2. Contents
What do you mean by Wi Tricity?
Need of Witricity
History of wireless power
Witricity basics
Detailed Principle
How safe is Witricity?
What’s the future of witricity?
Advantages
Application
Limitation
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3. AIM OF WIRELESS POWER
The Ultimate Aim of this project is Transmit
the Power By Wireless mode which can be
used in electrical/electronic devices for general
use.
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4. FIRST OPERATION OF
WITRICITY
On June 7’ 07, a team of researchers at MIT
announced the successful operation of Witricity
concept.
They had lit up a 60W with a power from a source at
the distance of 7 feet(over 2m) with no wires.
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5. History of Wireless Power
In 1899, Sir Nikola Tesla
Proposed a method of Wireless
Power Transmission.
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6. In1899,Tesla achieved
a major breakthrough
in his work at Colorado
by transmitting 100
million volts of electric
power wirelessly over a
distance of 26 miles to
light up a bank of 200
light bulbs and run one
electric motor.
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7. In Layperson’s Terms
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Wireless electricity is the transfer of power to a
device over the air.
— It will allow devices to be powered or charged (with the
proper wireless attachments) without being plugged into
a wall outlet or docked in a charging station.
8. 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.
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9. Three major types
Short range; Inductive Coupling
Medium range; Resonant Induction
Long range; Electromagnetic Wave Power
Transfer
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10. Short Range Wireless Energy Transmission:
Inductive Coupling
What Is Inductive Coupling?
Inductive Coupling is a method for short range
wireless energy transfer.
Its range can vary, but it’s often very short.
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11. How does Inductive Coupling
Work?
Inductive coupling works on the
principles of electromagnetism:
When a current (electricity) passes
through a wire, it generates a magnetic
field perpendicular to the wire.
When a wire is in proximity to a
magnetic field, it generates a current in
that wire.
Magnetic fields decay quickly ,
making inductive coupling effective
only at very short ranges.
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12. Medium Range Wireless Energy
Transmission: Resonant Induction
What Is Resonant Induction?
A group of engineers at MIT came up with the
idea to use resonant induction to transmit
power wirelessly. They deemed their result
“WiTricity” (like Wi-Fi) . WiTricity can transmit
electricity wirelessly at 40% efficiency to about
7 feet.
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13. HOW WIRELESS POWER
WORKS
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1. Magnetic coil (transmitter) is housed in a box and can
be set in wall or ceiling.
2. Transmitter, powered by mains, resonates at a specific
frequency.
3. Electromagnetic waves transmitted through the air.
4. Second magnetic coil (receiver) fitted in laptop/TV etc
resonates at same frequency as first coil and absorbs
energy.
5. Energy charges the device.
16. Now the questions are?
Is WiTricity safe?
How much power can be transferred?
What about the range of transferred?
How efficient is WiTricity?
What's the Future of WiTricity?
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18. Current Uses
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Wireless charging pads
Electric Toothbrushes:
Both of these techniques use small electric
fields to charge the devices.
Haier America Digital Products group has
already developed a HDTV that transmits
electricity and the HD signal, making the TV
completely wireless.
19. Advantages
Safe, fairly efficient, good range:
Magnetic fields interact weakly with biological
masses (humans),
Efficiency can be increased with time, most of
the 60% lost is from heat radiated from the coils.
Theoretically one stationary coil in a room could
power multiple devices with receiving coils.
No more messy wires, and with widespread
enough use it could even eliminate costly
batteries.
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20. 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.
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21. What's the Future of WiTricity?
MIT's WiTricity is only 40 to 45% efficient and
they have to be twice as efficient to
compete with the traditional chemical
batteries.
The researchers have said that in another
five years time, they will come up with a
WiTricity system for commercial use.
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