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Day15 BLDC Motor Control implemented on matlab simulation.pptx
- 1. MATLAB SIMULINK 30 DaysMaster Class PMBLDC Motor Speed Control DAY 15
- 2. TABLE OF CONTENTS Introduction DCVs BLDC Working Principle Demo Project Idea Applications 01 02 03 04 05 06
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- 4. Brushed DC Commutation ●The windings in the armature are switched to the DC power by the brushes and armature ● Each winding sees a positive voltage, then a disconnect, then a negative voltage ● The field produced in the armature interacts with the stationary magnet, producing torque and rotation + - N S U + - U
- 5. DC Motor Bridge ●The DC motor needs four transistors to operate the DC motor ● The combination of transistor is called an H-Bridge, due to the obvious shape ● Transistors are switched diagonally to allow DC current to flow in the motor in either direction ● The transistors can be Pulse Width Modulated to reduce the average voltage at the motor, useful for controlling current and speed 0 1 1 1 0 0 0
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- 7. Three-Phase Bridge toDrive BLDC Motor ● The Brushless DC motor is really a DC motor constructed inside-out, but without the Brushes and Commutators ● The mechanical switches are replaced with transistors ● The windings are moved from the armature, to the stator ● The magnet is moved from the outside to become the rotor N S N S U V W
- 8. Six-step Commutation STEP1 STEP2STEP3 STEP4 STEP5 STEP6 STEP1 STEP2 STEP3 U V W U V W
- 9. Hall Sensors H1 H2 H3 Hall Sensorsdetect magnetic fields, and can be used to sense rotor angle The output is a digital 1 or 0 for each sensor, depending on the magnetic field nearby Each is mounted 120-degrees apart on the back of the motor As the rotor turns, the Hall sensors output logic bits which indicate the angle N S H1 H2 H3
- 10. Hall Sensor Commutation H1 H2 H3 STEP1STEP2 STEP3 STEP4 STEP5 STEP6 STEP1 STEP2 STEP3 U V W The combination of all three sensors produce six unique logic combinations or steps These three bits are decoded into the motor phase combinations
- 11. 3-Phase PWM U V W We candivide up the phase data into individual transistor gate signals Now we can see how we can modulate one transistor at a time to regulate the motor voltage, and also the speed UP UN VP VN WP WN
- 12. Brushless DC MotorBEMF ● The Back-EMF is the voltage generated in stator windings as the rotor moves ● BEMF voltages are more or less sinusoidal (depending on the motor) and are symmetrical from phase to phase ● We detect the zero crossings of each phase to commutate ● The motor MUST be moving to generate BEMF voltages
- 13. Types of BLDCMotor based on Magnet Arrangement 1.One Pole Pair 2.Two Pole Pair 3.Four Pole Pair
- 14. Parameters Brushed DCmotor Brushless DC motor Commutation It uses brushes to deliver current to the motor windings through mechanical commutation It uses Electrical commutation to deliver the current. Speed range Lower compared to BLDC High- because of the absense of brushes and commutator Control Simple Complex and expensive Electrical noise Arcs in the brushes generate noise Low Rotor inertia Higher rotor inertia which limits dynamic characterstics Low, because it has permnent magnets on rotar. it increses dynamic response speed/torque characteristics Low-mechnical limitation by brushes Higher-no mechanical limitations Life Short Long Building cost Lower compare to BLDC Higher- since it has permanent magnets Control requirment No controller is required Controller is always required to keep motor running Construction Armature winding is on rotar; Fixed magnets are placed on either side of the rotating electromagnet Armature winding is on stator and fixed magnets are on rotar Applications Home appliances, kid toys, in industrial applications, medical equipments, Electric vehicles, hybrid vehicles, and electric bicycles, Industrial
- 15. BLDC Motor SpeedControl Speed Command Pulse Width Modulator Transistors Motor Load
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- 17. Steps ●Identification of MotorTerminals ●Truth Table ●Switching Pattern ●Choosing of Drivers ●Design of Inverter ●Choosing of Controllers ●Software development
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- 19. Hall Sensor Commutation H1 H2 H3 STEP1STEP2 STEP3 STEP4 STEP5 STEP6 STEP1 STEP2 STEP3 U V W The combination of all three sensors produce six unique logic combinations or steps These three bits are decoded into the motor phase combinations
- 20. Expanding BLDC MotorControl Applications AC, DC and Universal Motors Transition to BLDC As consumers demand more energy efficient products, more BLDC motors are being used.
- 21. Project Research ● SpeedControl - Open Loop ● Speed Control - Closed Loop ● Speed Control - Closed Loop Sensorless
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- 27. ● BLDC SPECIFICATION ○Power : 60W ○ Voltage : 24V ○ Speed : 3000 RPM
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