1 WITRICITY

witricity
Witricity is nothing but wireless electricity.
Transmission of electrical energy from one object to another without the use of wires is called as Witricity
Story behind WITRICITY
The story started late one night a few years ago. It was probably the sixth time that month that MIT Professor Marin Soljacic was awakened by his mobile phone beeping battery low. At that time it occurred to him that there is electricity wired all through his house, office-everywhere. He think about- how it is possible to use electricity without using wires…
Eureka!

Electrical Resonance
Tendency of a circuit system to oscillate at a maximum amplitude for a certain resonance frequency.
Likely to occur when impedance between input and output is minimized.
Increases the strength of interaction between two related devices
Electricity
Electricity is a general term that encompasses a variety of phenomena resulting from the presence and flow of electric charge.

magnetism
Magnetism is a force that acts at a distance due to a magnetic field. This field is caused by moving electrically charged particles or is inherent in magnetic objects such as magnet.


Electromagnetic induction is the production of voltage across a conductor moving through a magnetic field.
Electromagnetism is one of the four fundamental interactions of nature, along with strong interaction, weak interaction and gravitation. It is the force that causes the interaction between electrically charged particles; the areas in which this happens are called electromagnetic fields
Energy/Power Coupling: Energy coupling occurs when an energy source has a means of transferring energy to another object


Resonant Magnetic Coupling: Magnetic coupling occurs when two objects exchange energy through their varying or oscillating magnetic fields. Resonant coupling occurs when the natural frequencies of the two objects are approximately the same.

Coupled resonators
Two resonant objects of the same resonant frequency tend to exchange energy.

Coupled resonators are said to be operate in strongly coupled regime to avoid material absorption and radiative loss.
How wireless technology could work
Power from mains to antenna, which is made of copper.


Antenna resonates.


Tails' of energy from antenna 'tunnel' up to 5m (16.4ft).


Electricity is picked up by laptop's antenna.
Witricity technology
The Transfer of Electricity from one place to another without wires is known as “Witricity”.

There is witricity power sources(transmitter) and capture devices(receiver).

Power source provides power to the devices where as capture device captured it to work.

Power source and capture devices are specially designed magnetic resonators.

Magnetic resonators efficiently transfer power over large distance via the magnetic near-field.



Experiment conducted
Experimental Design: Experimental scheme consists of two Self-resonant coils. One coil (source coil) is coupled inductively to an oscillating circuit; 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.

Is witricity safe
WiTricity’s technology is a non-radiative mode of energy transfer, relying instead on the magnetic near field. Magnetic fields interact very weakly with biological organisms—people and animals—and are scientifically regarded to be safe. WiTricity products are being designed to comply with applicable safety standards and regulations.
First japan made wireless tv
applications
Automatic wireless charging of mobile electronics in home, car, office,...while devices are in use and mobile.

Direct wireless powering of stationary devices…eliminating expensive custom wiring, unsightly cables and “wall-wart” power supplies.
Automatic wireless charging and for high tech military systems.
Direct wireless powering and automatic wireless charging of smartcards.
Direct wireless power interconnections and automatic wireless charging for implantable medical devices .
Direct wireless powering and automatic wireless charging ofconsumer Appliance, mobile robots, etc.

Industrial app.
Robots, package machinery, assembly machinery, machine tools.

Direct wireless power and communication interconnections at points of use in harsh environments.

Direct wireless power for wireless sensors and actuators, eliminating the need for expensive power wiring or battery replacement and disposal.
advantages
No need of line of sight.
No need of power cables and batteries.
Does not interfere with radio waves.
Negative health implications.
Less costly.

Disadvantages
Wireless power transmission can be possible only in few meters.

Efficiency is only about 40%.
New theory
The efficiency of power transfer can be improved significantly using one or more relay resonators. This approach enhances the performance of the present two-resonator witricity systems and allows transmitting power over a longer range, following a curved path, and using smaller resonators.

Witricity team
conclusion
The transmission of power without wires is not a theory or a mere possibility, it is now a reality. The electrical energy can be economically transmitted without wires to any terrestrial distance.
Wireless transmission of electricity have tremendous merits like high transmission integrity and Low Loss (90 – 97 % efficient) and can be transmitted to any where in the globe and eliminate the need for an inefficient, costly, and capital intensive grid of cables, towers, and substations.
The system would reduce the cost of electrical energy used by the consumer and get rid of the landscape of wires, cables, and transmission towers. It has negligible demerits like reactive power which was found insignificant and biologically compatible.