DESIGN AND CONSTRUCTION OF MICROCONTROLLER BASED AMBIENT

Transcription

1 DESIGN AND CONSTRUCTION OF MICROCONTROLLER BASED AMBIENT TEMPERATURE COf~TROLLED FAN BY NNAM HELEf' AfVlUCHE 2005/22058EE A Project submitted to the Department Of Electrical and Computer Engineering. Federal University of Technology, Minna. November, 2010.

2 DEDICATION To God Almighty for sparing my life till this moment, to my family members for their encouragement and unending love, to all my friends, and all my colleagues for making it all possible for me to have completed this project. Ii

3 DECLARATION 1 Nnam Helen Amuche declare that this work was done by me and has never been presented elsewhere for the award of a degree. I also hereby relinquish the copy right to the Federal University of Technology, Minna. NNAM HELEN AMUCHE Student MR PAUL ATTAH Supervisor ~Joju/~ Signature and date ENGR RAJI H.O.D fli ~.\\ Qj:)\\l.~. ~ / / Signature and date Q~~.GJ(\ Extemal examiner Signature and date l(t~(o 111

4 ACKNO\VLEDGEMENT I thank God Almighty whose infinite grace led me throughout the project. Also thank Him for giving me the ability to overcome the ups and downs of running a successful degree program. I would like to appreciate the invaluable contribution of my honorable supervisor Mr: Paul Attah and the co assessor Mallam K. Mohammed for their supervision. I also appreciate the effort of my lovely parents Mr and Mrs Nnam for their constant help, prayers, financial and moral support, and their words of encouragement and advice. My lovely siblings, joy, Gloria, Sammy, Excel and Peace, I acknowledge your efforts on me. r also appreciate Mr. Obinna Emmanuel Okeke for his effort, support (morally and spiritually), prayers and all his advice. A well deserving appreciation goes to all my esteemed friends and colleagues; Folashade Tunmise Oyadiran, Mustapha Hafiz, Victoria Edu Ufaruna,Omite Ogbelu, Onyinye Uzochukwu, Grace Halima Baba, John Amakor, Osisiogu Enyinnaya, Rose Nwonye, Rakiya Zubairu, Divine Ekodi, Experience Jamiu, you are all appreciated. l V

5 ABSTRACT This project presents the design, construction and control of the speed of an electric fan based on the ambient temperature. This fan system consists of temperature.. sensor, analogue to digital converter, microcontrolier, liquid crystal display (LCD) with integration of software programming using A T89s52 as the microcontroller. The electric fan automatically switches the speed according to the ambient temperature changes using the temperature sensor LM35. lfthe temperature is between (18-25) c, it gives a logic high signal at the outputl.i.e. Relay l.if the temperature is between (26-32) c, it gives a logic high signal at the output 2.i.e.Relay 2. lfthe temperature is between (33-40) c, it gives a logic high signal at the output 3.i.e. Relay 3.ifthe temperature is below the lowest temperature and above the highest temperature, it gives a logic low signal at all outputs. This project also presents the expected performance of the automatic fan system, construction of hardware and software development to gather the performance data. v

6 TABLE OF CONTENTS Title page i Dedication Declaration A~kn ow 1 ed geiti ent Abstract Table of contents iii iv v VI Chapter One: Introduction 1.1 Project Background Problem statement : Aims and objectives S cope of work Methodology Reviews of thesis contents Chapter Two: Literature Review / Theoretical Background 2.1 Brief history of fan Methods of speed control PWMing the fan directly Linear regu lati on DC - DC regulation temperature and other parameters in process control available fan cooling system Temperature - based fan control using MAXQ2000 microcontroiier Digital I/O tern perature sensor VI

7 2.5 theoretical backgrounds Power supply ~ MicrocontroIIer Analog to digital converter : Temperature sensing unit The display unit Chapter Three: Design and Construction 3.1 Block diagram description The 89s52 microcontroiler Temperature sensor LM35 block Output block ADC 0804 block Display (LCD) block power supply block System software Components specification Construction Comprehensive circuit diagram Chapter four: Tests, results and discussion 4.1 Testing Temperature sensor (LM35) test ~ Analog to digital test Complete project test Vll

8 Chapter Five: Conclusions and Recommendation 5.1 Conc! usi ons Recomm endati on s References A ppen d ix A ppen d ix A P pen d ix Vlll

9 LIST OF FIGURES Fig 1.0. Workflow of the project Fig 2.1. Connection thermistor to the MAXQ2000 evaluation kit Fig 2.2. Connection of the PWM output to the fan Fi g 3.1. Block diagram of a tern perature controlled fan Fig 3.2. Temperature sensor LM Fig 3.3. ADC interfacing with microcontroller Fig x 2 LCD Fig 3.5 power supply of a rectifier ~ Fig 3.6 block diagram of a power supply Plate 3.7 veroboard construction Plate 3.8 the casing Fig 3.9 the circuit diagram of a microcontroller based ambient temperature controlled fan ix

10 LIST OF TABLES Table 3.0. Description of LCD pins Table 4.0. LM35 temperature sensor test ' x