1. VISVESVARAYA TECHNOLOGICAL UNIVERSITY
TECHNICAL SEMINAR
on
“Wireless Power Transmission Technology”
BACHELOR OF ENGINEERING IN
ELECTRONICS AND COMMUNICATION
SUBMITTED BY
K SUNITHA
[XXX17ECXXX]

2. CONTENTS
• Introduction
• What is Wireless Power Transmission?
• History
• Classification
• Invention and Experiments
• Advantages and Disadvantages
• Application
• Conclusion
• Reference

3. INTRODUCTION
 One of the major issues in power system is the losses occurring during the transmission and
distribution of electrical power.
 The percentage of loss of power during transmission and distribution is approximated as 26%.
The main reason for power loss during transmission and distribution is the resistance of wires used
in grid.
According to the World Resources Institute (WRI), India’s electricity grid has the highest
transmission and distribution losses in the world – a whopping 27-40%.
 Tesla has proposed methods of transmission of electricity using electromagnetic induction.

4. What is Wireless Power Transmission?
 As the word wireless means “without wire”.
 The transmission of energy from one place to another without using wires.
 Wireless transmission is useful in cases where interconnecting wires are
inconvenient, hazardous or impossible.

5. The development history of wireless power transfer
 Wireless power transmission has undergone three stages from generation to development.
STAGE 1:
 The end of the 19th Century ,Nikola Tesla proposed the
method of wireless transmission of electric power.
 One of the greatest breakthroughs of science at that
time.
 Tesla was able to transfer energy from one coil to
another coil.
 He managed to light 200 lamps from a distance of
40km.
 Tesla began construction of a large high-voltage coil
facility, the Wardenclyffe Tower.
 Built the Wardenclyffe tower which could broadcast
power wirelessly using far-field techniques.
 A prototype transmitter for a "World Wireless System“.
Fig: Wardenclyffe Tower

6. STAGE 2:
 In 1975, the first MPT experiment was launched in Venus laboratory. The radio frequency
2.388GHz of 450kW can be transmitted to a distance of 1.6km and its wireless transmission
efficiency is 8.1%.
 He fed 300 Kw power to the Tesla coil resonated at 150 kHz. The RF potential at the top sphere
reached 100 MV. Unfortunately, he failed because the transmitted power was diffused to all
directions with 150 kHz radio waves whose wave length was 21 km.
Fig: First Ground-to-Ground MPT experiment in 1975

7. STAGE 3:
 The idea of Tesla is taken in to
research after 100 years in 2007 by a
team led by Marin Sorgasik from
MIT.
 A group of engineers at MIT came up
with the idea to use resonant
induction to transmit power
wirelessly.
 The project is named as ‘WiTricity’.
Experiment demonstrated at MIT. A 60W light bulb
lit from source at a distance of 2m from load.

8. Wireless Power Transfer Technology Principle
 The most diffused principle of the WPT technique, it converts the
amount of power into an alternative type of energy.
 In the above Figure, each WPT technique involves three main parts
such as the transmitter, receiver, and coupling devices.
Fig: Schematic block diagram of the WPT system

9. Classification of WPT System
 Near field or non-radiative techniques: power is transferred over short distances by magnetic
fields using inductive coupling between coils of wire, or by electric fields using capacitive
coupling between metal electrodes.
 Far-field or radiative techniques: power is transferred by beams of electromagnetic radiation,
like microwaves or laser beams. These techniques can transport energy longer distances but must
be aimed at the receiver.
It’s also called as power beaming.
WIRELESS POWER
TRANSFER
Non-
Radiative Radiative

10. Types of WPT
 Near-field techniques
 Inductive Coupling
 Resonant Inductive Coupling
 Air Ionization
 Far-field techniques
 Microwave Power Transmission
 Laser Power Transmission

11. Inductive Coupling
Transfer of energy by mutual
induction using primary and
secondary coil. Ex-Transformer
It is the oldest and most widely used
wireless power technology and
virtually the only one so far which is
used in commercial products.
Example: Wireless charging pad,
Electric brush.
Fig: Inductive Coupling
Fig: Example of Inductive Coupling

12. Working of wireless charging mobile
Wireless charging works by transferring energy from
the charger to a receiver in the back of the phone via
electromagnetic induction.
They typically have to be in close proximity to each
other and correctly aligned over the top of each
other, although a set orientation is normally not
necessary.

13. Resonant Inductive Coupling
Combination of Inductive
Coupling and Resonance.
Resonance: Phenomena of
amplification that occurs when
frequency of a system equals to
that of natural frequency.
Resonance makes two objects
interact very strongly.
Fig: Resonant Inductive Coupling

14. Example of RIC
By using resonant induction one coil can send electricity to several receiving coils as long
as they all resonate at same frequency.

15. Air Ionization
Air ionizes to transfer electrical
energy at field of 2.11MV/m.
Air ionizes when there is only a
high field.
Not feasible for practical
implementation.
Example: Natural lightening.

16. Microwave Power Transmission
• Transfer of energy by electromagnetic waves.
• Microwave is a form of electromagnetic wave having wavelength from 1 millimeter
to 1meter.
• Microwaves produced at 2.45 GHz by using Magnetron.
• Through this type of Power station we can get 5 to 10 G-Watts power.
Fig: Microwave System

17. Transmission Process
AC to DC
Conversion
DC to
Microwave
Conversion
Transmits
through
medium
Microwave
to DC
Conversion
DC to AC
Conversion
Transmitting
Antenna
Receiving
Antenna

18. Laser Power Transmission
Transfer of energy by converting energy into a laser beam.
It is highly directional. Power is beamed at the receivers end and converted
back into electrical energy.
It is also known as “Power Beaming Technology”.
This technology used in military weapons and aerospace application.
Example:

19. Solar Power Satellites
Objective: Converts solar energy into electrical energy in space and transmits to a
recetenna on Earth using Microwaves. Recetanna will convert the Microwaves to low
power and beam them to the desired receiving antennas. Microwave will then be
converted into electrical energy to be used by consumer.
Fig: Solar Power Satellite Fig: Recetanna in US

20. INVENTION AND EXPERIMENTS OF WPT
Intel’s Demonstration:
• Intel demonstrated a captivating technology that has the potential
to eliminate the need for power cords, chargers or batteries.
• The chip maker wirelessly powered a 60-watt light globe from
three feet away with 75 percent efficiency.
• Intel hopes to one day use the technology to power laptops and
other portable devices. The research project at Intel, led by Joshua
R. Smith aims to build upon this work.
In the 1980s, Canada's Communications Research Centre created
a small airplane that could run off power beamed from the Earth.
• The unmanned plane, called the Stationary High Altitude Relay
Platform (SHARP), was designed as a communications relay. Rather
flying from point to point, the SHARP could fly in circles two
kilometers in diameter at an altitude of about 13 miles.
• Most importantly the aircraft could fly for months at a time.
Fig: Experiment at INTEL for WPT
Fig: SHARP unmanned plane could
run off power beamed from the Earth

21. ADVANTAGES OF WPT
 Eliminates the existing transmission line cables, towers and sub stations.
 More freedom of choice of both receiver and transmitters.
 Cost of transmission and distribution become less.
 Power could be transmitted to the places where the wired transmission is not
possible.
 Loss of transmission is negligible level in the Wireless Power Transmission.
 Safer by eliminating the sparking hazard.

22. DISADVANTAGES OF WPT
 Capital Cost for practical implementation of WPT to be very high.
 Interference of microwave with present communication systems.
 Common belief fears about the effect of microwave radiation among peoples.

23. APPLICATIONS OF WPT
1) Electric automobile charging : According to figure charging pad sits on the ground, connected
to a wall-mounted power adapter. All the car parks over it. On the backside of the car there is
a receiver when charger detects the receiver within range, it automatically starts charging.
2) Consumer electronics
3) Home Electrification
4) Industrial purposes
5) Energy to remote areas
6) Solar power satellite
7) Moving target such as fuel free:
airplanes , electric vehicles , moving robots.
Fig: Electric automobile charging

24. CONCLUSION
 The concept of wireless power transmission is a leading innovations in the world.
 This can change the era of wasting lot of copper for using it for home wiring.
 Better than conventional wired transferring wireless transfer saves the energy
consumption and transmission losses.

25. REFERENCES
[1] [2] Rajnish Saxena,” Wireless Power Transmission – The Future of Power Transmission System”,” JACOTECH, Vol
5,2017”.
[3] Satyam Anil Singh, Umeshkumar Prasad, Ravesh Chauhan, Rutvi Thakar,” Wireless Power Transmission”,”
International Advanced Research Journal in Science, Engineering and Technology (IARJSET) Vol. 5, February 2018”.
[4] Yan Wang, Jinwei Qiao, Jing Du, Fei Wang and Wenhao Zhang,” A view of research on wireless power
transmission”,” Journal of Physics: conference series, Vol 1074,2018”.
[9] Mystica Augustine Michael Duke,” WIRELESS POWER TRANSMISSION”, “International Journal of Scientific &
Engineering Research (IJSER), Vol. 5,2014”.
[14] Farhana Haque Sumi, Lokesh Dutta, Dr. Farhana Sarker,” Future with Wireless Power Transfer Technology”,”
Journal of Electrical & Electronic Systems,2018”.

26. THANK YOU