Design of Miniaturized Variable-Capacitance Electrostatic Energy Harvesters

Preface
Contents
1 Kinetic Energy Harvesting Systems Overview
1.1 Energy Solutions
1.1.1 Battery
1.1.2 Energy Harvesting
1.1.3 Hybrid Solution
1.2 Overview of Energy Harvesting Systems
1.2.1 Energy Source
1.2.1.1 Environmental Sources
1.2.1.2 Power and Data Links
1.2.1.3 Kinetic Energy Sources
1.2.2 Transducer
1.2.2.1 Piezoelectric
1.2.2.2 Electromagnetic
1.2.2.3 Electrostatic
1.3 Electrostatic Harvester: An Example
1.4 Scope of This Book
1.4.1 Why Energy Harvesting
1.4.2 Why Kinetic Energy Source
1.4.3 Why Electrostatic Harvesters
1.4.3.1 Micro-scale Implementation Challenges
1.4.3.2 MEMS Compatibility
1.4.3.3 Frequency Dependency
1.4.3.4 Emerging Technologies
1.5 Structure
References
2 Electrostatic Harvesters Overview and Applications
2.1 Fundamentals of Electrostatic Harvesters
2.1.1 Operation of an Electrostatic Harvester
2.1.2 System-Level Structure of Electrostatic Harvesters
2.1.2.1 Non-Sustainable Electrostatic Harvesters
2.1.2.2 Sustainable Electrostatic Harvesters
2.1.3 Circuit-Level Electrostatic Harvester Example
2.1.4 QV Diagram
2.1.4.1 Switching Schemes
2.1.4.2 Possible Paths in QV Diagram
2.1.5 Categorizing Electrostatic Harvesters
2.1.5.1 QV Diagram-Based Categories
2.1.5.2 Circuit Feature Based Categories
2.1.5.3 The Relation Between These Naming Conventions
2.2 Generated Energy in a Variable Capacitor
2.2.1 C:C Example
2.2.2 C:V Example 1
2.2.3 C:V Example 2
2.3 Net Generated Energy and Conduction Losses
2.3.1 First Solution
2.3.1.1 Sustainable System
2.3.1.2 Non-Sustainable System
2.3.1.3 Overall
2.3.2 Second Solution
2.3.2.1 Sustainable System
2.3.2.2 Non-Sustainable System
2.3.2.3 Overall
2.3.3 Example
2.3.3.1 First Solution
2.3.3.2 Second Solution
2.4 Discrete Analysis of Electrostatic Harvesters
2.4.1 Discrete Analysis
2.4.2 Solving Linear Non-Homogeneous Recursive Expressions
2.4.3 Charge-Depletion Study
2.4.3.1 Case Study
2.4.3.2 Delivered Energy to the Load
2.4.3.3 The Net Generated Energy and the Conduction Losses
2.5 Conclusion
References
3 Switched-Capacitor Electrostatic Harvesters
3.1 Switched-Capacitor Charge Transfer
3.1.1 Using a Transistor
3.1.2 Current Expression
3.1.3 Switching Scenarios
3.1.3.1 The Switch Is on for Long Enough
3.1.3.2 The Switch Is Not on for Long Enough
3.1.4 Energy Transfer and Conduction Losses
3.1.5 Charge Conservation Law
3.1.6 Overall View
3.2 Study of Elementary Switched-Capacitor Harvesters
3.2.1 First Elementary Harvester
3.2.1.1 The Core Harvester
3.2.1.2 The Harvester with Load in Series
3.2.1.3 The Harvester with Load in Parallel
3.2.1.4 Overall
3.2.2 Second Elementary Harvester
3.2.2.1 The Core Harvester
3.2.2.2 Harvester in Practice
3.2.2.3 Overall
3.2.3 Charge-Depletion Issue
3.3 Study of Sustainable Switched-Capacitor Harvesters
3.3.1 The Core Harvester
3.3.1.1 Closed-Form Expressions
3.3.1.2 Simulation
3.3.1.3 The Voltage Dependencies
3.3.1.4 Investigating Charge-Depletion Issue
3.3.2 The Harvester with Load
3.3.2.1 Maximal Resistive Load
3.3.2.2 Energy Calculations
3.3.2.3 Efficiency Optimization
3.3.2.4 Voltage Control Mechanism
3.3.2.5 Start-Up and Fault Prevention Mechanism
3.3.3 The Harvester for Battery Charging
3.3.3.1 Closed-Form Expressions
3.3.3.2 Energy Calculations
3.3.3.3 Efficiency
3.4 Circuit Implementation
3.4.1 Discrete Transistors
3.4.2 Integrated Transistors
3.4.3 Control Circuit
3.5 Applications and Simulations
3.5.1 A Variable Capacitor
3.5.2 Energy Harvesting from Knee Joint
3.5.3 Energy Harvesting from Diaphragm Muscle
3.5.3.1 Diaphragm Muscle
3.5.3.2 Harvester and Simulations
3.5.4 Volume Estimation
References
4 Asynchronous Electrostatic Harvesters
4.1 Diode-Based Charge Transfer
4.1.1 Using a Diode
4.1.2 The Storage Is Not a Battery or a Large Capacitor
4.1.3 The Storage Is a Battery or a Large Capacitor
4.1.4 Energy Transfer and Conduction Losses
4.2 Non-sustainable Core Asynchronous Harvester
4.2.1 Operation and the Voltages Across the Capacitors
4.2.2 The Saturation Issue
4.2.3 Simulation and QV Diagram
4.3 Sustainable Asynchronous Harvester with Flyback Circuit
4.3.1 Operation of the Harvester
4.3.2 Calculation of the Deliverable Energy
4.3.3 Calculation of the Net Generated Energy
4.4 Optimizing the Net Generated Energy
4.4.1 Basic Steps
4.4.2 Optimization for a Specific Case
4.4.3 Optimization
4.5 Conclusion
References
5 Electrostatic Harvesters with Inductor
5.1 Preliminary Analysis Steps
5.1.1 Inductor-Based Charge Transfer
5.1.2 Large Inductance
5.1.3 Small Inductance
5.2 The Impact of Miniaturizing the Inductor
5.2.1 An Inductor-Based V:C-A:S Harvester
5.2.1.1 The Circuit, Signals, and QV Diagram
5.2.1.2 The Net Generated Energy
5.2.1.3 The Conduction Losses
5.2.1.4 Energy Plots
5.2.1.5 Experimental Results
5.2.2 An Inductor-Based C:C-S:S Harvester
5.2.2.1 The Circuit, Signals, QV Diagram
5.2.2.2 The Net Generated Energy
5.2.2.3 The Conduction Losses
5.2.2.4 Energy Plots
5.2.2.5 Experimental Results
5.2.2.6 Comparison of C:C-S:S and V:C-A:S Harvesters
5.3 A C:C-S:S Electrostatic Harvester with a Miniature Inductor
5.3.1 The Circuit, Signals, QV Diagram
5.3.2 The Net Generated Energy
5.3.3 The Conduction Losses
5.3.4 Energy Plots
5.3.5 Experimental Results
5.3.6 Comparison with Conventional Harvesters
5.3.6.1 Theoretical Comparison
5.3.6.2 Experimental Comparison
5.4 Experimental Setup
5.4.1 Required Components
5.4.1.1 Harvester Core
5.4.1.2 Control Block
5.4.1.3 Measuring Configuration
5.4.2 Implemented Experimental Setup
5.5 Conclusion
References
Conclusion