MODELING AND DESIGN AN EMBEDDED CONTROLLER FOR A CONDENSER SYSTEM
ZULMAJD HAMDAN
“I hereby declared that I have read through this report and found that it has comply the partial fulfillment for awarding the degree of Bachelor of Electrical Engineering
(Control, Instrumentation, and Automation)”
Signature : ………..
Supervisor’s Name : Pn. Sahazati Binti Md. Rozali
MODELING AND DESIGN AN EMBEDDED CONTROLLER FOR A CONDENSER SYSTEM
ZULMAJD HAMDAN
This Report Is Submitted In Partial Fulfillment of Requirements for the Degree of Bachelor in Electrical Engineering (Control, Automation and Instrumentation)
Faculty of Electrical Engineering Universiti Teknikal Malaysia Melaka
“I hereby declared that this report is a result of my own work except for the excerpts that have been cited clearly in the references.”
Signature :………
Name : ZULMAJD HAMDAN IC No : 850423-04-5659
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ACKNOWLEDGEMENT
Praise to Allah S.W.T, The Almighty that give me the strength to finish and complete this project on time. First of all, I would like to thank my parent who help, motivate, and support me in order to complete this project.
Especially honor, I would like to thank Pn Sahazati as my supervisor for this PSM.
Besides, to Mohd Faizal Muhammadon, Muhammad Firdaus Abdul Rahim, Mohd Hafifi Muhammad Hanafiah, Sahrir Alias, Mr Yu Kee Thung and Mr Chye Ching Hock who teach me a lot about a car air-conditioner system. They give me full cooperation to complete this project.
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ABSTRACT
ABSTRAK
Tujuan utama projek ini adalah untuk mereka dan menyertakan pengawal untuk sistem pemeluap penyaman udara kereta. Terdapat empat komponen utama dalam sistem penyaman udara kereta iaitu injap pengembangan, pemampat, pemeluap dan penyejat. Pemeluap merupakan sejenis alat yang digunakan untuk menukarkan udara bertekanan tinggi menjadi air yang bertekanan tinggi. Udara bertekanan tinggi ini datang daripada pemampat. Pemeluap mempunyai tiub selari dan sirip penyejuk yang kecil. Sirip ini membantu udara melalui pemeluap dan menghilangkan kepanasan pada udara bertekanan tinggi tersebut seterusnya menukarkannya menjadi cecair. Tujuan utama projek ini ialah untuk mereka pengawal untuk sistem pemeluap ini.
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5.2 SOFTWARE PARTS 31
5.2.1 C-LANGUAGE PROGRAMMING 31
5.2.2 UPLOADING PROGRAM INTO PIC 32 5.3 THE OPERATION OF EMBEDDED CONTROLLER DESIGN
FOR CONDENSER SYSTEM 33
5.4 PROJECT RESULT 36
6.0 DISCUSSION 39
6.1 DICUSSION ON PROJECT OBJECTIVES AND PROJECT
SCOPES 39
6.2 DISCUSSION ON THE METHODOLOGY AND WORK
SCHEDULE 40
6.3 THE ADVANTAGES OF THE NEW INVENTIION 40 6.4 FUTURES SUGGESTION AND ENHANCEMENT 41
7.0 CONCLUSION 42
7.1 CONCLUSION 42
REFERENCES 44
FIGURE TITLE PAGE
2.1 PIC16F877A CONFIGURATION PINS 6
2.2 BASIC PIC CIRCUIT 7
2.3 CAR AIR-CONDITIONER PROCESS 11
2.4 COMPRESSOR 13
2.5 CONDENSER 14
2.6 EVAPORATOR 15
2.7 THERMAL EXPANSION VALVE 16
3.1 PIC16F877A 18
3.2 RS 232 SERIAL CABLE 19
4.1 METHODOLOGY FLOW CHART 22
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LIST OF TABLE
TABLE TITLE PAGE
2.1 C DATA TYPE 10
2.2 PASCAL EQUIVALENT 10
CHAPTER 1
INTRODUCTION
This chapter discuss about the introduction, project objectives, project scopes, and problem statement of this project.
1.1Introduction of the project
This project is built for a condenser in a car air-conditioning system. This condenser is controlled by a PIC with an appropriate programming using C Language. This project covered electrical, mechanical, and electronic engineering field.
By using a pressure switch, the condenser that connected to a PIC circuit will detect the pressured gas from a compressor. It will trigger the pressure sensor and the PIC circuit will send a signal to the condenser’s fan to switch it ON.
Condenser is a device designed to condense a gas into a liquid. It also designed to change the high pressure refrigerant vapor to liquid. The high pressure vapor is coming from the compressor. The condenser looks like a radiator, so it has parallel tubing and tiny cooling fin. The fins help the air flowing through the condenser, removing the heat and change the heat into much cooler liquid. The function of the cooling fan is to suck the outside air and flow through the condenser. So it is easier to cool the compressed air.
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1.2Project Objectives
To learn the basic concept of an air conditioner system.
To model and design a condenser system.
To design a controller for a condenser system.
To produce a complete system by combining both hardware and software part of the project.
1.3Project Scopes
To learn the basic process of condenser in a car air-conditioner system.
To learn the concept of microcontroller (PIC) PIC16F877A and micro-C programming to get finest tune.
To learn the best way of programming the micro-controller using C language.
To determine the suitable sensor to control a condenser (pressure sensor/switch).
Usually the old version of the condenser in the car used heat detector and timer to operate the cooling fan. Even though the air-conditioner did not switch on, the cooling fan still operates because the heat detector sense heat. So time spent of the battery did not last long.
The original system used a timer and heat detector to switch on the condenser’s
fan.
The cooling fan still operates even though there is no pressure.
1.5Problem Solving
The new version of the condenser is used only PIC controller and pressure switch in order to generate the whole condenser system. The cooling fan will only operate when the pressure switch sense pressure.
Used only a pressure sensor/switch to turn on the cooling fan.
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CHAPTER 2
LITERATURE REVIEW
This chapter discuss about the theory, the components, and the study that used in this project.
2.1 Introduction
The basic components used in this project will be, PIC circuit using PIC16F877A, condenser, pressure switch, and C Language.
To develop the controller for the system, the researches need to be done on the microchip. For example the datasheet, the rating, and all about it. For the condenser as well, some research had to be done.
2.2 Peripheral Interface Circuit (PIC)
full-microcontroller and its program are very tightly integrated. Microcontroller is wide used because of its need, from a sensor it will go to a microcontroller and it will trigger the actuators.
There are many ways to programming the PIC. It can use assembler (MPLAB), basic programming (PIC Basic Pro, Micro Basic), and C Language (HITEC PICC, MicroC). This project using C Language as its programming language. It is because the C Language is wide used. Almost everybody use C Language because of its uncomplicated.
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Figure 2.1: PIC16F877A configuration pins
Figure 2.2: Basic PIC circuit
Figure 2.2: Basic PIC Circuit
2.3 PIC (Peripheral Interface Circuit) Programming Language
The project use C-Language coding to program the PIC chip. The C-Language is the language that commonly used among programmer because it is easier create compared to other language.
2.3.1 The basics of C
We start with brief history of C before going through the C’s basic syntax and structure. Then we look at the characteristics of the C Language.
8 2.3.2 Characteristics of C
This subtopic will briefly list some of C's characteristics that define the language and also have lead to its popularity as a programming language. Naturally we will be studying many of these aspects throughout the course.
Although it is in small size, it can use much extensive use of function calls. Unlike PASCALS, the C Language is loose typing. The language also very discipline and structured. It also has a low level (BitWise) programming readily available. It also has the pointer implementation where the pointer is extensive use of pointers for memory, array, structures, and functions.
C now has become widely used because of its several characteristics. The C language has high-level constructs. It also can handle low-level activities. It can produce efficient program. The last reason why it is widely used is because it can be compiled on a variety of computers.
2.3.3 I/O Ports and Peripherals
of explicitly configuring things, just so that it is clear. Code runs fast, and extra start-up code is not likely to cause even a noticeable delay. Also, PICs have lots of program memory so we are not likely to run out of code space.
The best way to ensure that we use each I/O line properly is to look at the table for each I/O port which lists the pin function of each I/O line. We need to make sure that the pins can do what we want them to do, and then make sure that other peripherals which use each pin are configured to not interfere with our intended use of the pin. For instance, on the PIC16F627A the capture and compare module needs to be specifically disabled for PORTA to work normally. Also, some of the pins on PORTA are open
Function prototypes -- declare function types and variables passed to function.
Variables
Functions
Its must have a main () function.
2.3.5 Variables
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Figure 2.3: Car air-conditioner process
