Nikola Tesla proposed wireless power transmission in 1899 and successfully lit over 200 lamps from over 40 km away in his Colorado Springs experiment using resonant induction and high frequency currents transmitted through the ground. In 2007, MIT engineers revived interest in wireless power by demonstrating resonant inductive coupling to transmit 60W of power over 2 meters without wires. Wireless power transmission systems use techniques like inductive coupling, resonant inductive coupling, microwave power transmission, and laser power transmission to transfer energy through the air or ground without wires. Potential applications include wirelessly charging electric vehicles and powering devices without plugging them in.

1. WIRELESS POWER
TRANSMISSION
By:
Hafiz Hussain(2012119)
Hassan Raza(2012143)
Junaid Ahmad(2012159)
Khawaja Zain(2012161)

2. Introduction
Transmission and distribution losses
Loss of energy generated in wires
Nicola Tesla

3. History of Wireless Power
In 1899, Sir Nikola Tesla Proposed a
method of Wireless Power Transmission.
He enlighted 200 lamps at the distance of 40
km, Wirelessly !
Nikola Tesla – The Genius
Colorado springs experiment

4. Earth current transmission
Wireless Tower
Charged by high frequency and high voltage apparatus
High frequency AC Current discharged
Conduction, Earth surface shell
Tesla Coil
Electrical resonant transformer circuit
High frequency output illuminates fluorescent tubes

5. 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.

6. Experiment demonstrated at MIT.
A 60W light bulb lit from source at a distance of 2m from load.

7. What is WPT ?
definition is :
 “Transmission of energy through the air”.
 A system of two electromagnetic resonators
coupled mostly through their magnetic fields.

8. Types of WPT
Near-field techniques
Inductive Coupling
Resonant Inductive Coupling
Air Ionization
Far-field techniques
Microwave Power Transmission (MPT)
LASER power transmission
8

9. Inductive coupling
Primary and secondary coils- not connected
with wires.
Energy transfer - due to Mutual Induction.
9

10. Resonance Inductive Coupling(RIC)
Same concept as Inductive coupling just that the coils
operate at resonant frequency leading to efficient
transfer of energy over a larger distance.
 Interacts weakly with extraneous off resonant objects.
Radiation loss will be negligible

11. 11

12. Resonant Inductive Coupling

13. Air Ionization
Toughest technique under near-field energy transfer
techniques
Air ionizes only when there is a high field
Needed field is 2.11MV/m
Natural example: Lightening
Not feasible for practical
implementation.

14. Microwave Power Transmission
(MPT)
 SPS Idea proposed by Petel Glaser in 1968
 Satellite in Geosynchronous Orbit

15. Microwave Power Transmission
(MPT)
Microwaves produced at 2.45 GHz by using Magnetron
Rectenna is used for collecting these Microwaves (One and
half mile long)
 Rectenna converted these Microwaves in DC power with
antenna and rectifier
Through this type of Power Station, we can get 5 to 10 G-Watts
power.
Power efficiency up to 85%.

16. 5,000 MW Receiving Station (Rectenna). This station is
about a mile and a half long.

17. Laser Power Transmission
 Energy conversion –solar energy to concentrated light
energy – electrical energy.

18. Laser Power Transmission
Long distance transmission possible.
Solar energy- Not a concentrated source of energy.
Losses due to scattering of light.
Presently only 3% of solar energy is being utilized.
High efficiency about 50% to 75%.
With this technology it is expected 1GW of power can be
generated.

19. 19
Applications
In Electric Automobiles

20. Applications
 Direct Wireless Power
 No device needs wires
 For TVs, toasters or any form of
Immobile devices

Automatic Wireless Charging Pad
 Device with rechargeable batteries
 charges itself
 Criteria: Close Contact

21. WPT CONCERNS
Will it harm me?
Will it harm the environment?
NO

22.  No wires
 No Energy-waste as compared to dumped used batteries
 Need for battery is eliminated
Maintenance cost is less
22
Advantages of WPT

23. Distance constraint
23
Disadvantages

24. Initial cost is high
In RIC, tuning is difficult(L & C Values for Resonance)
Air ionization technique is not feasible( small distance,
High voltage, )
24
Disadvantages

25. CONCLUSION
Transmission without wires- a reality
Efficient (MIT experiment more than 60%)
Energy crisis can be decreased
In near future, world will be completely wireless