1. Wireless Power Transmission
Presented By
Soumya Prateek Muni
1001104052
Department Of Electrical Engineering
Government College Of Engineering , Keonjhar

2. What is wireless power transmission(WPT)?
Why is WPT?
History of WPT
Types of WPT
Techniques to transfer energy wirelessly
Advantages and disadvantages
Applications
Conclusion
References
Overview

3. What is WPT?
The transmission of energy from one
place to another without using wires
Conventional energy transfer is using
wires
But, the wireless transmission is made
possible by using various technologies

4. As per studies, most electrical energy
transfer is through wires.
Most of the energy loss is during
transmission
• On an average, more than 30%
• In India, it exceeds 40%
Why Not Wires?

5. Reliable
Efficient
Fast
Low maintenance cost
Can be used for short-range or long-
range.
Why WPT?

6. Nikola Tesla in late 1890s
His vision for “World Wireless System”
The 187 feet tall tower to broadcast energy
All people can have access to free energy
Shortage of fund lead to nonoperation
He used to lamp 200 lights from 40 km distance
History

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

8. The transfer of energy
Magnetic coupling
Inductive coupling
Simplest Wireless Energy coupling is a transformer
Energy Coupling

9. Primary and secondary coils are not connected with
wires.
Energy transfer is due to Mutual Induction
Wireless Charging Pad(WCP) ,Electric
Brushes are some examples.
Inductive coupling

10. The capacitor and inductor forms the resonator. Charge
oscillates between inductor (as magnetic field) and
capacitor (as electric field.)
This type of oscillation is called
resonance if the reactance's
of the inductor and capacitor
are equal.
Resonance Inductive Coupling(RIC)

11. 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
electricfield around the capacitor.
Radiation loss will be negligible
How resonance in RIC?

12. An example

13. 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
Air Ionization

14. Advantages:
No wire, No e-waste
Need for battery eliminated
Efficient & Harmless
Disadvantages:
Distance constraint
Field should be under safety level
High initial cost
Tuning is difficult in RIC
Advantages & Disadvantages of
near-field techniques

15. Transfers high power from one place to another. Two
places being in line of sight usually
Steps:
Electrical energy to microwave energy
Capturing microwaves using rectenna
Microwave energy to electrical energy
AC is converted to DC first
DC is converted to microwaves using magnetron
Microwave Power Transfer(MPT)

16. Transmitted waves are received at rectenna which
rectifies, gives DC as the output
DC is converted back to AC
Rectenna:
Stands for rectifying antenna
Consists of mesh of dipoles and diodes
Converts microwave to its DC equivalent
Usually multi-element phased array
MPT(Continued….)

17. LASER is highly directional, coherent
Not dispersed for very long
But, gets attenuated when it propagates
through atmosphere
Simple receiver
Photovoltaic cell
Cost-efficient
LASER transmission

18. To provide energy to earth’s increasing energy
need
To efficiently make use of renewable
energy i.e., solar energy
SPS are placed in geostationary orbits
Each SPS may have 400 million
photocells
Efficiency exceeds 95%
if microwave is used.
Solar Power Satellites (SPS)

19. Advantages & Disadvantages of
Far Field Technology
Advantages:
Efficient , Easy
Need for grid eliminated
Low maintenance cost
More effective when the
transmitting and
receiving points are along
a line-of-sight
Can reach the places
which are remote
Disadvantages:
Radiate
When LASERs are used,
conversion is inefficient
Absorption loss is high
When microwaves are
used,
interference may arise

20. Qi(Chee) is a interface standard
Developed by Wireless Power
Consortium
It works for a distance up to
40mm(1.6inches)
Comprises a transmission pad
& a compatible receiver
The Qi Standard

21. Near-field energy transfer
Electric automobile charging
Static and moving
Consumer electronics
Industrial purposes
Harsh environment
Applications

22. Far-field energy transfer
Solar Power Satellites
Energy to remote areas
Can broadcast energy
globally (in future)
Applications(Continued…..)

23. Based on RIC , Led by MIT’s Marin Soljačić
Energy transfer wirelessly for a
distance just more than 2m.
Coils were in helical shape
No capacitor was used
Efficiency achieved was around 40%
Used frequencies are 1MHz &10MHz
Intel is working on it
Wireless Electricity(WiTricity)

24. Transmission without wires- a reality
Efficient
Low maintenance cost. But, high initial cost
Better than conventional wired transfer
Energy crisis can be decreased
Low loss
In near future, world will be completely
wireless
Conclusion

25. “Wireless Power Transmission”, Vol No.-45,
Electronics For U –August-2013
Peter Vaessen,” Wireless Power
Transmission”, Leonardo Energy, September
2009
C.C. Leung, T.P. Chan, K.C. Lit, K.W. Tam and
Lee Yi Chow, “Wireless Power Transmission
and Charging Pad”
References

26. White Paper on Solar Power Satellite (SPS)
Systems, URSI, September 2006
Richard M. Dickinson, and Jerry Grey, “Lasers
for Wireless Power Transmission”
David Schneider, “Electrons unplugged”, IEEE
Spectrum, May 2010
References(Continued……)

27. THANK YOU!