This document outlines the contents of a thesis on wireless power transmission (WPT). It includes 6 chapters that cover the history and theory of WPT, how electricity can be transformed for WPT, the near and far field theories that enable WPT, technologies for transmitters and receivers, recent technological trends, applications and advantages of WPT, and the future scope of the technology. The chapters discuss topics such as losses in wired power systems, historical developments of WPT, how wireless power works, theories such as induction and electromagnetic coupling, antennas and rectennas used for WPT, efficiency of power transfer and conversion, interactions with the atmosphere and space, automatic wireless charging applications, and safety considerations of WPT.

1. CONTENTS
CERTIFICATE………………………………………………………………….…...ii
ACKNOWLEDGEMENT……………………………………………………….......iii
ABSTRACT…………………………………………………………………...….…iv
LIST OF FIGURES………………………………………………………………....vii
CHAPTER 1: WIRELESS POWER TRANSMISSION……………………...…1-8
1.1 Introduction ……………………………………………………..…………1
1.2 Why do we go for wireless power transmission (WPT) system ……………1
1.2.1 Losses in the wired system ………..………………………...……....1
1.3 Historical revolution of Wireless Power Transmission …….………....…….3
1.4 What is WPT ……………………………………………………………..…6
1.5 How does wireless power work? ……………………………………............7
1.6 Need of WPT ………………………………………………………….….....7
CHAPTER 2: IDEA OF TRANSFORMING ELECTRICITY TO WPT……....9-12
2.1 Electricity ………………………………………………...……...……….…..9
2.2 Magnetism ……………………………………………......…..........................9
2.3 Electromagnetism ………………………………………...........……………..9
2.4 Magnetic induction………………..............................................………...….10
2.5 Energy/power coupling …………...……………………...........…………….10
2.6 WPT technology …………………………………………......……………...11
CHAPTER 3: THEORIES ON WPT …………………….……..…………….....13-23
3.1 Near field theory ………………………………………..........…………......13
3.1.1 Electrical conduction principle ……………………….....…….……...13
3.1.2 Induction principle (non resonant energy transfer) ..………................15
3.1.3 Electrostatic induction principle ……………….....…………….……16
3.1.4 Electro-dynamic induction ……………………......………..…….…..17
3.1.5 Experimental demonstration of evanescent coupling at MIT...............18
3.2 Far Field Theory ……………………………………..………………….…18
3.2.1 Microwave Power Transmission (MPT) ……………...…..…….…19
3.2.2 Applications ………………………………………….........…….…20
3.2.2.1 WTP for space solar ………………………………………...20
3.2.2.2 Power transfer bridging ………………………………......…21
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2. 3.2.3 Safety issues ………………………………………….….............22
CHAPTER 4: TRANSMITTERS AND RECIEVERS …………………..…..24-27
4.1 Antennas for Microwave Power Transmission ………..………...…........24
4.2 Recent technologies for transmitters ……………………..………..….....24
4.2.1 Magnetron …………………………………………..….............25
4.2.2 Semiconductor amplifier ……………………...……………,,…25
4.3 Wireless Power Transmission – Receivers and Rectifiers …….…….......26
4.3.1 Recent technologies of Rectenna ……………..………..…..……26
4.3.2 Recent technologies of Rectenna array………………......………26
4.3.3 Efficiency ………………………...……………………......…….26
4.3.3.1 RF DC conversion efficiency ...……….…........………...27
4.3.3.2 Beam collection efficiency ……………....……....…..….27
CHAPTER 5: RECENT TECHNOLOGICAL TRENDS.…………...……...28-29
5.1 Retro directive beam control………………….………….................……28
5.2 Environmental issues …………………….………….………………......28
5.3 Interaction with Atmosphere ……………..…….……….............,.....…..28
5.4 Interaction with Space Plasmas ...……….....…………….………,,….....29
CHAPTER 6: APPLICATIONS, ADVANTAGES AND FUTURE……......30-33
6.1 Applications ……………………………………………………….…..30
6.1.1 Automatic wireless power charging ………………….…......,....30
6.1.2 Consumer electronics …………………………………….........30
6.1.3 Industrial……………………………………..…………….........30
6.1.4 Transportation ………………………….…...………...…….…..31
6.2 Other applications ……………………………….……………...……...31
6.3 Advantages and disadvantages …………………………………..….....31
6.4 Safety and Future scope …………………………………………...…....32
6.4.1 Is WPT technology safe? ………………………...………….…...32
6.4.2 Future scope of WPT ……………………………..……….....…..33
CONCLUSION ……………………………………………………………..…34
REFRENCES ………………………………………………….…………........35
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