witricity - wireless electricity - wireless energy transfer - seminar report

–

–

–

–

Nikola Tesla’s Wardenclyffe Tower (Tesla Tower) Tesla’s Wireless Bulb

ever, Newton’s gravitational law, Watt’s steam engine, Thomson’s bulb and many more. But a

Today, as we can see the word ‘wireless’ is common in day – –

“W ”

In the late 1800’s and early 1900’s, at the dawn of the electrification of the modern world,

arin Soljačić

’

earth’s magnetic field are examples of objects having

“capture” some portion of that

—

Christian Oersted’s discovery of magnetic field around a

…

cas letter “e” for voltage.

ge: e = N(dΦ/dt)

Ω, the intensity oscillations I when the system is driven with a driving frequency ω

systems. Γ

λ

f = v/λ

’s Wireless Bulb

one at the ‘sender end’ and one at ‘receiver end’. The

Where ω1, 2 are the individual frequencies, Γ1, 2 are the Resonance widths (Decay rates) due tohe objects’ intrinsic (absorption, radiation etc.) losses, and ‘κ’ is the coupling coefficient

ω1=ω2 and Γ1=Γ2 normal modes of the combined system are split by 2κ.

ween the two objects takes place in time Pi/κ and is nearlyloss rates (κ>> Γ1, 2).

κ /sqrt (Γ1, 2)

The desired optimal regime κ/sqrt (Γ1,2)>>1 is called “StrongCoupling” regime.There is No change in Energy, unless κ/Γ

sending coil (or “primary winding”) induces another current in a receiving coil (or “secondarywinding”). The two coils must be very close together, and may even overlap, but the coils do not “charging pads” which require that the object being charged be placed directly on top of, or very

receiver by “cranking power” “Directed radiation”,

machines use “magnetic resonance imaging” “Resonant Coupling” must “resonance” in “MRI”

power consumption to a power saving “idle” state.

concrete are essentially “transparent” to magnetic fields—

“wrap around” many metallic obstacles that might otherwise block the magnetic fields.

— — “The body really

technology doesn’t give rise to radio

technology operates in a “load following” mode,

—

—

technology is designed for Original Equipment Manufacturers (OEM’s) to embed

Reduce product failure rates by fixing the ‘weakest link’:

Use efficient electric ‘grid power’ directly instead of inefficient battery charging.

hotspots … while devices are in use and mobile.

screen TV’s, digital picture

unsightly cables and “wallwart” power supplies.

etc… eliminating disposable batteries and a

“joints” (robots, packaging machinery, assembly machinery, machine tools) …

underwater, etc.) … where it is impractical or impossible to

–

An article published in the Science Magazine as “Wireless Power Transfer via StronglyCoupled Magnetic Resonances” by Andre kurs, Science 317,

“Efficient NonRadiative Midrange Energy Transfer” by Aristeidies karalis, Marlin

F. Valone, “Tesla’ s Wireless Energy... For the 21 Direct TV!!!”

James O. McSpadden, “Wireless Power Transmission Demonstration”, Texas A&M

rych Arthur (Setauket, NY), “System and method for wireless electrical powertransmission”,

Joe T. Howell, et. al , “Advanced receiver / converter experiments for laser wirelesspower transmission”