The document discusses wireless electricity transfer, also known as witricity, which utilizes coupled resonators for energy transmission without wires. It covers components like transmitter and receiver circuits, methods of wireless power transmission, and the advantages and challenges of adopting this technology. The summary highlights potential applications such as powering homes without grids and the drawbacks related to efficiency and biological concerns.

1. BALOCHISTAN UNIVERSITY OF INFORMATION TECHNOLOGY, ENGINEERING &
MANAGEMENT SCIENCES

2. Group Members:
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3. Introduction
 Wireless electricity or witricity is
the transfer of electric energy or
power over a distance without the
use of wires.
 In order for the energy to be
transferred safely coupled resonators
are used.
 Coupled resonators are two objects
of the same resonant frequency that
exchange energy efficiently without
much leakage .
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4. Block Diagram:
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5. Transmitter Section:
 DC power Source: Step-Down transformer, rectifer circuit convert that
AC voltage to DC signal
 Oscillator Circuit: Royer Oscillator(achieve a high oscillating current for
the transmitter coil).
 Transmitter Coil: L= d2n2/(l+0.45d)
The operating frequency of the oscillator is determined
by the resonance formula given below
F = ½ × π × √ (LC)
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6. Receiver Section:
 Receiver coil:
 Rectifier circuit and a voltage regulator IC: LM 7805 voltage
regulator IC
 The rectifier circuit in the receiver section converts this AC
voltage in to DC
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7. METHODS USED FOR WIRELESS POWER
TRANSMISSION
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 Far Field Electricity Transmission
 Radio/Microwave Power transmission
 Laser Power Transmission
 Near Field Electricity Transmission
 Inductive Charging
 Evanescent/Resonant Wave Coupling

8. INDUCTION (INDUCTIVE COUPLING):
• The simplest example for wireless energy
transfer using this method is the electrical
transformer.
• The main drawback of this method is the short
range.
• A larger, stronger field can be used for energy
transfer over large distance, but this
process is extremely inefficient. Since magnetic
field spreads in all direction, making
a large wastage of energy.
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9.  Power is transmitted when the coils
have same resonant frequency.
 By using resonant induction one coil
can send electricity to several
receiving coils as long as they all
resonate at same frequency.
Resonance : It is the tendency of a system to
oscillate with larger amplitude at some frequencies
than at others.
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10. Why not wires??
 As per studies, most electrical energy transfer is through
wires.
 Most of the energy loss is during transmission
 On an average, more than30%
 In Pakistan, it exceeds by 40%
Why not batteries??
 Estimated that 40 billion
batteries per year add to the
e-waste burden. And of course its
not a good sign.
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11. Advantages and Hurdles
 It can do away with costly grids and substations.
 Homes and cities can be provided power wireless from a central
transmission point.
 Battery operated devices will never run out of power.
 we can have cars that run non-stop with full battery charge.
 We will never have to go to charging station.
 Aircraft can fly nonstop with no need to refuel.
 The future highway could have inductive coils imbedded in the road.
Hurdles/ Disadvantages:
 Biological Drawbacks (line of sight of microwave and Laser signal).
 Economic cost.
 Less efficiency.
 Short distance.(2cm)
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12. Scope
no need of power cables.
no need of charging batteries, or
buying new batteries for your
electrical gadgets.
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13. Gantt Chart
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14. References:
 A next generation power transmission system”, International Journal
of Computer Applications (0975 – 8887) (Volume 1 – No. 13)
 Witricity
 Peter Vaessen,” Wireless Power Transmission”, Leonardo Energy,
September 2009 11/2/14 Wireless Power
 www.wikipedia.com
 http://www.sciencedirect.com/science/journals
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15. Electronics
Engineering
Questions
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