The document discusses Brushless Direct Current (BLDC) motors. It describes BLDC motors as electronically commutated motors that do not use brushes, instead using electronic switching circuits. The construction of a BLDC motor is explained, including its stator, rotor, and position sensors. The working principle is also summarized, noting that the rotor's position is sensed to electronically commutate the winding sequence. Advantages over brushed DC motors include higher efficiency, longer lifetime, and noiseless operation. Applications mentioned include consumer goods, medical devices, and electric vehicles.

1. CSMSS CHH. SHAHU COLLEGE OF ENGINEERING AURANGABAD
TOPIC
Design Of BLDC Motor for electrical Vehicle

2. BLDC MOTORS
Brushless Direct Current Motors

3. CONTENT
 INTRODUCTION
 BRUSHLESS DC MOTORS
 CONSTRUCTION
 WORKING
 BLDC VS BDC
 ADVANTAGES & DISADVANTAGES
 APPLICATION
 CONCLUSION
 REFERENCES

4. INTRODUCTION
Brushless Direct Current(BLDC) motors are one of the motor types rapidly gaining popularity. BLDC
motors are used in industries such as Appliances, Automotive, Aerospace, Consumer, Medical,
Industrial Automation Equipment and Instrumentation. As the name implies, BLDC motors do not use
brushes for commutation: instead, they are electronically commutated. BLDC motors have many
advantages over brushed DC motors and induction motors. A few of these are:
 Better speed versus torque characteristics
 High dynamic response
 High efficiency
 Long operating life
 Noiseless operation
 Higher speed ranges

5. Brushless Permanent Magnet DC Motor
 Brushless DC electric motor also known as electronically
commutated motors (ECMs, EC motors) are synchronous
motors that are powered by a DC electric source via an
integrated inverter/switching power supply, which
produces an AC electric signal to drive the motor.
 Magnetic fields generated by the stator and rotor rotate
at the same frequency.
 No slip
 The stator consist of several coils which current is led
through creating a magnetic field that makes the rotor
turns.

6. CONSTRUCTION OF BLDC
It consist of two parts mainly Stator & Rotor.
STATOR
 Stator is made up of silicon steel stampings with slots.
 The slots are accommodated armature windings.
 This windings is wound with specified no of poles(even
number).
 This winding is connected with a power electronic
switching circuits (inverter circuits).

7. Rotor
 Rotor is of permanent magnet.
 No of poles on rotor is same as that of stator
 Rotor shaft carries a RPS (Rotor position Sensor) and it
provides information about the position of shaft at any
instant to the controller which sends signal to the
electronic commutator.
 The electronic commutator function is same as that of
mechanical commutator in DC motor.

8. WORKING OF BLDC MOTOR
 The rotor and stator of a BLDC motor are shown in the fig.
It is clear that, the rotor of a BLDC motor is a permanent
magnet.

9.  The Stator has a coil arrangement, as illustrated :
The internal winding of the rotor is illustrated in the figure as coil
wounded stator.

10.  By applying DC power to the coil, the coil will energize and become
an electromagnet.
 The operation of a BLDC is based on the simple force interaction
between the permanent magnet and the electromagnet. In this
condition, when the coil A is energized , the opposite poles of the
rotor and stator are attracted to each other (The attractive force is
shown in green arrows). As a result the rotor poles move near to the
energized stator.
A
B

11.  As the rotor nears the coil A and coil B is energized. As the
rotor nears coil B, coil c is energized. After that, coil A is
energized with the opposite polarity.
 This Process is repeated and the Rotor current continues
to rotate.

12. Improving The BLDC Performance
 Unlike a brushed DC motor, the commutation of BLDC motor is
controlled electronically.
 It is important to know the rotor position in order to understand which
winding will be energized following the energizing sequence.
 Rotor position is sensed by different ways some of them are:
1) Hall Sensors
2) Optical encoders

13. Hall Sensors
 When a magnetic field applied to a system with electric current a hall
voltage perpendicular to the field and to current is generated. This
was discovered by Edwin Hall in 1879.

14. Difference Between BLDC and BDC motor
Features Brushless DC Motor Brushed DC Motor
Commutation Electronic commutation based on Hall
position sensors
Brushed Commutation
Maintenance Less or No maintenance Periodic Maintenance
Life Longer Shorter
Speed/Torque Enable operations on all speed with
rated load
At higher speeds,
brush friction
increases and reduce
torque
Efficiency High Moderate
Speed Range Higher- No mechanical Limitation due
to contact
Lower- Mechanical
Limitations due to
brushes
Electric Noise Generation Low-Because it has permanent magnets
on the rotor, improves dynamic
response
Arcs in the brushes
will generate electric
noise

15. Advantages
 Increased Reliability & Efficiency
 Longer Life
 Elimination Of Sparks from commutator
 Reduced Friction
 Faster rate of voltage & current
Disadvantages
 Requires Complex Drive Circuitry
 Requires Additional Sensors
 Higher Cost
 Some designs Require manual labour (Hand wound stator coils)

16. Applications
 Consumer: Hard Drives, CD/DVD Drives, PC Cooling Fans,
Toys, RC airplanes, air conditioners
 Medical: Artificial heart, Microscopes, centrifuges,
Arthroscopic Surgical tools and Orphan transport pump
system
 Vehicles: Electronic power steering, personel electric
vehicles
 Airplanes: An electric self launching sailplane, flies with a
42kw DC/DC brushless motor and li-Ion batteries and can
climb up to 3000m with fully charged cells

17. TORQUE-SPEED CHARACTERISTICS

18. Reference
 Brushless DC electric motor- Wikipedia
 https://www.nxp.com/docs/en/application-note/AN12602.pdf
 https://cselectricalandelectronics.com/difference-between-bldc-and-pmsm-
motor-brushless-dc-motor/
 https://www.lesics.com/brushless-dc-motor.html
 https://www.nxp.com/docs/en/application-note/AN12602.pdf
 https://www.researchgate.net/figure/Speed-Vs-Torque-Characteristics-of-
BLDC-3_fig2_265991723

19. Thank You