Micro Energy Harvesting

With its inclusion of the fundamentals, systems and applications, this reference provides readers with the basics of micro energy conversion along with expert knowledge on system electronics and real-life microdevices. The authors address different aspects of energy harvesting at the micro scale with a focus on miniaturized and microfabricated devices. Along the way they provide an overview of the field by compiling knowledge on the design, materials development, device realization and aspects of system integration, covering emerging technologies, as well as applications in power management, energy storage, medicine and low-power system electronics. In addition, they survey the energy harvesting principles based on chemical, thermal, mechanical, as well as hybrid and nanotechnology approaches. In unparalleled detail this volume presents the complete picture -- and a peek into the future -- of micro-powered microsystems.

Autorentext
Danick Briand obtained his PhD degree in the field of micro-chemical systems from the Institute of Microtechnology (IMT), University of Neuchatel, Switzerland, in 2001. He is currently a team leader at EPFL IMT Samlab in the field of EnviroMEMS, Energy and Enviromental MEMS. He has been awarded the Eurosensors Fellowship in 2010. He has been author or co-author on more than 150 papers published in scientific journals and conference proceedings. He is a member of several scientific and technical conference committees in the field of sensors and MEMS, participating also in the organization of workshop and conferences. His research interests in the field of sensors and microsystems include environmental and energy MEMS.

Eric M. Yeatman has been a member of academic staff in Imperial College London since 1989, and Professor of Micro-Engineering since 2005. He is Deputy Head of the Department of Electrical and Electronic Engineering, and has published more than 160 papers and patents on optical devices and materials, and micro-electro-mechanical systems. In 2011 he was awarded the Royal Academy of Engineering Silver Medal. He has been principal or co-investigator on more than 20 research projects, and has acted as a design consultant for several international companies. His current research interests are in radio frequency and photonic MEMS devices, energy sources for wireless devices, and sensor networks.

Klappentext
Micro energy harvesting is the conversion of ambient energy, such as body warmth or machine vibration, into electric energy to locally power embedded, small-scale devices such as wireless personal health-monitoring systems or environmental sensors, making them independent of rapidly exhausted batteries or location restricted power grids. Enabling this unprecedented level of autonomy, particularly at the micro-scale, requires innovation in harvesting devices, power management circuits, and complete system design, in order to ensure the desired functionality and reliability of the respective device even if the supply of ambient energy varies with time.

This book addresses a wide range of aspects of energy harvesting at the micro-scale, with a focus on miniaturized and micro-fabricated devices. It provides an overview of the field by compiling knowledge on design, materials development, device realization and aspects of system integration. The book covers emerging technologies such as nanotechnology-based materials and harvesters, as well as applications in power management, energy storage, medical applications and low-power system electronics. In addition, it surveys the energy harvesting principles being developed at the micro-scale based on chemical, thermal, mechanical as well as hybrid and nanotechnology approaches.

Inhalt

About the Volume Editors XVII

List of Contributors XIX

1 Introduction to Micro Energy Harvesting 1
Danick Briand, Eric Yeatman, and Shad Roundy

1.1 Introduction to the Topic 1

1.2 Current Status and Trends 3

1.3 Book Content and Structure 4

2 Fundamentals of Mechanics and Dynamics 7
Helios Vocca and Luca Gammaitoni

2.1 Introduction 7

2.2 Strategies for Micro Vibration Energy Harvesting 8

2.2.1 Piezoelectric 9

2.2.2 Electromagnetic 10

2.2.3 Electrostatic 11

2.2.4 From Macro to Micro to Nano 11

2.3 Dynamical Models for Vibration Energy Harvesters 12

2.3.1 Stochastic Character of Ambient Vibrations 14

2.3.2 Linear Case 1: Piezoelectric Cantilever Generator 14

2.3.3 Linear Case 2: Electromagnetic Generator 15

2.3.4 Transfer Function 15

2.4 Beyond Linear Micro-Vibration Harvesting 16

2.4.1 Frequency Tuning 16

2.4.2 Multimodal Harvesting 17

2.4.3 Up-Conversion Techniques 17

2.5 Nonlinear Micro-Vibration Energy Harvesting 18

2.5.1 Bistable Oscillators: Cantilever 19

2.5.2 Bistable Oscillators: Buckled Beam 21

2.5.3 Monostable Oscillators 23

2.6 Conclusions 24

Acknowledgments 24

References 24

3 Electromechanical Transducers 27
Adrien Badel, Fabien Formosa, andMickaël Lallart

3.1 Introduction 27

3.2 Electromagnetic Transducers 27

3.2.1 Basic Principle 27

3.2.1.1 Induced Voltage 28

3.2.1.2 Self-Induction 28

3.2.1.3 Mechanical Aspect 29

3.2.2 Typical Architectures 30

3.2.2.1 Case Study 30

3.2.2.2 General Case 33

3.2.3 Energy Extraction Cycle 33

3.2.3.1 Resistive Cycle 34

3.2.3.2 Self-Inductance Cancelation 34

3.2.3.3 Cycle with Rectification 35

3.2.3.4 Active Cycle 36

3.2.4 Figures of Merit and Limitations 36

3.3 Piezoelectric Transducers 37

3.3.1 Basic Principles and Constitutive Equations 37

3.3.1.1 Physical Origin of Piezoelectricity in Ceramics and Crystals 37

3.3.1.2 Constitutive Equations 38

3.3.2 Typical Architectures for Energy Harvesting 39

3.3.2.1 Modeling 39

3.3.2.2 Application to Typical Configurations 40

3.3.3 Energy Extraction Cycles 41

3.3.3.1 Resistive Cycles 41

3.3.3.2 Cycles with Rectification 43

3.3.3.3 Active Cycles 43

3.3.3.4 Comparison 43

3.3.4 Maximal Power Density and Figure of Merit 44

3.4 Electrostatic Transducers 45

3.4.1 Basic Principles 45

3.4.1.1 Gauss's Law 45

3.4.1.2 Capacitance C0 45

3.4.1.3 Electric Potential 46

3.4.1.4 Energy 46

3.4.1.5 Force 47

3.4.2 Design Parameters for a Capacitor 47

3.4.2.1 Architecture 47

3.4.2.2 Dielectric 48

3.4.3 Energy Extraction Cycles 48

3.4.3.1 Charge-Constrained Cycle 49

3.4.3.2 Voltage-Constrained Cycle 50

3.4.3.3 Electret Cycle 51

3.4.4 Limits 51

3.4.4.1 Parasitic Capacitors 51

3.4.4.2 Breakdown Voltage 53

3.4.4.3 Pull-In Force 53

3.5 Other Electromechanical Transduction Principles 53

3.5.1 Electrostrictive Materials 53

3.5.1.1 Physical Origin and Constitutive Equations 53

3.5.1.2 Energy Harvesting Strategies 54

3.5.2 Magnetostrictive Materials 55

3.5.2.1 Physical Origin 55

3.5.2.2 Constitutive Equations 56

3.6 Effect of the Vibration Energy Harvester Mechanical Structure 56

3.7 Summary 58

References 59

4 Thermal Fundamentals 61
Mathieu Francoeur

4.1 Introduction 61 4.2 Fundamentals of Thermoelectric Power G...