20-06-2012, 03:08 PM
SPEED CONTROL OF DC SHUNT MOTOR USINGMICROCONTROLLER
SPEED CONTROL OF.ppt (Size: 2.64 MB / Downloads: 115)
INTRODUCTION:-
Type of speed control of dc motor
simple speed control
Digital speed control
microcontroller speed control
DC motor speed controllers are very useful for controlling the motion of robotic and industrial automation systems. The controller presented here uses the PWM technique. The PMW wave for speed control is generated using Atmel AT89C51 microcontroller. To control the speed of the DC motor, you need a variable power supply. When the DC motor is switched on, it take the certain time to reach the full speed. As soon as the power supply is switched on, the DC motor starts gaining speed and if you switched off the power supply before it reaches the maximum rated speed, starts to slow down. In case of switching off are done in quick succession, the motor rotates sat allows speed between zero and full speed. This is what a PWM technique.
LM7805-Voltage Regulator IC:-
A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level. A voltage regulator may be a simple "feed-forward" design or may include negative feedback control loops. It may use an electromechanical mechanism, or electronic components. Depending on the design, it may be used to regulate one or more AC or DC voltages.
Resistors
R1, R4, R5 - 1Koms - Brown, Black, Red, Golden
R2 - 8.2oms - Grey, Red, Red, golden
R3 - 3.30oms - Orange, Orange, Brown, Golden
RM1 -4.7Koms -Resistor Network
Capacitor
C1 -1000 microfarad /16V/25V-Electrolytic Cap
C2, C4 - 0.1 microfarad/100KPF -104 -Disk Type
C3 - 100 microfarad/25V- Electrolytic Cap
C5, C6 -33PF- Disk Type
C7 -10micro/50V- Electrolytic Cap
Common Anode Display:-
Excellent appearance
Evenly lighted segments
Gray package gives optimum contrast
Wide viewing angle
Dc shunt motor:-
When a current-carrying conductor is located in an external magnetic field perpendicular to the conductor, the conductor experiences a force perpendicular to itself and to the external magnetic field.