Witricity by Shashank
- 1. WITRICTY NAME: SHASHANK H USN NO: 1RE11EE099 GUIDE: DR. B.P. DIVAKAR REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 2. CONTENTS Introduction History of Witricity First Experiment on Witricity Working of Witricity Advantages & Disadvantages Safety concerns Application Design References REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 3. INTRODUCTION • Process of transferring electric energy or power over distance without wires through the air. • Eliminates the use of cables for transmission of power. • Known as “WiTricity” and “ Wireless Power Transmission”. • The term WiTricity was used for a project that took place at MIT, led by Marin Soljačić in 2007. • A Witricity system consists of a Witricity transmitter and the receiver which works on the principle of Radio Receivers. • Witricity uses resonant magnetic field while reducing the wastage of power. REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 4. HISTORY OF WITRICITY • In 1899,Sir Nikola Tesla proposed a method of Wireless Power Transmission. • Enlighten 200 lamps at the distance of 40 km. But only 15% efficiency was achieved. • As it is in Radiative mode , most of the Power was wasted and had less efficiency. • Wardenclyffe Tower built on Long Island, NY in 1904. • Tesla’s vision to transmit power and information. • Destroyed in 1917. REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 5. FIRST EXPERIMENT ON WITRICITY • A group of engineers at MIT came up with the idea to use resonant induction to transmit power wirelessly. • MIT powered 60 watt light bulb from 2 mts (7 ft) at 40% efficiency. • One coil (source coil) is coupled inductively to an oscillating circuit; the other (device coil) is coupled inductively to a resistive load. • The interplay between distributed inductance and distributed capacitance achieves resonance. REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 6. WORKING OF WITRICITY • Magnetic coil is housed in a box and can be set in wall or ceiling. • Antenna A resonates at a specific frequency. • Electromagnetic waves transmitted through the air. • Second magnetic coil (Antenna B) resonates at same frequency as first coil and absorbs energy. REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 7. BLOCK DIAGRAM REPRESENTATION REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 8. ADVANTAGES • No need of power cables and batteries. • Does not interfere with radio waves. • Wastage of power is small. • Negative health implications. • Highly efficient than electromagnetic induction • Less costly. REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 9. DISADVANTAGES • Wireless power transmission can be possible only in few metres. • Over-heating occurs because of different voltages. • Refitting old equipment or purchasing new equipment. • Energy Theft. REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 10. SAFETY CONCERNS • Shock prevention. • Magnetic fields do not cause any damage to any living beings. • May increase a person’s body temperature or may heat body tissues and may stimulate nerve and muscle tissues REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 11. APPLICATIONS • Consumer Electronics Automatic wireless charging of mobile electronics (phones, laptops, game controllers, etc.)in home, car, office. • Industrial Direct wireless power and communication interconnections at points of use in harsh environments(drilling, mining, underwater, etc.) • Transportation Automatic wireless charging for existing electric vehicles: golf carts, industrial vehicles. REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 12. REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department In the Future
- 13. DESIGN Design Aspects: Design of coil • The LC circuit must be driven, for example by an AC power supply, for resonance to occur. The frequency at which this equality holds for the particular circuit is called the resonant frequency. • In order to achieve a resonance frequency in the oscillator circuit the inductive reactance and the capacitive reactance of the resonator coil will equal such that: XL= XC (1) Where ωL = 1÷ ωC And ω = 2×π×f REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 14. DESIGN CONTINUED • Capacitive Reactance: XC = 1÷ 2fC (2) • Inductive Reactance: XL = 2fL (3) • Resonant Circuit formula: 4π2 f2 LC = 1 (4) Where f= 1÷2 π(LC)½ (5) XC = Capacitive Reactance in ohms XL = Inductive Reactance in ohms f= Frequency in hertz L = Inductance in Henry C = Capacitance in farads REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 15. REFERENCES • Hirai, J., Kim, T.-W. and Kawamura, A. “Wireless transmission of power and information and information for cableless linear motor drive.” IEEE Trans. on power electronics 15, 21 (2000). • Esser, A. and Skudelny, H.-C. “A new approach to power supplies for robots.” IEEE Trans. on industry applications 27, 872 (1991). • Ka-Lai, L., Hay, J. W. and Beart, P. G. W. “Contact-less power transfer.” U.S. patent number 7,042,196, issued in May 2006. (SplashPower Ltd., www.splashpower.com) • Fernandez, J. M. and Borras, J. A. “Contactless battery charger with wireless control link.” U.S. patent number 6,184,651, issued in February 2001. REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department
- 16. THANK YOU REVA INSTITUTE OF TECHNOLOGY AND MANAGEMENT, BANGALORE-560064 Electrical and Electronics Engineering Department