SUDAN UNIVERSITY OF SCIENCE &TECHNOLOGY COLLEGE OF GRADUATE STUDIES MSc MECHATRONICS ENGINEERING GENERATING ENERGY FROM LOW ENVIROMENTAL VIBERATION BY USING ELECTROSTATIC ENERGY HARVESTER توليد الطاقة من اﻹهتزازات البيئية املنخفضة بإستخدام حاصـدة الطاقـة اﻹلكرتوستاتيكية A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN MECHATRONICS ENGINEERING PREPARED BY: MOHAMMED RASHID MOHAMMED ELZOUBIER SUPERVISED BY: Dr. MUSSAB ZARROG NOV 2015 ACKNOWLEDGMENT First of all, I would like to thank Allah, The Almighty Allah, for giving me the strength courage to endlessly pursue what is so called knowledge. I would like to express my sincere gratitude and deepest appreciation to my supervisor Dr. Mousab Zarrog, for his support, kind assistance, important advices and encouragement during all stages of the research. Also I would like to express my special thanks and extremely grateful to my family beginning from my father Mr. Rashid Mohammed and my mother Mrs. Siham Awad who supported me throughout this research and my brother Mr. Mojahid and My sisters Miss. Asia Miss. Amal for their courage to finish this research and their deepest love. I also wish to thank my dear friends Eng. Nadir Ahmed Ali and Eng. Mouid Elfatih for their help through the research and listening to my complaints, and my extremely grateful to all of those friends who had supplied me with unlimited encouragement and friendship throughout my period of study I ABSTRACT This research focuses on vibration energy harvesting using electrostatic converters. It synthesizes the various works carried out on electrostatic devices, from concepts, models and up to prototypes; Integration of structures and functions has permitted to reduce electric consumptions of sensors, actuators and electronic devices. Therefore, it is now possible to imagine low-consumption devices able to harvest energy in their surrounding environment. One way to proceed is to develop converters able to turn mechanical energy, such as vibrations, into electricity: this research focuses on electrostatic converters using electrets. It develops an accurate analytical model of a simple but efficient cantilever-based electret energy harvester. Therefore, it proves that with vibrations of resonant frequency it is theoretically possible to harvest energy in μW per gram of mobile mass. This power corresponds to the maximum output power of a resonant energy harvester according to the model of William and Yates. The Simulations results are validated by model of William and Yates and other devices, the work includes Design, modeling and simulation by SOILDWORK, ANASYS and MATLAB of electro-mechanical and electrical properties of the structure, description of its behavior in operating model and phases of activity. Simulation results were compared with measured values of the produced prototype chip by other studies. These results can suggest possible modifications to the proposed structure for further optimization and application environment adaptation. II الملخص: ٘زا اٌبسث يشوض عٍٝ زصبد طبلت اﻻ٘خضاص ببسخخذاَ اٌّسٛﻻث اﻻٌىخشٚسخبحيىيٗ. ٚيدّع ِخخٍف اﻷعّبي اٌخي أخشيج عٍٝ اﻷخٙضةاﻻٌىخشٚسخبحيىيٗ، ِٓ اٌّفب٘يُ ٚإٌّبرج ٚزخٝ إٌّبرج اٌّصغشة. ٚلذ أحبذ اٌذِح بيٓ اٌٙيبوً ٚاﻻداء في اٌسذ ِٓ اسخٙﻻن اٌىٙشببء في أخٙضة اﻻسخشعبس ٚأٔظّت اٌخشغيً ٚاﻷخٙضة اﻹٌىخشٚٔيت،أصبر ِٓ اٌّّىٓ اﻵْ أْ ٔخصٛس اﻷخٙضة راث اﻻسخٙﻻن إٌّخفض لبدسة عٍٝ زصذ اٌطبلت ِٓ اٌبيئت اٌّسيطت بٙب. ِٚٓ اٌطشق اٌّطٛسٖ ٌٍّضي لذِب في حطٛيش اٌّسٛﻻث اٌمبدسة عٍٝ حسٛيً اٌطبلت اٌّيىبٔيىيت، ِثً اﻻ٘خضاصاث، إٌٝ وٙشببء:ٌزٌه يشوض ٘زا اٌبسث عٍٝ ِسٛﻻث وٙشببء ببسخخذاَ اٌطبمبث اٌىٙشببئيٗ اٌّشسٚ .ٗٔٛيطٛس ّٛٔرج حسٍيٍي دليك ٌسبصذاث اٌطبلٗ اٌبسيطت ٚاٌفعبٌت بإسخخذاَ طبلت اﻹٌىخشيج اٌمبئُ عٍٝ اٌىببٌٛي. ٚببٌخبٌي، فإٔٗ يثبج أٔٗ ِع ا٘خضاصاث إٌبحدٗ عٓ حشدد اٌشٔيٓ أٔٗ ِٓ اٌّّىٓ ٔظشيب ٌسصبد اٌطبلت بٛزذٖ اٌّبيىشٚ ٚاط ٌىً خشاَ ِٓ اٌىخٍت. ٘زٖ اٌمذسة حخٛافك ِع لذسة اٌطبلت اﻻٔخبخيت اٌمصٜٛ ِٓ زصبداث اٌطبلت اٌشٔبٔت ٚفمب ٌّٕٛرج ٌٚيبَ ٚييخس. ٚلذ حُ اٌخسمك ِٓ صست ٔخبئح اٌّسبوبة عٓ طشيك اٌّمبسٔٗ ِع ّٛٔرج ٌٚيبَ ٚييخس ٚبعض اﻻخٙضٖ اٌسببمت، اْ اٌخصّيُ ٚإٌّزخت ٚاٌّسبوبة اٌىٙشببئيت اٌّيىبٔيىيت ٚاٌىٙشببئيت ٚخصبئص اٌٙيىً، ٚٚصف سٍٛوٙب في ّٛٔرج اٌخشغيً ِٚشازً إٌشبط ٌمذ حّج بإسخخذاَ ٚ .MATLABٚ ANASYS ، SOILDWORKحّج ِمبسٔت ٔخبئح اٌّسبوبة ِع اٌميُ اٌّمبست ِٓ اٌششيست إٌّبرج إٌّخدٗ ِٓ دساسبث أخشٜ. ٘زٖ إٌخبئح يّىٓ أْ حشيش اٌي اٌخعذيﻻث اٌّسخٍّت عٍٝ اٌٙيىً اٌّمخشذ ٌّضيذ ِٓ اٌخسسيٓ ٚاٌخىيف ِع بيئت اٌخطبيك. III TABLE OF CONTENTS Page ACKNOWLEDGMENTS.................................................................................….............I ABSTRACT........................................................................................…...........................II LIST OF FIGURES ………………………………………………………………….....VII LIST OF TABLES ……………………………………………………………....…….VIII LIST OF SYMBOLS AND ABBREVIATION………………………………………….IX CHAPTER ONE: INTRODUCTION 1.1GENERAL INTRODUCTION........................................................................................1 1.2 Problem Statement……………….………………………………………………...….2 1.3 Objectives........................................................................................................................3 1.4 Chapters Organization………………………………………………………………...3 CHAPTER TWO: LITERATURE REVIEW 2.1 APPLICATIONS OF WIRELESS SENSOR NETWORK ………………………........4 2.1.1 Environmental monitoring……………………………………………….…..4 2.1.2 Health ……………………………………………………………………......4 2.1.3 Safety, security and military Applications…………………………….……..5 2.2 APPROACH AND METHODOLOGY..........................................................................6 2.3 HARVESTING ENERGY FROM VIBRATION………………………………...…....7 2.3.1. Converters & Electrostatic devices –Overview...............................................7 2.4. ADVANTAGES & DRAWBACKS OF ELECTROSTATIC DEVICES …………....8 2.5. ELECTRET-FREE ELECTROSTATIC VIBRATION ENERGY HARVESTERS (EVEH) ………………………………………11 2.5.1. Devices…………………………………………………….…………….….12 2.6 ELECTRET-BASED ELECTROSTATIC CONVERTER .........................................13 2.6.1: Electrets...…………………………………………………..…………….. 14 2.6.2. Definition and electret types…………………………………………….…14 2.7. ELECTRET-BASED ELECTROSTATIC (VEH) DESIGN…................................…15 2.7.1 History.........................................................................................................................15 2.10 Summary…………………………………………………………………..................21 IV CHAPTERTHREE: DESIGN & MODELING 3.1Electret-based energy harvesters using cantilever.........................................................18 3.1.1 William and Yates‟ general model for vibration energy harvesters..........................18 3.2. Conversion principles..........................................................................................….....19 3.2.1. Electret-based electrostatic converters ………………………...……............….….20 3.2.1.1. Electrets ……………………………………………...……………............….... 20 3.3. Analytical model of the „Cantilever-based electret energy harvester...........................21 3.3.1. Model of the mechanical system...............................................................…............21 3.3.2. Modeling of the electrostatic system…………………………………….................23 3.4. Complete analytical model……………………………………………...............……25 3.5. Matlab & simulink........................................................................................................27 3.6. Design the model..........................................................................................................28 3.7. Motion simulation and analysis....................................................................................29 3.8 Power Management Control Circuits (PMCC) dedicated to electrostatic VEH (e VEH)…………………………………………………………………………….….. 32 3.8.1 Need for Power Management Control Circuit (PMCC).............................................33 3.8.2. PMCC for Electret-Based Electrostatic VEH…………………………...................33 3.8.2.1. Passive power converters ………………………………………..........................33 3.8.2.2 Active power converters………………………….................................................34 3.8.2.2.1Energy transfer on maximum voltage detection.............................................34 3.8.2.2.2. Energy transfer with a pre-storage capacitor................................................35 CHAPTER FOUR: SOLUTION 4.1. THEORY vs. SIMULATION data...........................................................….............37 4.2 output power................................................................................................................40 4.3. Comparison with other devices...................................................................................41 V 4.4. Limits ..........................................................................................................................42 CHAPTER FIVE CONCLUSIONS AND RECOMMENDATIONS 5.1 Conclusions………………………………………………………......………..............44 5.2 Recommendation for future work……………………………….......……...............…45 VI LIST OF FIGURES Figure No Figure Title Page Figure 2.1 Electricity generations during walking...............................................................5 Figure 2.2.Electrostatic vibration energy harvesters…………………………….………10 Figure2.3 Standard electrets for electret-based electrostatic converter…………...………11 Figure.2.4 Electret-based electrostatic conversion – Concept……….………………......12 Figure2.5Electret-based electrostatic conversion – Charge circulation……......................12 Figure 2.6 Boland's electret-based generator prototype…………………………….…...13