The document presents a temperature-based fan speed controller designed to adjust the speed of a fan according to ambient temperature using a microcontroller. It includes a literature review highlighting energy savings, a detailed methodology outlining components and operation, and discusses results, applications, advantages, and disadvantages of the system. The conclusion emphasizes successful implementation and recommends further enhancements such as monitoring additional parameters and remote data transmission.

1. TEMPERATURE BASED FAN SPEED CONTROLLER
Prepared by :
Supervisor :

2. CONTENTS
• Chapter 1: Introduction
• Chapter 2: Literature Review
• Chapter 3: Methodology
• Chapter 4: Result and Discussion
• Chapter 5: Conclusion and Recommendation

3. INTRODUCTION
CHAPTER ONE
The idea behind this project is to control the speed of fan
using microcontroller based on variation in temperature.
temperature controlled fan is an
alternative way to deal with the
speed of the motor.
Temperature control is a process in
which the temperature of an object is
measured and the passage of heat
energy into or out of the object is
adjusted to achieve a desired
temperature.
Fig:1.1. temperature
controlled fan

4. INTRODUCTION CHAPTER ONE
Objectives
Measure the room temperature
Display the current temperature in the LCD
Vary the speed of fan accordingly
Reducing the power consumption

5. Literature Review
According to Tito Smailagich, given the high
cost of electrical power, replacing a
conventional on/off temperature control with a
proportional controller can often save energy
and money.
Lawrence Berkeley National
Laboratory in their articles mentioned
that in the manufacturing sector, fans
use about 78.7 billion kilowatt-hours
of energy each year. This
consumption represents 15 percent of
the electricity used by motors.
CHAPTER TWO
Fig:1.1. temperature controlled
fan

6. Methodology
CHAPTER THREE
Block diagram
fig:3.1. temperature based fan speed controller

7. Block diagram
Thermistor High Gain
Amplifier
Bridge
Rectifier
Comparator
Triac Optocoupler
Increase in
temperature
AC supply
230 V, 50Hz
230 V
AC
Fig:3.1. TEMPERATURE BASED FAN SPEED CONTROLLER

8. Methodology
CHAPTER THREE
Flow Chart
Fig:3.1. Flow Chart of temperature based fan speed
controller

9. METHODOLOGY
CHAPTER THREE
PRINCIPLE OF OPERATION OF TEMPERATURE BASED FAN SPEED CONTROLLER
In this project we are using LM35 series analog
temperature sensor. This is a precision integrated
circuit, whose output voltage is linearly
proportional to the Celsius (Centigrade)
temperature.
It is rated to operate over a -55 degree to +
150 degree Celsius temperature range. It has
+10.0mV/Celsius linear scale factor. The
output of this sensor will be connected to
ATMEGA-32 Micro-controller ‘s PORT-A.
Fig:3.2. Operation of a Metal Detector

10. CIRCUIT DIAGRAM
METHODOLOGY
CHAPTER THREE
Fig:3.2. Circuit diagram of a temperature based fan speed
controller

11. CIRCUIT DIAGRAM
METHODOLOGY
CHAPTER THREE
Fig:3.2. Circuit diagram of a temperature based fan speed
controller

12. CHAPTER THREE
COMPONENTS
METHODOLOGY
1. LM35(TEMPERATURE SENSOR)
2. ATMEGA32 micro-controller unit
3. Brushless variable speed DC Motor [DR-6634-514]
4. N-MOSFET (BUK9575-100A)
5. Resistors (10k ohm, 1k ohm)
6. LM7805 Voltage regulator IC

13. MAJOR COMPONENTS
METHODOLOGY
CHAPTER THREE
Fig:3.2. ATMEGA32 micro-controller
unit
Fig:3.2. LM35(TEMPERATURE SENSOR)
2.
Fig:3.2. N-MOSFET (BUK9575-100A)

14. METHODOLOGY
CHAPTER THREE
Design and Construction

15. Result and discussion
CHAPTER FOUR
Results
 After designing, simulating, assembling, soldering
and testing the circuit, we came to the conclusion
that our circuit of the temperature based fan speed
controller is working satisfactorily.
 The construction hardware perfect.
 The total project work perfectly and has negligible
amount of unexpected functioning.

16. Result and discussion CHAPTER FOUR
APPLICATION
 Personal computers
 Exhaust fans in large hotels
 Washing machines
 CD and DVD players

17. Result and discussion CHAPTER FOUR
Advantages and disadvantages
Advantages-
(1) Since it is an automated system ,it is programmed effectively so
that no interruptions would stop its functionality.
(2)To monitor the environment, that is not comfortable or possible
to monitor for humans(especially for extended periods of time)
(3) Prevents waste of energy.
Disadvantages-
(1) It can only be maintained by technical person .
(2) Due to temperature variation, after sometimes it’s efficiency
may be decreased .

18. Conclusion and Recommendation CHAPTER FIVE
Conclusion
 The problem statement is implemented.
 Hardware part is halfway implemented.
 Through simulations and after running the code in IDE abstract is
verified
 As the technology is going on developing day by day, we prefer
things to be done automatically and in the same way our projects
reduces the work to mankind.

19. Conclusion and Recommendation CHAPTER FIVE
Recommendation
• We can monitor more parameters like humidity, light and at the same
time control them.
•We can send this data to a remote location using mobile or internet.
We can draw graphs of variations in these parameters using computer.
•When temperature exceeds the limit, a call will be dialed to the
respective given number by an automatic Dialer system.

20. Thank you 
Any Queries ? ? ?