Wireless Energy Transfer.ms
This document was uploaded by user and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this DMCA report form. Report DMCA
Overview
Download & View Wireless Energy Transfer.ms as PDF for free.
More details
- Words: 1,027
- Pages: 13
Wireless Energy Transmission Max Seidman
What is Wireless Energy Transmission? • •
• •
Wireless Energy Transmission is the transmission of energy through the air. Wireless electricity will truly herald our arrival into the wireless age. Wired electricity is the last thing to keep our “wireless” devices dependent on wires, and with its elimination comes the possibility to free our mobile devices from ever needing to be plugged in. Currently, wired electricity powers nearly everything. It travels through wires in the form of Alternating Current electricity, and powers most of our devices in the form of Direct Current electricity. There are 3 major types (1), each with different ranges, methods of transfer, and pros and cons: – Short range; Inductive Coupling – Medium range; Resonant Induction – Long range; Electromagnetic Wave Power Transfer
Short Range Wireless Energy Transmission: Inductive Coupling
What Is Inductive Coupling? • • •
Inductive Coupling is a method for short range wireless energy transfer. Its range can vary, but it’s often very short. Because of its short range it usually is used when the device containing the receiver and the device containing the transmitter are touching.
Short Range Wireless Energy Transmission: Inductive Coupling
How does Inductive Coupling Work? •
Inductive coupling works on the principles of electromagnetism (3): – When a current (electricity) passes through a wire, it generates a magnetic field perpendicular to the wire. – This effect can be magnified through coiling the wire – When a wire is in proximity to a magnetic field, it generates a current in that wire.
• •
Transferring energy between wires through magnetic fields is inductive coupling Magnetic fields decay quickly (2), making inductive coupling effective only at very short ranges.
(3)
(3)
Short Range Wireless Energy Transmission: Inductive Coupling
Applications for Inductive Coupling • Pros: safe, efficient. Cons: Limited range. • Radio-Frequency Identification (RFID) tags (4) are a widespread use for inductive coupling. These tags are used for everything from identifying livestock to anti-theft mechanisms on products in stores. •
Inductive coupling is also used for wireless charging of electronic devices. Although its short range is limiting, several products use inductive coupling to charge, such as electric toothbrushes (1), and charging mats such as Splashpower (5). (5)
Medium Range Wireless Energy Transmission: Resonant Induction
What Is Resonant Induction? •
•
A group of engineers at MIT came up with the idea to use resonant induction to transmit power wirelessly. They deemed their result “WiTricity” (like WiFi) (2). WiTricity can transmit electricity wirelessly at 40% efficiency to about 7 feet.
Medium Range Wireless Energy Transmission: Resonant Induction
How does Resonant Induction Work? •
• •
•
Resonant induction still uses the same principles as magnetic induction (magnetic fields to transfer current) (1), but it uses resonance to increase the range at which the transfer can efficiently take place (2). Everything resonates at a certain frequency, based on its shape and material. Energy transfers easily between resonating objects. An example of this is when an opera singer shatters wine glasses by singing at the frequency at which the glasses resonate. With resonant induction, power is transmitted between two resonating coils.
Medium Range Wireless Energy Transmission: Resonant Induction
Applications for Resonant Induction •
Pros: Safe, fairly efficient, good range: – Magnetic fields interact weakly with biological masses (humans), and energy is only transmitted between resonating objects. – Efficiency can be increased with time, most of the 60% lost is from heat (2) radiated from the coils.
•
Theoretically one stationary coil in a room could power multiple devices with receiving coils (1). No more messy wires, and with widespread enough use it could even eliminate costly batteries.
(1)
Long Range Wireless Energy Transmission: Microwave Power Transfer
What is Microwave Power Transfer?
•
•
Microwave Power Transfer (MPT) is a form of wave power transfer that, obviously, sends energy through the air in the form of microwaves (other forms can use lasers and visible light). MPT has a range miles longer than its inductive counterparts, and it’s being investigated as a way to beam power to space or vice versa (1).
(1)
Long Range Wireless Energy Transmission: Microwave Power Transfer
How does Microwave Power Transfer Work? •
• •
First, microwaves are converted from DC power, and sent via a large transmitter. On the other end, the are “caught” by an even larger receiver and converted to AC power. The technology for the disk shaped rectifying antenna or “rectenna” is relatively new. Pros: very efficient, very long range – The conversion on either side is about 90% efficient, and the transmission is about 95% efficient (8).
•
Cons: Size of antennae, safety? – According to a study done by NASA (9), to transmit energy from space to earth would require a 1km diameter transmitter and a 10km diameter receiver. – Possible health risks associated with beams of microwaves.
Long Range Wireless Energy Transmission: Microwave Power Transfer
Applications for Microwave Power Transfer •
•
Recently a Canadian program sent up SHARP (Stationary High Altitude Relay Platform), a small unmanned aircraft powered completely by energy beamed to it from the ground through microwaves (7). It could stay in the air for months at a time, flying in a 1km radius circle around the power station at an altitude of 21km (7). It could be used to broadcast in a 600km radius, and would be much faster for 2way communications than using satellites (7). Solar Power Satellites (SPS) could also be an application for MPT. Beaming solar energy collected from satellites or solar panels on the moon to Earth could be a solution to our clean energy issues.
The Future • Wireless energy transmission holds great potential for the future. Magnetic induction, resonant induction, and electromagnetic wave power transmission all have applications that could revolutionize the way we live and use electricity. Keep your eyes open for wireless energy technology in new products, and look forward to when everything will truly be wireless.
Sources (1) http://electronics.howstuffworks.com/wireless-power.htm (2) Castelvecchi, D. (July 21, 2007) The Power of Induction, Science News. Vol. 172, Iss. 3; (3) http://science.howstuffworks.com/electromagnet1.htm (4) http://electronics.howstuffworks.com/smart-label1.htm (5) http://www.splashpower.com/ (6) http://web.mit.edu/newsoffice/2007/wireless-0607.html (7) http://www.friendsofcrc.ca/Projects/SHARP/sharp.html (8) http://www.hq.nasa.gov/webaccess/CommSpaceTrans/SpaceCommTransSec38/CommSpacTransSec38.html (9) http://www.nss.org/settlement/ssp/library/1997-Mankins-FreshLookAtSpaceSolarPower.pdf (Background Lightning Bolt) http://www.ellison.com/images/productimages/Lightning-Bolt_13839.gif
What is Wireless Energy Transmission? • •
• •
Wireless Energy Transmission is the transmission of energy through the air. Wireless electricity will truly herald our arrival into the wireless age. Wired electricity is the last thing to keep our “wireless” devices dependent on wires, and with its elimination comes the possibility to free our mobile devices from ever needing to be plugged in. Currently, wired electricity powers nearly everything. It travels through wires in the form of Alternating Current electricity, and powers most of our devices in the form of Direct Current electricity. There are 3 major types (1), each with different ranges, methods of transfer, and pros and cons: – Short range; Inductive Coupling – Medium range; Resonant Induction – Long range; Electromagnetic Wave Power Transfer
Short Range Wireless Energy Transmission: Inductive Coupling
What Is Inductive Coupling? • • •
Inductive Coupling is a method for short range wireless energy transfer. Its range can vary, but it’s often very short. Because of its short range it usually is used when the device containing the receiver and the device containing the transmitter are touching.
Short Range Wireless Energy Transmission: Inductive Coupling
How does Inductive Coupling Work? •
Inductive coupling works on the principles of electromagnetism (3): – When a current (electricity) passes through a wire, it generates a magnetic field perpendicular to the wire. – This effect can be magnified through coiling the wire – When a wire is in proximity to a magnetic field, it generates a current in that wire.
• •
Transferring energy between wires through magnetic fields is inductive coupling Magnetic fields decay quickly (2), making inductive coupling effective only at very short ranges.
(3)
(3)
Short Range Wireless Energy Transmission: Inductive Coupling
Applications for Inductive Coupling • Pros: safe, efficient. Cons: Limited range. • Radio-Frequency Identification (RFID) tags (4) are a widespread use for inductive coupling. These tags are used for everything from identifying livestock to anti-theft mechanisms on products in stores. •
Inductive coupling is also used for wireless charging of electronic devices. Although its short range is limiting, several products use inductive coupling to charge, such as electric toothbrushes (1), and charging mats such as Splashpower (5). (5)
Medium Range Wireless Energy Transmission: Resonant Induction
What Is Resonant Induction? •
•
A group of engineers at MIT came up with the idea to use resonant induction to transmit power wirelessly. They deemed their result “WiTricity” (like WiFi) (2). WiTricity can transmit electricity wirelessly at 40% efficiency to about 7 feet.
Medium Range Wireless Energy Transmission: Resonant Induction
How does Resonant Induction Work? •
• •
•
Resonant induction still uses the same principles as magnetic induction (magnetic fields to transfer current) (1), but it uses resonance to increase the range at which the transfer can efficiently take place (2). Everything resonates at a certain frequency, based on its shape and material. Energy transfers easily between resonating objects. An example of this is when an opera singer shatters wine glasses by singing at the frequency at which the glasses resonate. With resonant induction, power is transmitted between two resonating coils.
Medium Range Wireless Energy Transmission: Resonant Induction
Applications for Resonant Induction •
Pros: Safe, fairly efficient, good range: – Magnetic fields interact weakly with biological masses (humans), and energy is only transmitted between resonating objects. – Efficiency can be increased with time, most of the 60% lost is from heat (2) radiated from the coils.
•
Theoretically one stationary coil in a room could power multiple devices with receiving coils (1). No more messy wires, and with widespread enough use it could even eliminate costly batteries.
(1)
Long Range Wireless Energy Transmission: Microwave Power Transfer
What is Microwave Power Transfer?
•
•
Microwave Power Transfer (MPT) is a form of wave power transfer that, obviously, sends energy through the air in the form of microwaves (other forms can use lasers and visible light). MPT has a range miles longer than its inductive counterparts, and it’s being investigated as a way to beam power to space or vice versa (1).
(1)
Long Range Wireless Energy Transmission: Microwave Power Transfer
How does Microwave Power Transfer Work? •
• •
First, microwaves are converted from DC power, and sent via a large transmitter. On the other end, the are “caught” by an even larger receiver and converted to AC power. The technology for the disk shaped rectifying antenna or “rectenna” is relatively new. Pros: very efficient, very long range – The conversion on either side is about 90% efficient, and the transmission is about 95% efficient (8).
•
Cons: Size of antennae, safety? – According to a study done by NASA (9), to transmit energy from space to earth would require a 1km diameter transmitter and a 10km diameter receiver. – Possible health risks associated with beams of microwaves.
Long Range Wireless Energy Transmission: Microwave Power Transfer
Applications for Microwave Power Transfer •
•
Recently a Canadian program sent up SHARP (Stationary High Altitude Relay Platform), a small unmanned aircraft powered completely by energy beamed to it from the ground through microwaves (7). It could stay in the air for months at a time, flying in a 1km radius circle around the power station at an altitude of 21km (7). It could be used to broadcast in a 600km radius, and would be much faster for 2way communications than using satellites (7). Solar Power Satellites (SPS) could also be an application for MPT. Beaming solar energy collected from satellites or solar panels on the moon to Earth could be a solution to our clean energy issues.
The Future • Wireless energy transmission holds great potential for the future. Magnetic induction, resonant induction, and electromagnetic wave power transmission all have applications that could revolutionize the way we live and use electricity. Keep your eyes open for wireless energy technology in new products, and look forward to when everything will truly be wireless.
Sources (1) http://electronics.howstuffworks.com/wireless-power.htm (2) Castelvecchi, D. (July 21, 2007) The Power of Induction, Science News. Vol. 172, Iss. 3; (3) http://science.howstuffworks.com/electromagnet1.htm (4) http://electronics.howstuffworks.com/smart-label1.htm (5) http://www.splashpower.com/ (6) http://web.mit.edu/newsoffice/2007/wireless-0607.html (7) http://www.friendsofcrc.ca/Projects/SHARP/sharp.html (8) http://www.hq.nasa.gov/webaccess/CommSpaceTrans/SpaceCommTransSec38/CommSpacTransSec38.html (9) http://www.nss.org/settlement/ssp/library/1997-Mankins-FreshLookAtSpaceSolarPower.pdf (Background Lightning Bolt) http://www.ellison.com/images/productimages/Lightning-Bolt_13839.gif
Related Documents
Wireless Energy Transfer.ms
May 2020 1
Wireless Energy Transmission
April 2020 4
Wireless
December 2019 39
Wireless
October 2019 41