SPEED CONTROL OF BLDC MOTOR USING PI CONTROLLER J.PHANEENDRA(10261A0219) K.ASHA(10261A0221) C.SRAVAN KUMAR(10261A0210)

CONTENTSINTRODUCTIONWORKING OF MOTORBRUSHLESS MOTORWORKING OF BLDCSPEED CONTROL USING PI CONTROLLERDESIGN OF PI CONTROLLERADVANTAGES OF BLDC MOTORAPPLICATIONSCONCLUSION

INTRODUCTIONWhat is Motor?It is a machine can converts electrical energy to mechanical energy.It may be DC or AC depending upon the type of power supply.It has mainly two parts- stator & rotor.DC motors are of two types-Brushed motor with brushes and commutator andBrushless motor- without brushes.

INTRODUCTIONWhat is commutator and brush ?

Commutator is a cylindrical in structure, made of copper or carbon with high conductivity.Mounted on the rotor part of the brushed motor.Helps to conduct current through conductor when the brushes comes to contact during rotation.The electrical contacts to the rotating ring called brushes.

General physics of motor

Working Principle

Working Principle

History of BLDC motorsThis BLDC motor was came into this world in 1962 by .G. Wilson and P.H. Trickey and they called as "a DC machine with solid state commutation." Later at the end of the 1980s, Robert E. Lordo unveiled the first large brushless DC motors, which had at least ten times the power of the earlier brushless DC motors

BRUSHED DC MOTOR

BRUSHLESS DC MOTOR

BRUSHLESS DC MOTORBrushless DC Motor is also known as electronically commutated motor or synchronous motor.It has no brushes and commutators.The rotation of the rotor depends on the accurate position with stator.BLDC motors are two types. They are 1.sensored BLDC Motor 2.sensorless BLDC Motor

CONSTRUCTION OF BLDC MOTORBLDC motors have many similarities to AC induction motors and brushed DC motors in terms of construction and working principles.Parts of the brushless dc motor are 1.stator2.rotor

STATOR

STATORThe BLDC motor stator is made out of laminated steel stacked up to carry the windings. Windings in a stator can be arranged in two patterns; i.e. a star pattern (Y) or delta pattern ().The major difference between the two patterns is that the Y pattern gives high torque at low RPM and the pattern gives low torque at low RPM.

ROTOR

ROTORThe rotor of a typical BLDC motor is made out of permanent magnets. Depending upon the application requirements, the number of poles in the rotor may vary. Another rotor parameter that impacts the maximum torque is the material used for the construction of permanent magnet.

Working of BLDC motorAs there is no commutator ,the current direction of the conductor on the stator controlled electronically.Rotor consists the parmanent magnet where as stator consist a no. of windings. Current through these winding produces magnetic field and force.Hall sensor used to determine the position during commutation.

Commutation of BLDC motorBrushless DC motor requires external commutation circuit to rotate the rotor.Rotor position is very important.HALL SENSOR senses the position of the coil accurately

SPEED CONTROL USING PI CONTROLLERThe combination of proportional and integral terms is important to increase the speed of the response and also to eliminate the steady state error.PI controller will eliminate forced oscillations and steady state error resulting in operation of on-off controller and P controller respectively

DESIGN OF PI CONTROLLER

Advantages of Brushless MotorIn BLDC motor PM are on the rotor & electromagnets are on the stator controlled by software. Thus the advantages are:

Because of computer control it is more precise & more efficient.There is no sparking & less electrical noise.Voltage and current rating is high.High speed can be achieved.As there is no brushes it requires no servicing.It has longer life.Low Radio Frequency Interference and Electromagnetic Interference.

APPLICATIONSAUTOMATION APPLICATIONS1.HVAC2.CEILING FANS3.SMALL ELECTRIC VEHICLE4.ELECTRONIC POWER STEERINGINDUSTRIAL APPLICATIONS1.LINEAR MOTORS2.SERVO MOTORS3.LOW VOLTAGE SOLAR WATER PUMPS

CONCLUSION we can conclude that speed of the BLDC motor can be controlled by using the PI CONTROLLER because of its different applications in industries and where there is a need of variable speed aplications.