design of VFD for speed control in single phase induction motor
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Transcript of design of VFD for speed control in single phase induction motor
Presented byLajin B S
Jiji PrabhashMeghana Jayakumar
Nithin JosephMalini Mohan
Guided by: Mr. Rahul R S
DESIGN OF VARIABLE FREQUENCY DRIVE
FOR SPEED CONTROL IN SINGLE PHASE INDUTION MOTOR
OVERVIEW OF PRESENTATION AIM INTRODUCTION FUNCTIONAL BLOCK DIAGRAM WORKING PRINCIPLE
CONTND… FIRST PHASE ADVANTAGES DISADVANTGES APPLICATIONS
AIM
Design of variable frequency drives for speed
control in single phase induction motor
PHASES OF PROJECT
FIRST PHASE
• Experimental set up of the drive using basic knowledge
SECOND PHASE
• Microcontroller programming
THIRD PHASE
• Hardware design, assembling & installation
INTRODUCTION Most of the industries use induction motors as the
drives Rising energy price create a need for energy efficient
motor VFDS are useful in energy saving It reduces the motor speed as demand decreases VFDs consists of Electronic actuator-controller Driving electrical machines – motor Driven machine – pump, fan, blower…
FUNCTIONAL BLOCK DIAGRAM
WORKING PRINCIPLE
Torque of IM depends on flux
Flux α V/f ratio
Hence torque α V/f ratio
Speed = 120 * f/ P
With load change, speed also changes
By retaining V/f ratio constant, torque is
maintained
TORQUE SPEED CHARACTERISTICS OF IM
Serving as the prime power sources for a seemingly
limitless array of small-horsepower applications in
industry and in the home.
Single phase AC electrical supply is what is typically
supplied in homes, three phase electrical power is
commonly only available in a factory setting.
Correctly sized and rated -- can last a lifetime with little
maintenance.
WHY SINGLE PHASE INDUCTION MOTOR?
PWM INVERTERS? Characterized by constant amplitude pulses Width of these pulses is modulated Different PWM techniques – Single pulse
modulation, Multiple pulse modulation and
Sinusoidal pulse modulation These techniques differ each other in harmonic
content Choice – on permissible harmonic content in
input
SINUSOIDAL PULSE WIDTH MODULATION Pulses over half cycle of unequal widths are generated Pulse width is a sinusoidal function of angular position of each cycle By comparing a sinusoidal wave against a triangular carrier wave Simple and ease of implementation No: of cycles is decided by ratio of triangular carrier frequency to that of modulating sinusoidal frequency
WAVEFORMS
CONTND…
PWM inverter model has four sections
o Power supply section
o Power circuit section
o Load circuit section
o Gate control section
BASIC CIRCUIT
HARDWARE
Bridge Rectifier
DC Chopper
PIC Microcontroller
Basic circuit
Keypad & LCD Connection
Dead Band time Generator
3-Phase Bridge Driver
IGBT 3-Phase Inverter
COMPONENTS Diode rectifier- KBPC 35-10, Maximum recurrent
peak reverse voltage 1000 V. Maximum average forward rectified current 35 A
Supply source – 220V, 50 Hz ac Power circuit section – 4 No: of 2MBI50L-120
IGBTs, 1200V, 50 A,400 watts, Vgth > 20V Load circuit section –single phase induction motor Gate control section- PIC 16F877A, 5V Gate driver – IR21363, Gate drive supply
voltage 10-20V
EXPERIMENTAL SETUP
Software used- PROTEUS Microcontroller – 8051
PROGRAMORG 0000HST:JNB P1.0,A1JNB P1.1,A2JNB P1.2,A3JMP STA1:CLR P2.0CALL DELAY1SETB P2.0CALL DELAY1JNB P1.1,A2JNB P1.2,A3JMP A1DELAY1:
MOV R0,0FHL1:MOV R1,0FFHDJNZ R1,$DJNZ R0,L1RETA2:CLR P2.0CALL DELAY2CALL DELAY1SETB P2.0CALL DELAY2CALL DELAY1JNB P1.0,A3JNB P1.2,A1
CONTND…
JMP A2DELAY2:MOV R0,0FHL2:MOV R1,0FFHDJNZ R1,$DJNZ R0,L2RETA3:CLR P2.0CALL DELAY3CALL DELAY1CALL DELAY3CALL DELAY1CALL DELAY2
CONTND…
SETB P2.0CALL DELAY3CALL DELAY3CALL DELAY1CALL DELAY2CALL DELAY1JNB P1.0,A1JNB P1.1,A2JMP A3DELAY3:MOV R0,03FHL3:MOV R1,0FFHDJNZ R1,$DJNZ R0,L3RETEND
CONTND…
ADVANTAGES Rising energy prices creates a need for energy
efficient motor To reduce energy losses we select VFDs Improved operating performance Good control capability Efficient energy saving Consume less energy
DISADVANTAGES
High cost System resonance Increased noise& vibration Shortens life Reduce service factor
APPLICATIONS Boiler pumps , fans& HVAC system Cooling towers Compressors Stairway & packing ventilation Kitchen hoods Roof top units Air handlers Elevators & escalators
THANK YOU