09-05-2014, 04:57 PM
Modeling, Simulation and Implementation of Speed Control of DC Motor Using PIC 16F877A
Simulation and Implementation .pdf (Size: 1 MB / Downloads: 172)
Abstract
The Microcontroller based adjustable closed-loop
DC motor speed controller systems has already become an
important drive configuration for many applications across a
wide range of powers and speeds . This is due to their simple
control, high reliability, low cost and fast response. Control
System Design and Analysis technologies are widely suppress
and very useful to be applied in real-time development. Some
can be solved by hardware technology and by the advance
used of software, control system are analyzed easily.
Fractional HP DC Motors can be used in various applications
and can be used as various sizes and rates. The designed
circuit is stimulated using Real peak and MP LAB. In this
paper, control techniques of PIC 16F877A microcontroller
and MOSFET, mechanism assignments of analyzed by mainly
focusing with the “Modeling and Simulation of DC Motor
using MATLAB”.
INTRODUCTION
Traditionally, the DC Motors and the associate close
loop control systems used to drive them have been
modeled using classic control theory techniques, based on
transfer functions. Control system design and analysis
technologies are widely suppress and very useful to be
applied in real-time development. Some can be solved by
hardware technology and by the advance used of software,
control system are analyzed easily and detail. DC Motors
can be used in various applications and can be used as
various sizes and rates. The microprocessor computes the
actual speed of the motor by sensing the terminal voltage. It
then compares the actual speed of the motor with the
reference speed and generates a suitable control signal
which is fed into the triggering unit. This unit drives a
Power MOSFET amplifier, which in turn supplies a PWM
voltage to the dc motor.
SYSTEM DESCRIPTION
The input from the stable power supply unit (230 V AC)
is converted into 12v AC by means of a step down
transformer, the output of this is used as input to bridge
rectifier circuit. Here in this system bridge rectifier will
generate 5 V DC with the help of regulator 7805. The
output of the 7805 regulator is used as an input to the PIC.
The PIC will generate pulses to drive the DC motor
according to the requirement. As the output voltage of the
PIC is in mV, driver circuits are used to drive the DC motor
An optical encoder is used to measure the speed of the
motor. The output of the encoder is a stream of pulses with
variable frequency according to the speed of the motor. The
optocouplers were used to isolate the high voltage circuits
from the low voltage controlling signals. The rating of the
motor should be chosen according to the rating of the
power circuit.
CONCLUSION
The DC machine is considered to be basic electric
machines. The aim of this paper is to introduce Technicians
to the modeling of power components and to use computer
simulation as a tool for conducting transient and control
studies. The Microcontroller based adjustable closed-loop
DC motor speed controller system has been developed. .
The results showed that the microcontroller is a reliable
instrument to control the motor. This system is applicable
to different sizes of motors and capable of controlling the
speed of the motors with very high precision.