This document presents a project on four quadrant speed control of a DC motor using a microcontroller. It describes the basic principles of four quadrant operation and components used including a transformer, rectifier, regulator, 8051 microcontroller, motor driver, and DC motor. The circuit diagram and working are explained where the microcontroller provides control signals to the motor driver to run the motor forward, backward, or apply brakes. Potential applications include industrial automation and robotics. Future work may include wireless control using transmitters and receivers.

1. Under the guidance of
MR. NITISH KUMAR YADAV
ASST. PROFESSOR
A
Project Presentation
On
FOUR QUADRANT DC MOTOR SPEED CONTROL WITH
MICROCONTROLLER
Submitted by
PRADEEP KUMAR (1573720904)
SANJAY KUMAR SAROJ (1573720906)
SUSHIL KUMAR (1573720909)
DEPARTMENT OF ELECTRICAL ENGINEERING

2. CONTENT
 Introduction
 Principle of four quadrant operation
 About dc motor
 Block diagram
 Components description
 Circuit diagram
 Working
 Advantages
 Applications
 Future work
 Reference

3. INTRODUCTION
 The aim of this project is four quadrant speed and direction control of the DC
motor.
 The motor is operated in four quadrants as clockwise, counter clock-wise,
instantaneous forward brake and instantaneous reverse brake.
 The speed of DC motor is directly proportional to the DC voltage applied
across its terminals. Hence, if we control the voltage applied across its
terminal, we actually can control its speed.
 Instantaneous brake happens as a result of applying a reverse voltage across the
running motor for a brief period.

4. PRINCIPLE OF FOUR QUADRANT OPRATION

5. ABOUT DC MOTOR
 A DC motor is an electric motor that runs on D.C. supply.
 The speed of DC motor is directly proportional to the DC voltage applied
across its terminals. Hence, if we control the voltage applied across its terminal,
we actually can control its speed.

6. BLOCK DIAGRAM

7. TRANSFORMER
 A transformer is an electrical device that transfers electrical
energy between two or more circuit through electromagnetic
induction.
 A varying current in one coil of the transformer produces a
varying magnetic field, which in turn induces a voltage in a
second coil.

8. BRIDGE RECTIFIER
 A Bridge rectifier is an Alternating Current (AC) to Direct
Current (DC) converter that rectifies mains AC input to DC
output.
 Bridge Rectifiers are widely used in power supplies that
provide necessary DC voltage for the electronic components or
devices.
 They can be constructed with four or more diodes or any other
controlled solid state switches.

9. VOLTAGE REGULATOR
 A voltage regulator is designed to automatically maintain a
constant voltage level.
 A voltage regulator may use a simple feed-forward design
or may include negative feedback.
 It may use an electromechanical mechanism, or electronic
components.

10. MICROCONTROLLER 8051
 This unit is the brain of the system. This is responsible for the
full control of the system.
 The microcontroller used here is a common 8 bit Atmel
microcontroller AT89s8253.It is a low-power, high-
performance CMOS 8-bit microcontroller with12K bytes of
In-System Programmable (ISP) Flash program memory and
2K bytes of EEPROM data memory. It has 32 programmable
input output lines.

11. Fig. Pin diagram of 8051 microcontroller

12. MOTOR DRIVER
 Used to drive the DC motors as directed by the
microcontroller. This is the OUTPUT block. Here we used
L293D to drive the motors .whatever signals it receives from
the microcontroller on the basis of that it will drive the motors.
 An H-bridge is an electronic circuit which enables a voltage to
be applied across a load in either direction. These circuits are
often used in robotics and other applications to allow DC
motors to run forwards and backwards. H-bridges are available
as integrated circuits, or can be built from discrete
components.

13. Fig. Pin diagram of L293D motor drive

14. MOTOR
 We will be using DC motor.
 A direct current (DC) motor is a
fairly simple electric motor that
uses electricity and a magnetic
field to produce torque, which turns
the motor.
 At its most simple, a DC motor
requires two magnets of opposite
polarity and an electric coil, which
acts as an electromagnet.
 The repellent and attractive
electromagnetic forces of the
magnets provide the torque that
causes the DC motor to turn.

15. CIRCUIT DIAGRAM
Fig. circuit diagram of four quadrant DC motor

16. WORKING
 The following procedures are carried out for the four quadrant
DC motor speed control operation using microcontroller.
 starts rotating in full speed being driven by a motor driver IC
L293D that receives control signal continuously from the
microcontroller.
 When clockwise switch is pressed the motor rotates in
forward direction as per the logic provided by the program
from the microcontroller to the motor driver IC.
 While forward brake is pressed a reverse voltage is applied to
the motor.
 switch is pressed the microcontroller delivers a logic to the
motor driver IC that develops for very small time a reverse
voltage.

17. ADVANTAGES
 Reduces the time of switching due to PWM.
 Requires least maintenance.
 It is user-friendly.
 Safer to use.

18. APPLICATIONS
 Hardware Automation.
 Robotic controlled applications.
 Can be used to control industrial rotors.
 DC vehicle control.

19. FUTURE WORK
 It can be provide wireless control by using transmitter after
microcontroller and a receiver to the motor drive.
 A complete automation can be provide by using suitable
sensors.

20. REFRENCES
1. https://www.goelectricdrive.org
2. Books on Microcontroller: 8051 microcontroller and
embedded systems.
3. Books on DC motors: BL.Theraja. “DC Motors and drives’’.
4. www.electricdrive.be
5. https://www.google.com/search?q=four+quadrant+dc+motor+
speed+control+with+microcontroller+ppt&sourceid=chrome
&ie=UTF-8