sohaib hasan - brushless dc motors
DESCRIPTION
goodTRANSCRIPT
![Page 1: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/1.jpg)
Brushless DC Motors
Sohaib Hasan
![Page 2: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/2.jpg)
Motor Basics• What is a motor
– Converts electrical energy into kinetic energy
• Where did it come from– Identification of rotating magnetic field principle
by Nicola Tesla in 1882– Introduction of Electric Motor by Nicola Tesla in
December 1889 (U.S. Patent 0416194)
![Page 3: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/3.jpg)
Parts of a Motor1. End Bell Fastners2. Shaft Key & Keyways3. Bearing & Brushings4. End Ball Flanges5. Identification Plates6. Wire Warnish7. Commutators8. Brush Holders9. Laminations10. Conduit Connection Box11. Magnets (Ferrites)
Brushless Motor Components
Brush Type Motor Components Images courtesy of Hernon Adhesives & Sealents (http://www.hernonmfg.com/electricmotor.htm)
![Page 4: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/4.jpg)
Parts of a Motor
Images courtesy of How Stuff Works(http://electronics.howstuffworks.com/motor3.htm)
![Page 5: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/5.jpg)
How It Works• When electric current passes
through a coil in a magnetic field, the magnetic force produces a torque which turns the motor.
• Force in Motor:F=ILBF = Force B = Magnetic FieldL = Length of ConductorI = Current in Conductor
• Torque in Motor:T = IBA sin θA = LWL = Length of WindingW = Width of Winding
Images courtesy of Wikipedia(http://en.wikipedia.org/wiki/Electric_motor)
![Page 6: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/6.jpg)
Motor Types
AC Hybrid
E lectr icMo to r
DC
Induct ion S ynchrono us Compound PermanentMagnetS eriesS hunt Brush less
DCV ariable
Frequency S teppersS ync hronousPhase Loc ked
Loop
Po lyphas e S ingle Phas e
W oundRoto r S quirrel Cage S haded Po le Capacito r
C a p a c i t o r St a r t
P e rm a n e n t Sp l itC a p a c i t o r
T wo C a p a c it o r
S ingle /Po lyphase
W o un d F ie ld
P e r m a n e n t M a gn e t
R e luc t a n c e
H y st e r e sis
M ult ip le Sp e e dP o le Sw it c h in g
AC- DC S plit F ield
M o v in g C o il
B a sk e t W e a v e
D C T o rq u e r
C o n v e n t io n a lC o n st ruc t io n
InverterD riven
Elec t ronicCommunic at ion S ynchrono us Induction
W o un d R o t o r
P e rm a n e n t M a g n e t
St a t o r C o n t r o l
R o t o r C o n t r o l
Reluctance PermanentMagnet S mall Angle
R e luc t a n c e
P e r m a n e n tM a gn e t
![Page 7: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/7.jpg)
Brushless DC Motor
• No Commutators
• Position of Coils with respect to the magnetic field is sensed electronically.
• Current is commutated through electronic switches to appropriate phases.
![Page 8: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/8.jpg)
How it Works
• Halls Sensors sense the position of the coils
• The Decoder Circuit turns appropriate switches on and off
• The voltage through the specific coils turns the motor
Images courtesy of Servo Magnetics(http://www.servomag.com/flash/2-pole/2pole-bldc-motor.html)
![Page 9: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/9.jpg)
Advantages• Increased Reliablilty & Efficiency
• Longer Life
• Elimination of Sparks from Commutator
• Reduced Friction
• Faster Rate of Voltage & Current
• Precision Voltage & Current Applied to Field Coils
![Page 10: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/10.jpg)
Applications• Low Power
– Consumer Electronics– Medical Field
• High Power– Industrial Machinery– Vehicles – Airplanes
![Page 11: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/11.jpg)
Disadvantages• Requires Complex Drive Circuitry
• Requires additional Sensors
• Higher Cost
• Some designs require manual labor (Hand wound Stator Coils)
![Page 12: Sohaib Hasan - Brushless DC Motors](https://reader036.vdocuments.mx/reader036/viewer/2022081505/577cc68d1a28aba7119e9469/html5/thumbnails/12.jpg)
Useful Links• http://en.wikipedia.org/wiki/Electric_motor
• http://electronics.howstuffworks.com/motor3.htm
• http://www.hernonmfg.com/electricmotor.htm
• http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
• http://www.servomag.com/flash/2-pole/2pole-bldc-motor.html
• http://www.engineersedge.com/motors/brushless_dc_motor.htm
• http://www.freescale.com/webapp/sps/site/application.jsp?nodeId=02nQXGrrlPY7r803B5