Control System Design For Temperature Alert System.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

CONTROL SYSTEM DESIGN FOR TEMPERATURE ALERT

SYSTEM

This report submitted in accordance with requirement of the Universiti Teknikal Malaysia Melaka (UTeM) for the Bachelor Degree of Manufacturing Engineering

(Robotic and automation) with Honours

NOOR HISHAM BIN MOHAMAD SAID B050810184

FACULTY OF MANUFACTURING ENGINEERING 2011

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS LAPORAN PSM

TAJUK: Control System Design for Temperature Alert System SESI PENGAJIAN: 2010/11 Semester 2

Saya NOOR HISHAM BIN MOHAMAD SAID

mengaku membenarkan tesis (PSM/Sarjana/Doktor Falsafah) ini disimpan di Perpustakaan Universiti Teknikal Malaysia Melaka (UTeM) dengan syarat-syarat kegunaan seperti berikut:

1. Tesis adalah hak milik Universiti Teknikal Malaysia Melaka dan penulis.

2. Perpustakaan Universiti Teknikal Malaysia Melaka dibenarkan membuat salinan untuk tujuan pengajian sahaja dengan izin penulis.

3. Perpustakaan dibenarkan membuat salinan tesis ini sebagai bahan pertukaran antara institusi pengajian tinggi.

4. *Sila tandakan (√)

SULIT

TERHAD

TIDAK TERHAD

(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia yang termaktub di dalam AKTA RAHSIA RASMI 1972)

(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan)

(TANDATANGAN PENULIS) Alamat Tetap:

NO 15 JALAN DR 2, TAMAN DUYONG RIA 75460 MELAKA, MELAKA.

Tarikh: _______________________

Disahkan oleh:

(TANDATANGAN PENYELIA) Cop Rasmi:

Tarikh: _______________________

* Jika tesis ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasa/organisasi berkenaan dengan menyatakan sekali sebab dan tempoh tesis ini perlu dikelaskan sebagai SULIT atau TERHAD.

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DECLARATION

I hereby declare that this report entitled “Control System Design for Temperature Alert System” is the result of my own research except as cited in the references.

Signature :

Author’s Name : Noor Hisham bin Mohamad Said

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APPROVAL

This report is submitted to the Faculty of Manufacturing Engineering of UTeM as a partial fulfillment of the requirements for the degree in Bachelor of Manufacturing Engineering (Robotic and Automation). The members of the supervisory committee are as follow:

……… (Madam Nur Aidawaty Binti Rafan)

Main Supervisor

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ABSTRAK

Dalam sistem kejuruteraan suhu merupakan pembolehubah fizikal yang perlu dipantau dan dikawal. Sebagai contoh, sensor suhu digunakan di gedung-gedung, kilang pemprosesan kimia, mesin, komputer, kenderaan, dan lain-lain. Suhu yang amat tinggi boleh merosakkan kualiti dalam sesuatu sistem, sedangkan suhu rendah pula menyebabkan pembakaran dalam masa yang lama. Dengan meningkatkan kualiti sistem kawalan boleh mengawal suhu dengan mencapai bacaan yang memuaskan. Projek ini lebih tertumpu kepada sistem kawalan reka bentuk dengan menggunakan simulasi pada perisian MATLAB. Kaedah yang digunakan adalah berdasarkan rekaan pengawal PID, yang meningkatkan konsisten ralat dan tindak balas sementara secara bebas. Projek ini juga melibatkan analisis unsur-unsur sistem kawalan dengan membezakan nilai konsisten ralat dan tindak balas sementara (masa puncak, masa naik, masa penetapan) hasil daripada graf simulasi daripada input unit langkah untuk pampasan dan terpampas sistem. Satu daripada objektif reka bentuk sistem kawalan adalah proses penstabilan oleh itu, analisis sistem diteruskan dalam istilah kestabilan supaya mencapai objektif dengan mencari julat (K) supaya sistem itu akan beroperasi samada system stabil, tidak stabil atau hampir-hampir stabil supaya proses yang dilakukan akan beroperasi dalam keadaan yang sebaik mungkin

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ABSTRACT

In many engineering systems temperature constitutes an important physical variable that needs to be monitored and controlled. For example, temperature sensors are present in buildings, chemical processing plants, engines, computers, vehicles, etc. A very high temperature may destroy the qualities of the some system, while a low temperature may result in long burning time. By enhancing quality of control system can make the controlled temperature reach a satisfactory point. This project will focus primarily on the design control system by using simulation on MATLAB software. The method is based on the designing the PID controller, which improving the steady-state error and transient response independently. This project also involves analysis the elements of control system by differentiate the value of steady-state error and the transient response (peak time, rise time, settling time) from the simulation graft of unit step input for the uncompensated and compensated system. The one objective of control system design is process stabilization so that the analysis of the system will continue in term of stability to achieved the objective by finding the range of the gain (K) in the systems so that, the system will operate either stable, unstable or marginally stable in order to processes operates in the best possible way.

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DEDICATION

I dedicate this PSM thesis to my beloved parents, my lovely brothers and sisters, friends and colleagues, not forgot UTeM’s lecturers.

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ACKNOWLEDGEMENT

In the name of Allah, invocation and greetings to adoration of Nabi Muhammad (S.A.W.), thanks to God because giving me strength and patience in finishing this final year project and thesis writing on time. Alhamdulillah. Firstly I would like to express my appreciation to my supervisor Puan Nur Aidawaty Rafan for her guidance, advice and continuous encouragement in process of completing my project successfully. Besides that, a lot of cooperation to all staff and officer at Manufacturing Lab that help me had done my experiment. I would also want to express my thankfulness to my beloved parents for never ending support, advice and encouragement since childhood until now. May your love and support will never be gone until the end of my life. For UTeM’s lecturers who have taught me, thank you for giving me precious and valuable knowledge. For my friends and my classmates, thanks for your cooperation, support and help throughout these 3 years in UTeM. Thank you so much.

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TABLE OF CONTENT

Abstrak i

Abstract ii

Dedication iii

Acknowledgement iv

Table of Content v

List of Tables x

List of Figures xi

List of Abbreviation xv

1. INTRODUCTION

1.1 Background 1

1.2 Problem Statement 2

1.3 Project Objective 3

1.4 Project Scope 4

1.5 Project Planning 5

2. LITERATURE REVIEW

2.1 Introduction 7

2.2 Temperature Sensor 7

2.2.1 Selecting a Temperature Sensor 8

2.2.2 Thermocouple Temperature Sensor 8

2.3 Time Response 10

2.3.1 Natural Frequency 12

2.3.2 Damping Ratio 12

2.3.3 Underdamped Second-Order Systems 13

2.4 Stability System 16

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2.5.1 Application to Stable Systems 18

2.5.2 Evaluating Steady-State Error 18

2.5.3 Sources of Steady-State Error 19

2.6 Temperature Control 20

2.6.1 Ideal Integral Compensation (PI) 20

2.6.2 Ideal Derivative Compensation (PD) 21

2.6.3 Proportional Integral Derivative (PID) 22

2.7 Computer Aided Design 23

2.7.1 MATLAB Software 24

2.8 Temperature Control Application by means of a 25 PIC16F877 Microcontroller

2.8.1 Introduction 25

2.8.1.1 The Heat Control System 25

2.8.1.2 Input Layer 26

2.8.1.3 Output Layer 27

2.8.2 Control Methods 29

2.8.2.1 Stages of Digital PID Controller Design 29

2.8.2.2 Stages of Fuzzy Controller Design 30

2.8.3 Control Program 32

2.8.4 Experimental Results 33

2.8.4.1 Result of PID Control 33

2.8.4.2 Result of Fuzzy Control 34

2.8.5 Conclusion 35

3. METHODOLOGY

3.1 Introduction 36

3.2 Project flow planning 36

3.3 Literature Stage 46

3.4 Experiment: At Machining Process (Press Drill Machine) 38

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vii

3.6 Comparison and Analysis Stage 39

3.7 Tool and Equipments 39

3.7.1 Thermocouple type –K 40

3.7.2 Vernier Lab Pro 40

3.7.3 Logger Pro 3 41

3.7.4 Workpiece for Experiments 41

4. DESIGN AND DEVELOPMENT

4.1 Introduction 43

4.2 Conceptual Design 43

4.2.1 Software Design 44

4.2.2 Importing data 44

4.2.3 Building the Block Diagram 48

4.2.3.1Block diagram representation of control systems 49

4.2.3.2Control system operation 50

4.2.4 Designing PID Controller 51

4.2.4.1 MATLAB programming for design PID Controller 52

4.2.5 Static Error Constants 54

4.2.5.1System Type 55

4.2.5.2MATLAB Programming for Steady-state Error 56

4.2.6 Stability Design of the system 56

4.2.6.1Generating a Basic Routh Table 57

4.2.6.2MATLAB Programming for analysis the stability by using 59 RH Table

5. RESULT AND DISCUSSION

5.1 Introduction 60

5.2 Project Finding 60

5.3 Experimental for This Project 61

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viii

5.4.1 Transfer Function of the System (Aluminum) 62 5.4.2 Block Diagram of the System (Aluminum) 63 5.4.2.1MATLAB Command to find the Transfer Function 64

(Aluminum)

5.4.2.2Reduction of the Block Diagram (Aluminum) 64

5.4.3 Controller of the System (Aluminum) 65

5.4.4 Steady-state Error of the System (aluminium) 73 5.4.5 Characteristics between Uncompensated, PD and PID 76

(Aluminium)

5.4.6 System Stability of Aluminium 77

5.5 Experiment by using Mild Steel Material 82 5.5.1 Transfer Function of the System (Mild steel) 82 5.5.2 Block Diagram of the System (Mild steel) 83 5.5.3 Controller of the System (Mild steel) 83 5.5.4 Steady-state Error of the System (Mild steel) 86 5.5.5 Characteristics between Uncompensated, PD and PID 89

(Mild Steel)

5.5.6 Stability of the System of Mild Steel 90 5.6 Experiments to Measure Car Engine Block 92 5.6.1 Transfer Function of the System (Car Engine Block) 92 5.6.2 Block Diagram of the System (Car Engine Block) 93 5.6.3 Controller of the System (Car Engine Block) 93 5.6.4 Steady-state Error of the System (Car engine block) 96 5.6.5 Characteristics between Uncompensated, PD and PID 99

(Car engine block)

5.6.6 Stability of the System of Mild Steel 100

6. CONCLUSION AND RECOMMENDATION

6.1 Conclusion 102

6.1.1 Limitation 103

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REFERENCE 105

APPENDIX

A Data for Temperature Reading 107

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LIST OF TABLES

2.1 Temperature Sensors 8

2.2 Test waveforms for evaluating steady-state errors of position control systems 17 4.1 4.2 4.3 4.3

Correlation kp, ki and kd to the characteristic of the system

Relationships between input, system type, static error constants, and steady-state errors

Initial layout for Routh Table Completed Routh table

51 56 57 58 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10 5.11

Predicated characteristic for uncompensated, PD-, and PID-compensated system of Aluminum

Routh table for Aluminum

Routh table for Aluminum with K= -468.7 Routh table for Aluminum with K= -78.75 Summary of pole location for Aluminum

Predicated characteristic for uncompensated, PD-, and PID-compensated system of Mild Steel

Routh table for Mild steel with K= -78.75 Summary of pole location for Mild steel

Predicated characteristic for uncompensated, PD-, and PID-compensated system of CEB

Routh table for Car engine block with K= -67.5 Summary of pole location for Aluminum

76 78 79 79 80 89 90 91 99 100 101

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LIST OF FIGURES

1.1 1.2 1.3 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11 2.12 2.13 2.14 2.15 2.16 2.17 2.18 2.19 2.20 2.21 2.22

The General Control System Gantt chart for PSM 1

Gantt Chart for Overall Project PSM I and II

A thermocouple circuit

Comparison of thermocouple junction mounting Step response for second-order system damping case Second order system, pole plots and step response Second-order response as a function of damping ratio Second-order underdamped response specifications Steady-state error

PI Controller PD Controller PID Controller

Block Diagram of the Control System Heat Sensor and Measurement Amplifier Crystal and Voltage Supply Connections 2-2R Ladder Scheme

Pulse Width Modulator Triac Trigering Circuit Circuit of the LCD Driver

Block Diagram of a Closed Loop Digital Controller Membership Functions for E

Membership Functions for Offset Change of Heat

Membership Functions of the Variable That Adjusts the Fan’s Speed

Flowchart of the control program

2 5 6 9 9 10 11 13 14 19 21 22 23 25 26 26 27 27 28 29 30 31 31 32 32

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xii 2.23 2.24 2.25 3.1 3.2 3.2 3.4 3.5 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 4.12 4.13 4.14 5.1 5.2 5.3 5.4

Graph of System’s heating PID Control Result Fuzzy Control Result

Methodology flow chart Thermocouple Type K Vernier Lab Pro Vernier Logger Pro

Aluminium hollow box and mild steel bar

Current Window in MATLAB Import Wizard window in MATLAB Array Editor Window in MATLAB Plotting option in MATLAB Transfer function of plotting data Temperature Control system

Block Diagram representation of a Temperature Control System Programming for uncompensated system

Programming for PD-compensated system Programming for PID-compensated system Transfer function

Programming for Steady-state error Equivalent closed-loop transfer function Programming for stability system

Experiment at Press Drill machine

Graft Temperature VS Time for Aluminum Block diagram of the total system for Aluminum

MATLAB command of the total system for Aluminum (Transfer function) 33 34 35 37 40 40 41 42 45 46 47 47 48 49 51 52 53 53 55 56 57 59 61 62 63 64

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xiii 5.5 5.6 5.7 5.8 5.9 5.10 5.11 5.12 5.13 5.14 5.15 5.16 5.17 5.18 5.19 5.20 5.21 5.22 5.23 5.24 5.25 5.26 5.27 5.28 5.29

Transfer function of the total system for Aluminum Uncompensated feedback control system for Aluminum Root locus for uncompensated system of aluminum

Coding to find Root locus for uncompensated system of aluminum Zoom view of Root locus for uncompensated system of aluminum Calculating the PD compensator zero for aluminum

Root locus for PD-compensated system of aluminum

Coding to find Root locus for PD-compensated system of aluminum Root locus for PID-compensated system of aluminum

Coding to find Root locus for PID-compensated system of aluminum

Step responses for uncompensated, PD-, and PID-compensated system of Aluminium

Coding for steady-state error of uncompensated system (aluminum) Coding for steady-state error of PD-compensated system (aluminum)

Coding for steady-state error of PID-compensated system (aluminum)

Coding for analysis the stability by using RH Table (Aluminum) Pzmap for the stability system of Aluminum

Pzmap for the unstable system of Aluminum

Pzmap for the marginally stable system of Aluminum Graft Temperature VS Time for Mild steel

Uncompensated feedback control system for Mild steel Coding for Uncompensated system of Mild steel Coding for PD-compensated system of Mild steel

Coding for design PID-compensated system of Mild steel

Root locus and Step Response of Uncompensated, PD- and PID-uncompensated for Mild steel

Coding for steady-state error of uncompensated system (Mild steel)

64 65 66 66 67 68 69 69 70 71 72 73 74 75 77 80 81 81 82 83 83 84 84 85 86

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xiv 5.30 5.31 5.32 5.33 5.34 5.35 5.36 5.37 5.38 5.39 5.40 5.41 5.42 5.43 5.44

Coding for steady-state error of PD-compensated system (Mild steel)

Coding for steady-state error of PID-compensated system (Mild steel)

Coding for analysis the stability by using RH Table (Mild steel) Pzmap for the stable, unstable and marginally stable system of Mild steel

Graft Temperature VS Time for Car Engine Block

Uncompensated feedback control system for Car Engine Block Coding for Uncompensated system for Car engine block

Coding for design PD-compensated system for Car engine block Coding for design PID-compensated system for Car engine block Root locus and Step Response of Uncompensated, PD- and PID-uncompensated for Car engine block

Coding for steady-state error of uncompensated system (Car engine block)

Coding for steady-state error of PD-compensated system (Car engine block)

Coding for steady-state error of PID-compensated system (Car engine block)

Coding for analysis the stability by using RH Table (Car engine block)

Pzmap for the stable, unstable and marginally stable system of Car engine block 87 88 90 91 92 93 93 94 94 95 96 97 98 100 101

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LIST OF ABBREVIATIONS

PC - Personal Computer

RTD - Resistance Temperature Detector PID - Proportional Integrated Derivative PD - Proportional Derivative

PI - Proportional Integral DC - Direct Current AC - Alternative Current VB - Visual Basic

GUI - Graphical User Interface I/O - Input Output

CPU - Central Processing Unit CU - Control Unit

PWM - Pulse Width Modulator

IEEE - The Institute of Electrical and Electronic Engineers ADC - Analog Digital Computer

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CHAPTER 1

INTRODUCTION

1.1 Background

Temperature control is an important issue in many industrial processes, e.g., electric-resistance furnaces, crystal ovens, and heating boilers/tanks/barrels for various chemical and metallic products. Such a thermal process usually shows an integrating response characteristic during the heating stage, and after rising up to the set-point temperature, it tends to behave in a stable manner given a certain heating range, due to air convection or radiation loss into the environment. The main control challenges for such processes are to avoid overheating (i.e., temperature overshoot) in the heating stage and to tightly maintain the set-point temperature against load disturbances and process/environmental variations. Furthermore, thermal processes typically have slow time constants and long time delay, causing difficulties to control-system design. (Stanley M.Shinners, 1998)

The design procedure for designing a control system is an orderly sequence of steps. Good engineering design is interdisciplinary and requires that the engineer first thoroughly understand the customer’s requirements, the defined control system specifications, the environment that the control system will operate in, the available power, the schedule that it must be built in, and the available budget to do the job. Other considerations are reliability and maintainability which may dictate the kind of motor to use (i.e., electric motor or hydraulic motor). (Stanley M.Shinners, 1998)

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The general control system as shown in figure 1.1 can be divided into the controller and the machine. The controller can be divided into the control laws and the power converter. The machine may be temperature bath, a motor, or as in the case of a power supply, an inductor/capacitor circuit. The machine can also be divided in two: the plant and the feedback device(s). The plant receives two types of signals: a controller output from the power converter and the one or more disturbances. Simply put, the goal of the control system is to drive the plant in response to the command while overcoming disturbance. (George Ellis, 2000)

Figure 1.1: The General Control System (George Ellis, 2000)

1.2 Problem Statement

The most important parameter of some system is the temperature. For example, the Catalyst regeneration process regenerates the catalyst of a chemical reactor. An important variable, which is to be controlled, is the temperature of catalyst bed. A very high temperature may destroy the qualities of the catalyst, while a low temperature may result in long burning time. So, when the control system elements are introduced, the system become more stable by maintaining the temperature reaches a satisfactory point.

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Temperature is one of the most frequently used parameters in process measurements in industry. There are many controllers can be used and one of the controller is PID. Mostly heater using an on-off method of it was the simplest form on control. When the heater is hotter than the set point temperature the heater is switch off completely. Based on this method, the temperature is fluctuate and caused the temperature is not constant. So based on this problem PID method has been used. PID controller provides a close loop concept in system. This close loop system will ensure that there is no error at the output. It will fix the error in order to reach the set point value. Three terms in this controller will provide a good performance for the output. Each of this term has its own contribution for the system. When these three terms is combining, the system will perform more efficient and precise.

Once the system reached operating temperature, all we worried about was overheating. Computers used to control system performance through all stages of temperature, maintaining time constant and stability of system, sensitivity, accuracy and transient response. When using PID controller, user can be easily tuning according to the system requirement. Tuning is important in order to achieved good performance of the system. If problem occurred or the system requirement change, user can set the new tuning easy and faster.

1.3 Project Objective

i. Design the PID controller of Temperature Control System using the simulation in MATLAB software according to the system requirement. ii. Reduce the steady-state error of the system.

iii. Analysis the performance of designed control system such as the stability of the system by adjusting the gain, K either the system is stable, unstable or marginally stable.

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1.4 Project Scope

This project will focus primarily on the design control system, so that processes operate in the best possible way. Generally, complete control system may have controller and machine. The controller will be used for this project is PID system that improves the state error and transient response independently. Then differentiate the steady-state error for the uncompensated and compensated system for each process.

Once the PID controller are completely design, derive a proportional term, an integration term and a derivative term from the resulting transfer function of the PID compensator.

The improvements are focused on devising a new control technique that improves the system behavior against any kind of disturbances by study the performance which greatly improved the stability and control accuracy of the Temperature Alert System. The performance of a control generally specified in terms of stability, steady-state error and transient response.

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1.5 Project Planning

Semester Break Due Date Plan

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