Wireless power transfer involves transmitting electrical energy without wires by generating an electromagnetic field from a transmitter to a receiver. It can eliminate wires and batteries, increasing mobility. Wireless power is useful for powering devices where wires are inconvenient, hazardous, or impossible. Common techniques include inductive coupling using coils, resonant inductive coupling for greater efficiency and range, and far-field methods like microwave transmission over longer distances but requiring line of sight.
Wireless power transmission technology is not a new technology. In 1980, it was demonstrated by Nikola Telsa. ... The name wireless power transmission states the transfer of electrical power from a source to an electrical device without the help of wires. Basically, it involves two coils: a transmitter and a receiver coil.
Wireless power transmission has become the new era in modern technology.The usage of this system is increasing day by day.This slide contains basic elementary topics about wireless power transmission.
Thank you.
Introduction to Wireless Power Transfer and WitricityMln Phaneendra
Wireless Power Transfer has the ability to deliver major advancements in industries and applications that are dependent on physical, contacting connectors, which can be unreliable and prone to failure.
Wireless power transmission technology is not a new technology. In 1980, it was demonstrated by Nikola Telsa. ... The name wireless power transmission states the transfer of electrical power from a source to an electrical device without the help of wires. Basically, it involves two coils: a transmitter and a receiver coil.
Wireless power transmission has become the new era in modern technology.The usage of this system is increasing day by day.This slide contains basic elementary topics about wireless power transmission.
Thank you.
Introduction to Wireless Power Transfer and WitricityMln Phaneendra
Wireless Power Transfer has the ability to deliver major advancements in industries and applications that are dependent on physical, contacting connectors, which can be unreliable and prone to failure.
The India Two Wheeler Market is moderately consolidated, with the top five companies occupying 57.37%. The major players in this market are Bajaj Auto Ltd., Hero MotoCorp Ltd., Honda Motorcycle and Scooter India Pvt. Ltd, Royal Enfield Ltd. India and TVS Motor Company Limited (sorted alphabetically).
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This study being “desk analysis" contains views of various writers and researchers of E-commerce. This study includes the global trends including India as a major source of E-commerce , increasing use of e- commerce in developing nations , reasons behind success of e-commerce as an industry , the use of e-commerce in global sourcing , advantages of E-commerce and several more topics being covered under the project analysis. The use of e-commerce in various countries and their influence over the people or citizens of that country is remarkable.
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The examination reveals that the policy document focuses on the development of introductory courses, professional courses, and vocational courses for the students. The objective of developing courses is to develop a student's attitude and aptitude. It also focuses on creating industry-ready and entrepreneurial orientation among the students. The NEP aims to increase the use of technology in education. There is a provision in the policy, technology or e-learning is the need of the hour (Kaurav, Rajput, & Baber, 2019). The policy also mentions that a National Education Technology Forum needs to be formed so that it could act as a podium where there can be the exchange of ideas on the use and development of technology. Previously, the education policies were offering exposure to the students which, in turn, would help the student to evolve. The current education policy focuses on a student exchange program that provides students with multiple exit points. It is visible from the examination in this study that the effort has been made to evolve the Indian education system and offer students international level pedagogy. Dr Bijaya Kumar Sahoo, Founder, SAI International Education
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The impurities in drug products can be attributed not only to the drug substance or inert ingredients used for formulating a drug product; but they can also be brought into the drug product through the formulation process or by contact with packaging of the various impurities that can be found in drug products.
response of plants to duration and
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Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
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The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
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2. INTRODUCTION
Wireless power transfer (WPT), wireless power transmission, wireless
energy transmission (WET), or electromagnetic power transfer is the
transmission of electrical energy without wires as a physical link. In a
wireless power transmission system, a transmitter device, driven by
electric power from a power source, generates a time-varying
electromagnetic field, which transmits power across space to a receiver
device, which extracts power from the field and supplies it to an
electrical load. The technology of wireless power transmission can
eliminate the use of the wires and batteries, thus increasing the
mobility, convenience, and safety of an electronic device for all users.
Wireless power transfer is useful to power electrical devices where
interconnecting wires are inconvenient, hazardous, or are not possible.
4. What in 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.
5. 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 than 30%
n India, it exceeds 40%
Why WPT?
Reliable
Efficient
Fast
Low maintenance cost
Can be used for short-range or long-range.
6. HISTORY
Nikola Tesla in late 1890s .Pioneer of induction
techniques his vision for “World Wireless System”
The 187 feet tall tower to broadcast energy. All
people can have access to free energy due to
shortage of funds, tower did not operate Tesla
was able to transfer energy from one coil to
another coil He managed to light 200 lamps from
a distance of 40km The idea of Tesla is taken in to
research after 100 years by a team led by Marin
Soljačić from MIT. The project is named as
WiTricity
7. ENERGY COUPLING
The transfer of energy
Magnetic coupling
Inductive coupling
Simplest Wireless Energy coupling is a transformer
TYPES AND TECHNOLOGIES OF WPT
Near-field techniques
Inductive Coupling
Resonant Inductive Coupling
Air Ionization
Far-field techniques
Microwave Power Transmission (MPT)
LASER power transmission
8. INDUCTIVE COUPLING
Primary and secondary coils are not connected with wires.
Energy transfer is due to Mutual Induction
Transformer is also an example Energy transfer devices are
usually aircored Wireless Charging Pad(WCP),electric brushes
are some examples On a WCP, the devices are to be kept,
battery will be automatically charged.
Electric brush also charges using inductive coupling.The
charging pad (primary coil) and the device(secondary coil)
have to be kept very near to each other It is preferred
because it is comfortable. Less use of wires Shock proof.
9. Resonance Inductive Coupling(RIC)
Combination of inductive coupling and resonance.
Resonance makes two objects interact very strongly.
Inductance induces current.
How resonance in RIC?
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 electric field around the
capacitor
Radiation loss will be negligible
Block Diagram of RIC
An Example
10. WiTricity
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%
WiTricity… Some statistics
Used frequencies are 1MHz and 10MHz
At 1Mhz, field strengths were safe for human
At 10MHz, Field strengths were more than ICNIRP standards
11. WiTricity now…
No more helical coils
Companies like Intel are also working on devices that make use of RIC
Researches for decreasing the field strength
Researches to increase the range.
RIC vs. inductive coupling.
RIC is highly efficient
RIC has much greater range than inductive coupling
RIC is directional when compared to inductive coupling
RIC can be one-to-many. But usually inductive coupling is one-to-one
Devices using RIC technique are highly portable.
12. 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
Advantages of near-field techniques
No wires
No e-waste
Need for battery is eliminated
Efficient energy transfer using RIC
Harmless, if field strengths under safety levels
Maintenance cost is less
13. Disadvantages
Distance constraint
Field strengths have to be under safety levels
Initial cost is high
In RIC, tuning is difficult
High frequency signals must be the supply
Air ionization technique is not feasible
Far-field energy transfer
Radiative
Needs line-of-sight
LASER or microwave
Aims at high power transfer
Tesla‟s tower was built for this
14. Microwave Power Transfer(MPT)
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 can not be directly converted to microwave energy
AC is converted to DC first
DC is converted to microwaves using magnetron
Transmitted waves are received at rectenna which rectifies, gives DC as the output
DC is converted back to AC
LASER transmission
LASER is highly directional, coherent
Not dispersed for very long
But, gets attenuated when it propagates through atmosphere
Simple receiver
Photovoltaic cell
Cost-efficient
15. Solar Power Satellites (SPS)
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
Solar energy is captured using photocells
Each SPS may have 400 million photocells
Transmitted to earth in the form of microwaves/LASER
Using rectenna/photovoltaic cell, the energy is converted to electrical energy
Efficiency exceeds 95% if microwave
Rectenna
Stands for rectifying antenna
Consists of mesh of dipoles and diodes
Converts microwave to its DC equivalent
Usually multi-element phased array
16. Rectenna in US
Rectenna in US receives 5000MW of power from SPS
It is about one and a half mile long
Other projects
Alaska‟21
Grand Bassin
Hawaii
LASER vs. MPT
When LASER is used, the antenna sizes can be much smaller Microwaves
can face interference (two frequencies can be used for WPT are 2.45GHz
and 5.4GHz) LASER has high attenuation loss and also it gets diffracted by
atmospheric particles easily.
17. Advantages of far-field energy transfer
Efficient
Easy
Need for grids, substations etc are eliminated.
Low maintenance cost.
More effective when the transmitting and receiving points are along a lineof- sight.
Can reach the places which are remote.
Radiative
Needs line-of-sight
Initial cost is high
When LASERs are used,
◦ conversion is inefficient
◦ Absorption loss is high
When microwaves are used,
◦ interference may arise
◦ FRIED BIRD effect 8/31/2010
18. APPLICATIONS
Near-field energy transfer
Electric automobile charging
Static and moving
Consumer electronics
Industrial purposes
Harsh environment
Far-field energy transfer
Solar Power Satellites
Energy to remote areas
Can broadcast energy globally (in future)
19. CONCLUSION
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.
20.
21. INTRODUCTION
Wireless power transfer (WPT), wireless power transmission, wireless
energy transmission (WET), or electromagnetic power transfer is the
transmission of electrical energy without wires as a physical link. In a
wireless power transmission system, a transmitter device, driven by
electric power from a power source, generates a time-varying
electromagnetic field, which transmits power across space to a receiver
device, which extracts power from the field and supplies it to an
electrical load. The technology of wireless power transmission can
eliminate the use of the wires and batteries, thus increasing the
mobility, convenience, and safety of an electronic device for all users.
Wireless power transfer is useful to power electrical devices where
interconnecting wires are inconvenient, hazardous, or are not possible.
23. What in 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.
24. 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 than 30%
n India, it exceeds 40%
Why WPT?
Reliable
Efficient
Fast
Low maintenance cost
Can be used for short-range or long-range.
25. HISTORY
Nikola Tesla in late 1890s .Pioneer of induction
techniques his vision for “World Wireless System”
The 187 feet tall tower to broadcast energy. All
people can have access to free energy due to
shortage of funds, tower did not operate Tesla
was able to transfer energy from one coil to
another coil He managed to light 200 lamps from
a distance of 40km The idea of Tesla is taken in to
research after 100 years by a team led by Marin
Soljačić from MIT. The project is named as
WiTricity
26. ENERGY COUPLING
The transfer of energy
Magnetic coupling
Inductive coupling
Simplest Wireless Energy coupling is a transformer
TYPES AND TECHNOLOGIES OF WPT
Near-field techniques
Inductive Coupling
Resonant Inductive Coupling
Air Ionization
Far-field techniques
Microwave Power Transmission (MPT)
LASER power transmission
27. INDUCTIVE COUPLING
Primary and secondary coils are not connected with wires.
Energy transfer is due to Mutual Induction
Transformer is also an example Energy transfer devices are
usually aircored Wireless Charging Pad(WCP),electric brushes
are some examples On a WCP, the devices are to be kept,
battery will be automatically charged.
Electric brush also charges using inductive coupling.The
charging pad (primary coil) and the device(secondary coil)
have to be kept very near to each other It is preferred
because it is comfortable. Less use of wires Shock proof.
28. Resonance Inductive Coupling(RIC)
Combination of inductive coupling and resonance.
Resonance makes two objects interact very strongly.
Inductance induces current.
How resonance in RIC?
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 electric field around the
capacitor
Radiation loss will be negligible
Block Diagram of RIC
An Example
29. WiTricity
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%
WiTricity… Some statistics
Used frequencies are 1MHz and 10MHz
At 1Mhz, field strengths were safe for human
At 10MHz, Field strengths were more than ICNIRP standards
30. WiTricity now…
No more helical coils
Companies like Intel are also working on devices that make use of RIC
Researches for decreasing the field strength
Researches to increase the range.
RIC vs. inductive coupling.
RIC is highly efficient
RIC has much greater range than inductive coupling
RIC is directional when compared to inductive coupling
RIC can be one-to-many. But usually inductive coupling is one-to-one
Devices using RIC technique are highly portable.
31. 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
Advantages of near-field techniques
No wires
No e-waste
Need for battery is eliminated
Efficient energy transfer using RIC
Harmless, if field strengths under safety levels
Maintenance cost is less
32. Disadvantages
Distance constraint
Field strengths have to be under safety levels
Initial cost is high
In RIC, tuning is difficult
High frequency signals must be the supply
Air ionization technique is not feasible
Far-field energy transfer
Radiative
Needs line-of-sight
LASER or microwave
Aims at high power transfer
Tesla‟s tower was built for this
33. Microwave Power Transfer(MPT)
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 can not be directly converted to microwave energy
AC is converted to DC first
DC is converted to microwaves using magnetron
Transmitted waves are received at rectenna which rectifies, gives DC as the output
DC is converted back to AC
LASER transmission
LASER is highly directional, coherent
Not dispersed for very long
But, gets attenuated when it propagates through atmosphere
Simple receiver
Photovoltaic cell
Cost-efficient
34. Solar Power Satellites (SPS)
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
Solar energy is captured using photocells
Each SPS may have 400 million photocells
Transmitted to earth in the form of microwaves/LASER
Using rectenna/photovoltaic cell, the energy is converted to electrical energy
Efficiency exceeds 95% if microwave
Rectenna
Stands for rectifying antenna
Consists of mesh of dipoles and diodes
Converts microwave to its DC equivalent
Usually multi-element phased array
35. Rectenna in US
Rectenna in US receives 5000MW of power from SPS
It is about one and a half mile long
Other projects
Alaska‟21
Grand Bassin
Hawaii
LASER vs. MPT
When LASER is used, the antenna sizes can be much smaller Microwaves
can face interference (two frequencies can be used for WPT are 2.45GHz
and 5.4GHz) LASER has high attenuation loss and also it gets diffracted by
atmospheric particles easily.
36. Advantages of far-field energy transfer
Efficient
Easy
Need for grids, substations etc are eliminated.
Low maintenance cost.
More effective when the transmitting and receiving points are along a lineof- sight.
Can reach the places which are remote.
Radiative
Needs line-of-sight
Initial cost is high
When LASERs are used,
◦ conversion is inefficient
◦ Absorption loss is high
When microwaves are used,
◦ interference may arise
◦ FRIED BIRD effect 8/31/2010
37. APPLICATIONS
Near-field energy transfer
Electric automobile charging
Static and moving
Consumer electronics
Industrial purposes
Harsh environment
Far-field energy transfer
Solar Power Satellites
Energy to remote areas
Can broadcast energy globally (in future)
38. CONCLUSION
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.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59. INTRODUCTION
Wireless power transfer (WPT), wireless power transmission, wireless
energy transmission (WET), or electromagnetic power transfer is the
transmission of electrical energy without wires as a physical link. In a
wireless power transmission system, a transmitter device, driven by
electric power from a power source, generates a time-varying
electromagnetic field, which transmits power across space to a receiver
device, which extracts power from the field and supplies it to an
electrical load. The technology of wireless power transmission can
eliminate the use of the wires and batteries, thus increasing the
mobility, convenience, and safety of an electronic device for all users.
Wireless power transfer is useful to power electrical devices where
interconnecting wires are inconvenient, hazardous, or are not possible.
61. What in 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.
62. 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 than 30%
n India, it exceeds 40%
Why WPT?
Reliable
Efficient
Fast
Low maintenance cost
Can be used for short-range or long-range.
63. HISTORY
Nikola Tesla in late 1890s .Pioneer of induction
techniques his vision for “World Wireless System”
The 187 feet tall tower to broadcast energy. All
people can have access to free energy due to
shortage of funds, tower did not operate Tesla
was able to transfer energy from one coil to
another coil He managed to light 200 lamps from
a distance of 40km The idea of Tesla is taken in to
research after 100 years by a team led by Marin
Soljačić from MIT. The project is named as
WiTricity
64. ENERGY COUPLING
The transfer of energy
Magnetic coupling
Inductive coupling
Simplest Wireless Energy coupling is a transformer
TYPES AND TECHNOLOGIES OF WPT
Near-field techniques
Inductive Coupling
Resonant Inductive Coupling
Air Ionization
Far-field techniques
Microwave Power Transmission (MPT)
LASER power transmission
65. INDUCTIVE COUPLING
Primary and secondary coils are not connected with wires.
Energy transfer is due to Mutual Induction
Transformer is also an example Energy transfer devices are
usually aircored Wireless Charging Pad(WCP),electric brushes
are some examples On a WCP, the devices are to be kept,
battery will be automatically charged.
Electric brush also charges using inductive coupling.The
charging pad (primary coil) and the device(secondary coil)
have to be kept very near to each other It is preferred
because it is comfortable. Less use of wires Shock proof.
66. Resonance Inductive Coupling(RIC)
Combination of inductive coupling and resonance.
Resonance makes two objects interact very strongly.
Inductance induces current.
How resonance in RIC?
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 electric field around the
capacitor
Radiation loss will be negligible
Block Diagram of RIC
An Example
67. WiTricity
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%
WiTricity… Some statistics
Used frequencies are 1MHz and 10MHz
At 1Mhz, field strengths were safe for human
At 10MHz, Field strengths were more than ICNIRP standards
68. WiTricity now…
No more helical coils
Companies like Intel are also working on devices that make use of RIC
Researches for decreasing the field strength
Researches to increase the range.
RIC vs. inductive coupling.
RIC is highly efficient
RIC has much greater range than inductive coupling
RIC is directional when compared to inductive coupling
RIC can be one-to-many. But usually inductive coupling is one-to-one
Devices using RIC technique are highly portable.
69. 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
Advantages of near-field techniques
No wires
No e-waste
Need for battery is eliminated
Efficient energy transfer using RIC
Harmless, if field strengths under safety levels
Maintenance cost is less
70. Disadvantages
Distance constraint
Field strengths have to be under safety levels
Initial cost is high
In RIC, tuning is difficult
High frequency signals must be the supply
Air ionization technique is not feasible
Far-field energy transfer
Radiative
Needs line-of-sight
LASER or microwave
Aims at high power transfer
Tesla‟s tower was built for this
71. Microwave Power Transfer(MPT)
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 can not be directly converted to microwave energy
AC is converted to DC first
DC is converted to microwaves using magnetron
Transmitted waves are received at rectenna which rectifies, gives DC as the output
DC is converted back to AC
LASER transmission
LASER is highly directional, coherent
Not dispersed for very long
But, gets attenuated when it propagates through atmosphere
Simple receiver
Photovoltaic cell
Cost-efficient
72. Solar Power Satellites (SPS)
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
Solar energy is captured using photocells
Each SPS may have 400 million photocells
Transmitted to earth in the form of microwaves/LASER
Using rectenna/photovoltaic cell, the energy is converted to electrical energy
Efficiency exceeds 95% if microwave
Rectenna
Stands for rectifying antenna
Consists of mesh of dipoles and diodes
Converts microwave to its DC equivalent
Usually multi-element phased array
73. Rectenna in US
Rectenna in US receives 5000MW of power from SPS
It is about one and a half mile long
Other projects
Alaska‟21
Grand Bassin
Hawaii
LASER vs. MPT
When LASER is used, the antenna sizes can be much smaller Microwaves
can face interference (two frequencies can be used for WPT are 2.45GHz
and 5.4GHz) LASER has high attenuation loss and also it gets diffracted by
atmospheric particles easily.
74. Advantages of far-field energy transfer
Efficient
Easy
Need for grids, substations etc are eliminated.
Low maintenance cost.
More effective when the transmitting and receiving points are along a lineof- sight.
Can reach the places which are remote.
Radiative
Needs line-of-sight
Initial cost is high
When LASERs are used,
◦ conversion is inefficient
◦ Absorption loss is high
When microwaves are used,
◦ interference may arise
◦ FRIED BIRD effect 8/31/2010
75. APPLICATIONS
Near-field energy transfer
Electric automobile charging
Static and moving
Consumer electronics
Industrial purposes
Harsh environment
Far-field energy transfer
Solar Power Satellites
Energy to remote areas
Can broadcast energy globally (in future)
76. CONCLUSION
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.
