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Witricity is nothing but wireless electricity.
Transmission of electrical energy from one
object to another without the use of wires is
called Witricity.
Because of Witricity some of the devices won’t
require batteries to operate .
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 team from Massachusetts Institute
of Technology, who call their invention
‘WiTricity‘.
In the first successful trial of its kind,
the team was able to illuminate a 60-
watt light bulb 7ft away.
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4. Types of wireless energy transfer
techniques are:-
Short range– Inductive coupling
Mid range– Resonance Inductive coupling
Long range-Microwave Transmission
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5. MICROWAVE POWER
TRANSMISSION
• Transfer high power from
one place to another
• Electrical energy
converted
into microwave energy
using magnetron
• Capturing microwave using recteena
• Conversion of microwave energy into electricity
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6. LASER POWER TRANSMISSION
* LASER highly directional and coherent
* But, gets attenuated if obstacle between source
and load
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8. ORBITTING SATELLITE -COLLECTS
SOLAR ENERGY ON SPACE
ADVANTAGES- HIGHER COLLECTION
RATE EXPOSED 24 hr/day
DISADVANTAGES- HIGH COST
EXTRA COST OF MAINTENANCE
10. Inductive coupling
Primary and secondary coils- not
connected with wires.
Energy transfer - due to Mutual
Induction.
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11. Inductive coupling…
• Transformer is also an example
• Energy transfer devices are usually air-cored
• Wireless Charging Pad(WCP),electric brushes
are some examples
• On a WCP, the devices are to be kept, battery
will be automatically charged.
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12. Resonance Inductive Coupling(RIC)
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Combination of inductive coupling and
resonance
Resonance makes two objects interact
very strongly
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13. How resonance in RIC?
• Coil provides the inductance
• Capacitor is connected parallel to the coil
• Energy will be shifting back and forth
between magnetic field surrounding the
coil and electric field around the capacitor
• High resonant frequency
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14. RIC vs. inductive coupling
• RIC is highly efficient
• RIC has much greater range than inductive
coupling
• RIC is directional when compared to inductive
coupling
• RIC can be one-to-many. But usually inductive
coupling is one-to-one
• Devices using RIC technique are highly portable
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27. IN ROBOTS
Eliminating the need for disposable batteries or a
power cord connecting the helmet
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28. Advantages of WITRICITY
• No wires
• Highly Resonent strong coupling provides high Efficiency over Distance
• Energy transfer via magnetic near field can penetrate and wrap arround obstacle
• Non –Radiative energy transfer is safe for people and animals
• Scable Design Enables solution from milli watts to kilowatts
• Maintenance cost is less
• Lower Frequency Operation
• Practical for short Distance
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29. Disadvantages
• Distance constraint
• High power Loss
• Non directionality
• Field strengths have to be under safety levels
• Initial cost is high
• In RIC, tuning is difficult
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