Table 4. Voltage Constraint for SN754410
37
![Page 38: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/38.jpg)
What if we want to use that large-power DC motor?
Build an H-bridge with 4 switches!
38
![Page 39: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/39.jpg)
Which switch shall we use?
http://www.eeweb.com/electronics-forum/how-this-h-brigde-is-working
VS
http://www.youtube.com/watch?v=A_JNjAFo1f4&list=PLXrSeSVAb819HfhysOtYMdwDg3CTKXi6B
• MOSFET (Metal–Oxide–Semiconductor Field-Effect Transistor)Good for high current operation
• BJT (Bipolar Junction Transistor)Easier to build, use less circuitaryGood for low current operation
Figure 14. H-bridge with BJT Figure 15. H-bridge with MOSFET
39
![Page 40: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/40.jpg)
What is BJT?
http://fourier.eng.hmc.edu/e84/lectures/ch4/node3.html
What is MOSFET?
http://robertdick.org/eecs312/lectures/dic-l5.pdf
NMOS – active high
PMOS – active low
PNP – active low
NPN – active high
Choose voltage/current wisely on gate/base
Don’t need to know
40
![Page 41: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/41.jpg)
How to use BJT?
http://blog.oscarliang.net/bjt-bipolar-junction-transistor-beginner-tutorial/
Figure 16. BJT Model
http://www.eeweb.com/electronics-forum/how-this-h-brigde-is-working
Figure 17. H-bridge with BJT
B
C
E
41
![Page 42: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/42.jpg)
How to use MOSFET?
http://airsofttutorials.com/tutorials/diy-mosfet.html
Connect PMOS to Vcc, NMOS to ground
http://www.youtube.com/watch?v=A_JNjAFo1f4&list=PLXrSeSVAb819HfhysOtYMdwDg3CTKXi6B
Figure 19. H-bridge with MOSFETFigure 18. MOSFET Model
PMOS
NMOS
42
![Page 43: DC otor & H Bridge](https://reader036.vdocuments.us/reader036/viewer/2022062301/5681303e550346895d95d97a/html5/thumbnails/43.jpg)
ReferenceDC Motor:
Basic Principle:
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/motdc.html
http://en.wikipedia.org/wiki/DC_motor
Speed Control with PWM:
http://www.youtube.com/watch?v=NqqgbS3KXz0
Shaft Encoder
https://www.anaheimautomation.com/manuals/forms/magnetic-encoder-guide.php
H Bridge
http://en.wikipedia.org/wiki/H_bridge
L298N Datasheet:
https://www.sparkfun.com/datasheets/Components/General/L298N.pdf
SN754410 Datasheet:
http://www.ti.com/lit/ds/symlink/sn754410.pdf
43