microwave transmission

1. Submitted by:
AMIT KUMAR
Dept: EEE
Roll:B110409EE
Nit Calicut
(2011-2015)

2. Overview
 Wireless power transmission(WPT)
 Why WPT
 Microwave Transmission
 Microwave vs. laser transmission
 Rectenna
 Solar power Satellite
 Current Developments
 Advantages of WPT
 Disadvantages of WPT
 Applications

3. HISTORY OF WPT
 Nicola Tesla considered as the
Father of WPT.
 Tesla applied the principle of
resonance to transfer power wirelessly.
 William Brown of Raytheon
company used MWPT for wireless
powered helicopter.
www.pancea-bocarf.org

5. METHODS OF SPACE BASED WPT
 Far Term Space Systems to beam power to Earth
 Light-Wave Systems
 Radio-Wave WPT System
 In case of light-wave system we use laser beam for
wireless power transmission.
 In case of radio-wave power transmission systems we
use microwaves for wireless power transmission.

9. Microwave Transmission.
Radio wave
VLF, LF

11. WPT USING MICROWAVES(Continued)
 Microwaves have frequencies between 300 MHz (0.3 GHz) and 300 GHz (1m to
1mm).
 The atmosphere is transparent at longer wavelengths (e.g. 100 MHz), opaque
at shorter wavelengths (e.g. 400 GHz), but becomes transparent again when
you go up to 500 THz (light).
 Higher frequency more power will transmitted.

12. wireless energy transmission via LASER for
solar energy
•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.
•To increase efficiency of power station.
•Reduce the size of power plants.
•Increase power generation capacity of power plant.
Solar power
intensity is just-
137mW/cm2

13. Electrical Power Demand
0.0
0.2
0.4
0.6
0.8
1.0
1.2
0 6 12 18 24/0
Time (Hours)
NormalizedPower/Area
Normalized Output from SPS
(Non-Tracking Arrays)
Normalized Output from Sun
Normalized Total Output
6 12 18 24/0
Time (Hours)
6 12 18 24
Time (Hours)
+ =
Typical Electricity Demand
Total Power at PV ReceiverPV Power from WPT-LightPV Power from Sunlight
Sunlight + Laser-PV WPT = ~ Power Requirement
Photo-Voltaic (PV) Power Station Receives Both

14. COMPARISON
ATTRIBUTE MWPT LASER
INTERFERENCE Radio frequency
interference
None except
astronomical
APERTURE SIZE Large, so system is very
large
small
ATTENUATION Penetrates clouds and
rains
Stopped by clouds
EFFICIENCY (SPACE) HIGH IMPROVING
EFFICIENCY (GROUND) HIGH IMPROVING
SAFETY Keep aircraft out of
beam
Safe
PERCEPTION Public fears of “cooking” Government fears of
“weapons”

15. Solar power satellite(SPS)
 1968’s idea for Solar power Satellites proposed by Peter
Glaser
 Would use microwaves to transmit power to earth from
space
 To efficiently make use of renewable energy i.e. solar
energy
 Solar powered satellites are placed in geostationary orbits
 Solar power from the satellite is sent to earth using a
microwave transmitter
 Received at a “Rectenna” located on Earth

17. Architecture of Solar power
Satellite(SPS)

18. 1.solar panel: solar panels are the main source of DC
power.
2. Microwave Generator : Vacuum Tubes
(magnetron, klystron) and Microwave Power Module
(MPM)) and Semiconductor Microwave transmitters and
amplifiers (GaAs MESFET, SiC MESFET, HFET, and InGaAs).
3.waveguide circulator and adaptor: wave
guide circulator which protects the microwave
source from reflected power and connected with the
microwave power source through the Coax – Waveguide
Adapt

19. 4. Tuner: matches the impedance between the transmitting antenna
and the microwave source to minimize reflected loss and maximum
power deliver to antenna
5. Direction coupler and transmitting antenna: The attenuated
signals will be then separated based on the direction of signal propagation
by Directional Coupler. The transmitting antenna radiates the power
uniformly through free space to the rectenna.

20. SCHEMATIC DIAGRAM

21. Rectenna
 An antenna comprising a mesh of dipoles and
diodes for absorbing microwave energy from a
transmitter and converting it into electric
power
 Microwaves are received with about 85%
efficiency
 Around 5km across (3.1 miles)
 95% of the beam will fall on the rectenna

22. MICROSTRIP RECTENNA
www.smartmatech.com
• The diagram shows a micro strip rectenna
•A large rectenna consists of array of many such dipole elements.

23. RF-DC CONVERSION(RECTENNA)
 RECTENNA- Rectifying Antenna
 Its a special type of antenna used to convert microwave energy into DC.
 The simplest crystal radio receiver, employing an antenna and
a demodulating diode (rectifier), is actually a rectenna - although it discards
the DC component
 A simple rectenna element consists of a dipole antenna with an
RF diode connected across the dipole elements.
 RF diode for power rectifier and gain control stage .
 The diode rectifies the AC current induced in the antenna by the microwaves,
to produce DC power, which powers a load connected across the diode.

24. Advantages over Earth based Solar
Power
 More intense sunlight
 In geosynchronous orbit, 36,000 km (22,369 miles) an SPS
would be illuminated over 99% of the time
 No need for costly storage devices for when the sun is not
in view
 Waste heat is radiated back into space
 Power can be beamed to the location where it is needed,
don’t have to invest in as large a grid
 No air or water pollution is created during generation

25. Current Development
 Project in development in Japan
 Goal is to build a low cost
demonstration model by 2025
 8 Countries along the equator
have agreed to be the site of a
rectenna
 Will not be in geosynchronous
orbit , instead lower orbit 1100 km
(683 miles)
 Much cheaper to put a satellite in
a low orbit

26. Advantages of WPT
 Efficient
 Easy
 The power could be transmitted to the remote places where the wired
transmission is not possible
 Need for grid, high tension transmission lines, substations are eliminated
 Low maintenance cost
 Power theft would be not possible at all
 The power failure due to short circuit and fault on cables would never
exist in the transmission.
 The cost of transmission and distribution would become less
 The cost of electrical energy for the consumer would be reduced also
 Wireless charging would also possible
 Vehicles would be driven using WPT, no need of fuel.

27. Problems
Issues identified during the DOE study
 Complexity—30 years to complete
 Size—6.5 miles long by 3.3 miles wide
Transmitting antenna ½ mile in diameter(1 km)
.Cost—prototype would have cost $74 billion
Microwave transmission
 Interference with other electronic devices
 Health and environmental effects
 Would require a network of hundreds of satellites
 Protection from comet ,asteroid, lightning.
 Would make telecommunications companies into power companies

28. How to build smart power system
with the help of WET??
•Huge solar tower to be set up to set up at geostationary
orbit.
•Structure of solar tower- Huge tower attach with directly
pumped solar LASER diodes , mirrors , lens ,controlling
system for beam.
•Receiving power stations all over India.
•Power station – array of high efficiency high power solar
cell.
•Controlling station.
•So energy conversion –solar energy to concentrated light
energy – electrical energy.

29. How the power system will work?
•The huge solar towers drectly convert solar energy
into concentrated LASER beam.
•LASER beam will be concentrated on receiving power
station.
•Highly efficient solar cells or rectenna will convert it
into electric energy.
.
•With this technology it is expected 1GW of power can
be generated.
•Each SPS would have 400 million solar cells

30. How it will increase the efficiency of power
plants??
•More energy will be concentrated on small area.
•Receiving energy will lie in useful energy band
in spectrum.
•High efficiency of LASER diode.
•Input to panels will be sunlight+ concentrated
beam.
•Improve losses due to transmission via wires.
•Efficiency of system will be 35% to 40% much
more than present plants.

31. A plan for India
•Can be used as mobile power station
•A controlling station for satellite on the
earth.
•Receiving power stations in each state.
•Specially remote areas like
lakhshwadeep Andmaan Nicobar islands,
North Eastern region military
areas,Jammu Kashmir.
•Power should be supplied to these
station periodically.
•If any region suffers from power
shortage beam should be directed to that
region.
•Power can be supplied to neighboring
countries.

32. Limitations & solutions
 cost
 Effect on atmosphere
 Effect on living beings
 Delay in application due to
restricted development in
nanotechnology
 Placing in geostationary orbit
 Project should be multinational
 Frequency can be adjusted to
infra-red
 Area should be restricted or
established in desert area .
 More research in
nanotechnology.
 Multi-mission project.

33. SOLAR POWER SATELLITE
A CONCEPTUAL VIEW OF THE SYSTEM
www.pedain.com

34. GROUND RECTENNA FOR SPS SYSTEM
www.airspacemag.com

36. CONCLUSION
 The system efficiency is very low to be used for practical purpose with
current technology.
 Emergence of META MATERIALS may change the scenario in future.
 Metamaterial antennas use metamaterials to increase performance of
miniaturized (electrically small) antenna systems.

37. Specifications
 Possible power generation of 5 to 10 gigawatts
 “If the largest conceivable space power station were built and
operated 24 hours a day all year round, it could produce the
equivalent output of ten 1 million kilowatt-class nuclear power
stations.”
 Collector area must be between 50 (19 sq miles) and 150 square
kilometers (57 sq miles)
 50 Tons of material
 Current rates on the Space Shuttle run between $3500 and $5000 per
pound
 50 tons (112,000lbs)=$392,000,000

38. Wireless Power
Transmission
for Rover Operations
in Shadowed Craters
Solar Power
Generation on
Mountaintop
Direct
Communication
Link
Moon’s Orbit
North Pole (SEE BELOW)
South Pole (SEE BELOW)
Sun Rays are Horizontal
at North & South Poles
•NEVER shine into Craters
•ALWAYS shine on Mountain
POSSIBLE ICE DEPOSITS
•Craters are COLD: -300F (-200C)
•Frost/Snow after Lunar Impacts
•Good for Future Human Uses
•Good for Rocket Propellants

39. Typical parameters of the transmitting antenna of
the SPS

40. Microwaves
 Frequency 2.45 GHz microwave beam
 Retro directive beam control capability
 Power level is well below international safety standard
 Highest efficiency at 2.45 GHz above 90%
 One proposal is to capture the asteroid into earth orbit and convert it into
150 solar power satellites of 5 GW each or the larger asteroid 1999 AN10
which is 50x the size of Apophis and large enough to build 7,500 5-Gigawatt
Solar Power Satellites

41. DARRK ENERGY

42. References
 http://www.ijaiem.org/volume2issue10/IJAIEM-2013-10-21-026.pdf
 http://www.ijcaonline.org/archives/number13/274-43
 http://scholarlyoa.files.wordpress.com/2013/03/wireless-power-
transmission.pdf
 http://iopscience.iop.org/1742-6596/439/1/012046/pdf/1742-
6596_439_1_012046.pdf

43. This is dedicated to my INSPIRATION in my
college.
thanks for energize me .