臺灣博碩士論文加值系統

許多研究成果中顯示，利用壓電材料之正電壓效應來發電是頗為適合的替代能源方式，其利用振動現象作為能量來源，透過壓電材料將這些振動能量轉換成有用的電能，為本研究之重點。本文亦探討利用壓電單晶片的發電效率，以及利用電源轉換器將機械能轉換成電能之效率，以及瞭解討論各種儲能電池原理及架構以及優缺點，並分析以壓電材料發電之儲能效益。
實驗是利用氣壓設備以固定之頻率施壓於單晶片式壓電材料元件使其變形產生電能。發電及儲能效率均有理論分析及實驗驗證，其結果頗為相似，亦測試在不同振動頻率之發電效果。例如以2.5Hz的操作頻率下施壓於壓電材料元件可產生33.84 mW的能量，其發電效率可達13.5%，而且可將1800mAh NiMH 1.2V電池在30分鐘充滿，達到電容峰值電壓100µF需150秒，470µF需330秒。

A great deal of research has repeatedly demonstrated that piezoelectric energy harvesters by using piezoelectric direct effect hold the promise of providing an alternative power source. Ambient vibrations have been the focus as a source due to the amount of energy available in them. How to harvest the vibration energy and transfer into useful electricity and store into a battery is the primary investigation in this article. Also, efficiency of energy harvesting of a piezoelectric unimorph and mechanical to electrical conversion of a converter is studied. An overview of power storage devices explores the background of rechargeable batteries and capacitors, the advantages and disadvantages of each. Also the effectiveness of piezoelectric energy harvesting for the purpose of battery charging is explored, with particular focus on the current output of piezoelectric harvesters.
Pneumatic equipment with fixed frequency is continuously press the piezoelectric unimorph to cause deformation, from which the electricity is generated. Analytical and experimental computation for the efficiency of electromechanical conversion and storage are carried out and shows a good agreement. Also, different vibration frequencies are tested. For an example of 2.5Hz, it can generate 33.84mW and obtain 13.5% electromechanical conversion efficiency, and fully charge a battery of 1800mAh NiMH 1.2V within 30 minutes for 150 and 330 seconds to achieve peak voltage of a 100µF and a 470µF capacitor respectively.

Table of Contents

Chinese Abstract I
English Abstract II
Acknowledgements III
Table of Contents IV
List of Figures VI
List of Tables VIII
Nomenclature IX
Chapter 1 Introduction 1
1.1 Problem statement 1
1.2 Literature review 2
1.3 Objective 7
1.4 Research contribution 7
1.5 Chapter summary 8

Chapter 2 Theory of Piezoelectric Unimorph 10
2.1 Introduction of piezoelectric 10
2.2 Piezoelectric unimorph 13
2.3 Equivalent circuit of piezoelectric unimorph 16
2.4 Analytical power estimation and electromechanical efficiency 19

Chapter 3 Introduction to Buck Converter 23
3.1 Principle work of buck converter 23
3.2 Transition between continuous and discontinuous 25
3.3 Voltage ratio of buck converter (discontinuous mode) 26
3.4 Piezoelectric energy harvest using buck converter 27

Chapter 4 Power Storage 28
4.1 Battery technology for energy storage 28
4.1.1 Basic battery theory 28
4.1.2 Rechargeable Nickel Metal Hydride 28
4.1.3 Rechargeable Lithium-based 29
4.1.4 Rechargeable thin film lithium ion 30
4.2 Current capacitor technology for energy storage 30
4.2.1 Electrolytic capacitors 30
4.2.2 Supercapacitors 31
4.3 Comparison of Energy Storage Methods 33
Chapter 5 Design and Experiment of Piezoelectric Unimorph 35
5.1 Design approach 37
5.2 Analytical simulation power efficiency 39
5.2.1 Power output of piezoelectric unimorph 39
5.2.2 Piezoelectric unimorph vibration harvested 41
5.2.3 Resistive load 43
5.3 Experimental and results 44
5.3.1 Piezoelectric 44
5.3.2 Capacitor 50
5.3.3 Battery 53
5.4 Piezoelectric energy harvest using buck converter 58
5.5 Discussion 62

Chapter 6 Conclusion and Future Study 66
6.1 Conclusion 66
6.3 Future study 67

References………………………………………………………………………. 68
List of Figures

2.1 The modal axes with respect to polling vector p 11
2.2 Relationships for transverse compression/tension generator 12
2.3 Piezoelectric Unimorph lay-up 14
2.4 PZT unimorph TH-7R 15
2.5 No load output characteristics of a PZT unimorph 16
2.6 31-mode excitation in unimorph structure 17
2.7 Equivalent circuit model for a piezoelectric source 19
2.8 Electric power using different frequency 21
2.9 Twin cylinder pneumatic size 21

3.1 Buck converter 24
3.2 Voltage and current change 24
3.3 Buck converter at boundary 25
3.4 Buck converter – discontinuous conduction 26
3.5 Piezoelectric energy harvest using buck converter 27

4.1 Schematic of realistic capacitor model incorporating ESR 32
4.2 Plot of voltage of each capacitor with no load (overlapped) 32
4.3 Discharge curves of two capacitors and a battery across an 80 ohm
resistor 34

5.1 Diagram of the experimental setup 38
5.2 Piezoelectric unimorph voltage output 39
5.3 Model of a piezoelectric generator 44
5.4 Additional capacitor to produce an almost-DC voltage output 45
5.5 Power versus load for capacitor 470µF 48
5.6 Power versus load for capacitor 100µF 49
5.7 Power versus load for different capacitor; Frequency 2.5 Hz 49
5.8 Overall experiment equipment 50
5.9 Discharge of 470µF and 100µF capacitor 51
5.10 Charge curve for 470µF capacitor from piezoelectric unimorph 51
5.11 Charge curve for 100µF capacitor from piezoelectric unimorph 52
5.12 Charge curve for 100µF and 470µF capacitors from piezoelectric
unimorph 52
5.13 Discharge curve of 1800 mAh NiMH across 220 ohm resistor 53
5.14 Discharge curve of 1200 mAh Li-ion across 220 ohm resistor 54
5.15 Charge curve 1800 mAh NiMH 1.2V ; frequency 2.5 Hz 55
5.16 Charge curve 1800 mAh NiMH 1.2V ; frequency 1.25 Hz 55
5.17 Charge curve 1800 mAh NiMH 1.2V ; frequency 1.67 Hz 56
5.18 Charge curve for 1800 mAh NiMH 1.2 V with different pressing
frequency 56
5.19 Charge curve for 1200 mAh Li-ion 3.7V ; frequency 2.5 Hz 57
5.20 Power vs duty cycle for NiMH battery 60
5.21 Power vs duty cycle for Lithium ion battery 61
5.22 Power and efficiency vs duty cycle 61

List of Tables

2.1 Piezoelectric unimorph specifications 15
2.2 Electrical power with different stepping frequency 20

5.1 Recent energy harvesting project and associated power
electronics efficiency 36
5.2 Summary of piezoelectric generators 37
5.3 Comparison NiMH and Lithium ion Battery 38
5.4 Parameter data 39
5.5 Parameter and value material properties 42
5.6 Equipment data 44
5.7 Resistor load value 45
5.8 Resistor load 5.2 M-ohm; capacitor 470µF 46
5.9 Resistor load 10.4 M-ohm; capacitor 470µF 46
5.10 Resistor load 15.6 M-ohm; capacitor 470µF 46
5.11 Resistor load 20.8 M-ohm; capacitor 470µF 46
5.12 Resistor load 26 M-ohm; capacitor 470µF 46
5.13 Resistor load 31.2 M-ohm; capacitor 470µF 47
5.14 Resistor load 5.2 M-ohm; capacitor 100µF 47
5.15 Resistor load 10.4 M-ohm; capacitor 100µF 47
5.16 Resistor load 15.6 M-ohm; capacitor 100µF 47
5.17 Resistor load 20.8 M-ohm; capacitor 100µF 47
5.18 Resistor load 26 M-ohm; capacitor 100µF 48
5.19 Resistor load 31.2 M-ohm; capacitor 100µF 48
5.20 Summary of discharge characteristics 54
5.21 Voltage result from experiment 58
5.22 Parameter data for buck converter 58
5.23 Duty cycle, Vout, Iout and Pout for Li-ion battery 59
5.24 Duty cycle, Vout, Iout and Pout for NiMH battery 60
5.25 Summary of charged capacitor; NiMH; Lithium 63
5.26 Comparison power output and efficiency with previous researched 65
5.27 Comparison charged time with previous researched 65

[1] Umeda, M., Nakamura, K., and Ueha, S. “Energy Storage Characteristics of a Piezogenerator Using Impact Vibration” Japan Journal of Applied Physics, Vol. 36, Part 1, No. 5b, May 1997, pp.3146-3151.
[2]Umeda, M., Nakamura, K., Ueha, S. “Analysis of the Transformation of Mechanical Impact Energy to Electric Energy Using Piezoelectric Vibrator” Japan Journal of Applied Physics, Vol. 35, Part 1, No. 5b, May 1996, pp.3267-3273.
[3]Amirtharajah, R. and Chandrakasan, A. “Self-powered Low Power Signal Processing” Symposium on VLSI circuits digest of technical papers, 1997, pp.25-26.
[4]Sodano, H., Magliula, E. A., Park, G., and Inman, D. J. “Electric Power Generation using Piezoelectric Devices” 13th International Conference on Adaptive Structure and Technologies, 2002.
[5]Kymissis, J., Kendall, C., Paradiso, J., Gershenfeld, N. “Parasitic Power Harvesting in shoes” Presented at the second IEEE International conference on wearable computing. Draft 2.0, August 1999.
[6]Elvin, N. G., Elvin, A. A., and Spector, Myron. “A Self-powered Mechanical Strain Energy Sensor” Smart Materials and Structures, Vol. 10, 2001, pp.293-299.
[7]Ottman, G. K., Hofmann, H., Bhatt, A. C., and Lesieutre, G. A. “Adaptive Piezoelectric Energy Harvesting Circuit for Wireless, Remote Power Supply” IEEE Transactions on Power Electronics, Vol. 17, No. 5, September 2002, pp.1-8.
[8]Hofmann, H., Ottman, G. K., and Lesieutre, G. A. “Optimized Piezoelectric Energy Harvesting Circuit Using Step-Down Converter in Discontinuous Conduction Mode” 33rd Annual IEEE Power Electronics Specialists Conference, Cairns Convention Centre, Queensland, Australia. June 2002, pp. 1-14.
[9]Hausler, E. and Stein, L. “Implantable Physiological Power Supply with PVDF Film” Ferroelectronics, Vol. 60, 1984, pp. 277-282.
[10]Starner, T. “Human-powered Wearable Computing” IBM Systems Journal, Vol. 35, Nos. 3 & 4, 1996, pp.618-629.
[11]Allen, J. and Smits, A. “Energy Harvesting Eel” Journal of Fluids and Structures, Vol.15, 2001, pp.1-13.
[12]Lakic. “Inflatable Boot Liner with Electrical Generator and Heater” Patent No. 4845338, 1989.
[13]Amirtharajah, R., Chandrakasan, A. P. “Self-powered Signal Processing Using Vibration-based Power Generation” IEEE journal of solid-state circuits, Vol. 33, No. 5, May 1998, pp. 687-695.
[14]“Piezoceramic Tutorial” URL: http://www.piezo.com/appdata.html, Piezo Systems, Inc., Cambridge, Massachusetts, 1999.
[15]Dausch, D. and Wise, S. “Compositional Effects on Electromechanical Degradation of RAINBOW Actuators” NASA Langley Technical Report: NASA-98-tm206282, 1998.
[16]“THUNDER™ Product Data” Face International Corporation, 1997.
[17]Gray, Dwight E., ed., et al. “American Institute of Physics Handbook, 3rd Edition” McGraw Hill, 1972, pp 2.68-69.
[18]Feynman, R. P., Leighton, R. B. and Sands, M. “Elasticity” The Feynman Lectures on Physics, vol. II, Addison-Wesley Publishing Company, Reading, Massachusetts, 1965, pp. 38- 8-11.
[19]“Piezo Film Sensors Technical Manual” Amp, Incorporated, 1993.
[20]Toda, M. “Theory of OPT Rotary Generator” AMP Sensors, Inc., 1997, p. 1.
[21]Berlincourt, D. “Piezoelectric Crystals and Ceramics” Ultrasonic Transducer Materials, ed. O.E. Mattiat, Plenum Press, New York, New York, 1971.
[22]B. K. Bose (Editor) “Modern Power Electronics” IEEE Press, Piscataway, NJ, 1992, pp. ix-x.
[23]A. Q. Huang, N. X. Sun, B. Zhang, X. Zhou and F. C. Lee "Low voltage power devices for future VRM" IEEE ISPSD'98, pp. 395-398.
[24]Y. Xiao, et al. “Flip-chip flex-circuit packaging for power electronics” IEEE ISPSD’01, pp. 55-58.
[25]Terry Ericsen “New power switch packaging technologies” PCIM, May 1999, pp. 28-30.
[26]Fisher R., et al. “High frequency, low cost, power packaging using thin film power overlay technology“ IEEE APEC’95, pp. 12-17.
[27]“Energy storage” URL: http://en.wikipedia.org/wiki/Energy_storage, Wikimedia Foundation, Inc., U.S. registered, 2008.
[28]Cope, R. C. and Podrazhansky, Y. “The art of battery charging” IEEE, Fourteenth Annual Battery Conference on Applications and Advances, January 12-15, 1999, pp. 233-235.
[29]Linden, D. and Reddy, T. B. “Handbook of batteries” McGraw-Hill Professional: New York, 2002.
[30]Davi, S. “Basic of Design: Battery Power Management” Supplement to Electronic Design, June 7, 2004.
[31]Nazri, G. and Pistoia, G. “Lithium Batteries: Science and Technology” Kluwer Academic Publisher: Boston, 2004.
[32]Kiehne, H. A. “Battery Technology Handbook” Marcel Dekker: New York, 2003.
[33]Dudney, N. J. and Jang, Y. I. “Analysis of thin-film lithium batteries with cathodes of 50 nm to 4 m thick LiCoO2“ J. Power Sources, 119-121, pp. 300-304, 2003.
[34]Dudney, N. J. “Solid-state thin-film rechargeable batteries“ Materials Science and Engineering B, 116 (2005), pp. 245-249.
[35]“Thin Energy” URL: http://www.infinitepowersolutions.com/, Infinite Power Solution, Inc.
[36]Deeley, P. M. “Electrolytic capacitors” Recorder Press: Plainfield, New Jersey, 1938.
[37]N. Mohan, T. M. Undeland, and W. P. Robbins “Power Electronics: Converters, Applications, and Design” Second Edition, John Wiley & Sons, Inc., 1995
[38]Sabate, J. A., Kustera, D. and Sridhar, S. “Cell-Phone Battery Charger Miniaturization” IEEE Journal 2000.
[39]S. Roundy, P. Wright, and J. Rabaey, “A Study of Low Level Vibrations as a Power Source for Wireless Sensor Nodes” Computer Communications, 23, 2003, pp.1131–1144.
[40]Shenck N S and Paradiso J A “Energy scavenging with shoe-mounted piezoelectrics” IEEE Micro. 21, 2001, pp. 30–42.
[41]Ramsay M J and Clark W W “Piezoelectric energy harvesting for bio MEMS applications” Proc. SPIE 4332, 2001, pp. 429–38.
[42]Glynne-Jones P, Beeby S P and White N M Towards a piezoelectric vibration powered microgenerator IEE Proc.—Sci. Meas. Technol. 148 68–72.
[43]Sodano H A, Park G and Inman D J “Estimation of electric charge output for piezoelectric energy harvesting” Strain 40, 2004, pp." 49–58.
[44]Bayrashev A, Robbins W P and Ziaie B “Low frequency wireless powering of microsystrems using piezoelectric-magnetostrictive laminate composites” Sensors Actuators A 114, 2004, pp. 244–9.
[45]Marzencki M, Basrour S, Charlot B, Grasso A, Colin M and Valbin L “Design and fabrication of piezoelectric micro power generators for autonomous Microsystems” Proc. Symp. on Design, Test, Integration and Packaging of MEMS/MOEMS DTIP05 (Montreux, Switzerland) , 2005, pp. 299–302.
[46]Jeon Y B, Sood R, Jeong J-h and Kim S G “MEMS power generator with transverse mode thin film PZT” Sensors Actuators A 122, 2005, pp. 16–22.
[47]Beeby S P, Tudor M J and White NM, “Energy Harvesting Vibration Sources for Mycrosystems Applications” Measurement Science and Technology 17, 2006 IOP Publishing Ltd., pp. 175-195.
[48]“Pneumatic equipment” URL: http://www.nationalvalve.com/fastek.htm, National valve, Inc.
[49]Qian, Jinrong, “How to charge Li-ion batteries for portable devices more efficiently” URL: http://www.powermanagementdesignline.com/howto/, 2008.
[50] Sodano, H A and Inman, D J, “Comparison of Piezoelectric Energy Harvesting Devices for Recharging Batteries” Journal of Intelligent Material Systems and Structures, 2005, pp 799-807.
[51]I. Damlund. “Analysis and Interpretation of AC-Measurements on Batteries Used to Asses State-of-Health and Capacity Condition” Eighteenth International Telecommunications Energy Conference (INTELEC’95), 1995, pp. 828-833
[52]Demian Jr. A E, Gallo C A, Tofoli F L, Vieira Jr. J B, Freitas L C, Farias V J and Coelho E A A. “A Novel Microprocessor-based Battery Charger Circuit with Power Factor Correction” IEEE, 2004, pp. 1407-1410.
[53]P. Smalser “Power transfer of piezoelectric generated energy” United States Patent , Patent number 5,703,474, Dec. 1997.
[54]Mossi K, Green C, Ounaies Z and Hughes E “Harvesting Energy Using a Thin Unimorph Prestressed Bender: Geometrical Effects” Journal of Intelligent Material Systems and Structures, Vol. 16, March 2005, pp. 249-261.
[55]Pereyma M “Overview of the Modern State of the Vibration Energy Harvesting Devices” MEMSTECH, Lviv-Polyana, Ukraine, May 2007, pp. 107-112.
[56]Sodano H A and Inman D J “A Review of Power Harvesting from Vibration using Piezoelectric Materials” The Shock and Vibration Digest, 36(3), 2004, pp. 197-205.
[57]William C B and Yates R B “Analysis of micro-electric generator for microsystems” Sensors Actuators A 52, 1996, pp. 8-11.
[58]Stephen N G “On energy harvesting from ambient vibration” Journal Sound Vibration 293, 2006, pp. 409-425.