1. WITRICITY
-WIreless elecTRICITY
Submitted By
SAILA KURICHETI

2. In this paper.... 1) History of Wireless power. 2) Need of Witricity.
3) Basic Principle.
4) Classification based on range of distance .
5) Advantages and disadvantages.

3. History of Wireless Power:
In 1899, Sir Nikola Tesla Proposed a method of Wireless Power Transmission.
As it is in Radiative mode, most of the Power was wasted and has less efficiency.
 The efficient mid range power transfer concept is Witricity. In this model source and load are in Magnetic resonance so there is no power loss.

4. The forgotten invention is reborn in 2007
RESONANCE COUPLING
A group of engineers at MIT came up with the idea to use resonant induction
to transmit power wirelessly.
“Resonance", a phenomenon that causes an object to vibrate when energy of a certain frequency is applied.

5. Need of Witricity:
Now a days there is a Rapid development of autonomous electronics like Laptops, Cell-phones, House-hold robots, electric cars and all those devices typically rely on chemical energy storage(Battery) . As they are becoming daily needs to present generation, Wire less energy transfer would be useful for many applications as above and they need mid range energy.

6. What is Witricity.? Electricity without wires Magnetic loop antennas Electromagnetic near-field

7. How does Witricity Work?
Near-field inductive coupling through magnetic fields
Resonant coupling through strong magnetic field between coils in resonance.
Interact weakly with surrounding objects (like biological tissue)

8. Basic Principle:
The basic principle involved in Witricity concept is, Two objects having same resonating frequency and in Magnetic resonance at Strongly coupled regime tend to exchange energy , while dissipating relatively little energy to the extraneous off-resonant objects.

9. CLASSIFICATION Wireless power transmission is possible via
short range distances and
long range distances
Long range transmission makes use of micro waves.
It can also be done using laser but with great loss in efficiency.

10. Witricity Today
Based on this principle , MIT powered 60 watt light bulb from 2 meters (7 ft) at 40% efficiency.
MIT researchers used two tesla coils separated by 2 meters to demonstrate the working of witricity principle.
MIT researchers are working on improving the efficiency , distance between the coils.

11. Experimental Design:
Our experimental scheme consists of two Self-resonant coils. One coil (source coil) is coupled inductively to the supply ; the other (device coil) is coupled inductively to a resistive load. Self-resonant coils rely on the interplay between distributed inductance and distributed capacitance to achieve resonance.

13. Witricity Tomorrow
1) Power from mains to antenna, which is made of copper
2) Resonates 10MHz (electromagnetic waves)
3) Tunnel up to 2m (6.5ft)
4) Electricity received by antenna, also resonating at 10MHz.
5) Energy transfers to laptop absorbed by antenna. People/other objects not affected as they are not resonating at 10MHz

14. To charge the electric cars , vehicles in highways.

16. LONG RANGE TRANSMISSION
Witricity can be used for wireless transmission of solar power via long range distances from solar power satellites in space to earth using micro waves and rectanna.
Advantages:
Unaffected by the day night cycle, weather or seasons.
This is an eco friendly system..
It is boon for the devices which uses midrange power.
Limitations:
The resonance condition should be satisfied and if any error exists, there is no possibility of power transfer.
If there is any possibility of very strong ferromagnetic material presence causes low power transfer due to radiation.

17. LONG RANGE TRANSMISSION
Long range transmission uses receiver , transmitter on earth , space respectively for transmitting,receiving micro waves.
Transmitter on solar power satillite employs anti-rectanna for converting electrical energy to micro waves.
While Receiver on earth uses rectanna for extracting the electrical energy(D.C power) from micro waves.

18. RECTANNA Rectanna can be explained briefly by the equation
rectanna=antenna + rectifier .
Antenna is used to receive (or) transmit the micro waves.
Rectifier makes the necessary conversion from micro waves to D.C power and vice versa.

19. WORLD IN OUR FUTURE

20. ADVANTAGES No need of line of sight No need of power cables,batteries
Doesnt interfere with radio waves
Negative health implications
Highly efficient if within the strong magnetic field range

21. DISADVANTAGES Currently successful only for short range distance
Setting up of solar power satellite in space
Large Size of rectanna on earth

22. CONCLUSION
Witricity is in development stage, lots of work is to be done to use it for wireless power applications.
Currently the project is looking for power transmission in the range of 100w.
Before the establishment of this technology the detailed study must be done to check whether it cause any harm on any living beings.