1. Technical Seminar Presentation
On
WIRELESS TRANSMISSION POWER
USING ELECTROMAGNET
”
Presented By:
Name: Balaji Koushik S
1VI20EC009
VIII Sem ‘A’ Section
Department of ECE, VemanIT
Guided By:
Name: Dr. Reddy Sudharshana K
Designation: Associate Professor
Department of ECE, Vemana IT
DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING
2. WHAT IS IT?
• Wireless power transfer (WPT), wireless energy transmission (WET), or electromagnetic power
transfer is the transmission of electrical energy without wires as a physical link.
• In this system a transmitter device, transmits power to a receiver device, through the phenomenon
of electromagnetic induction.
3. HISTORY
• In 1890, Nikola Tesla concluded that power could be transferred between two objects wirelessly
via an electromagnetic field.
• He demonstrated wireless transmission by "electrostatic induction" during an 1891 lecture
at Columbia College.
• He had a vision for “world wireless system”
• Wardenclyffe Tower- Tower built to achieve this
purpose
4. NECCESSITY OF WPT
Environmental protection and economical
Reduction of transmission losses
Charging of multiple devices
Prevents corrosion and sparking
Maintenance cost is reduced
Eliminating charging cords - provision for compact and portable
devices
Reduced power failures
5. TYPES OF WPT
NEAR FIELD TECHNIQUES
Inductive Coupling
Resonant Inductive Coupling
Capacitive Coupling
FAR FIELD TECHNIQUES
Microwave Power Transmission
Laser Power Transmission
6. NEAR FIELD TECHNIQUES
INDUCTIVE COUPLING
• In this system there is a transmitter coil and a receiver coil which represent the model of a
transformer and power transfer is through electromagnetic induction.
• The coefficient of coupling is given by k=M/sqrt(L1*L2).
APPLICATIONS
Electric tooth brushes, shavers, cardiac pacemakers, insulin pumps etc..
Wireless charging pads to charge electronic devices
To charge electric vehicles
MERITS
Reduction in copper losses and heat generation
Shock proof
DEMERITS
The coils must be very close to each other (within centimeters)
It is usually one to one
Flux confinement cores have to be used
8. RESONANT INDUCTIVE COUPLING
It is the wireless transmission of electrical energy between two magnetically coupled coils that are part of a
resonant circuit (also called LC Circuit or tank circuit)
Resonance is a phenomenon in which a material naturally oscillates at a specific frequency, called
“resonant frequency”
MERITS
Better charging range
Ability to charge multiple devices at the same time.
Higher efficiency when compared to inductive coupling
DEMERITS
Relatively low efficiency due to flux leakage
Greater circuit complexity
Because of the high operating frequencies, potential electromagnetic
interference (EMI) challenges.
APPLICATIONS
Charging portable devices , biomedical implants, electric vehicles,
powering buses, trains, MAGLEV, RFID, smartcards.
9. CAPACITIVE COUPLING
• It is also referred to as electric coupling. Power is transferred by electrostatic induction between
two electrodes forming a capacitance with the intervening space as the dielectric
• The amount of power transferred increases with the frequency and the capacitance between the plates, which
is proportional to the area of the smaller plate and inversely proportional to the separation.
MERITS
• Reduced interference
• Alignment requirements between the source and load are less critical.
DEMERITS
• Used in a low power applications only
• Electric fields interact strongly with most materials, including the human
body causing excessive electromagnetic field exposure
APPLICATIONS
• Charging battery powered portable devices
• Wireless power transfer in biomedical implants
• Means of transferring power between substrate layers in integrated circuits.
10. • MICROWAVE POWER TRANSMISSION(MPT)
AC is converted to DC
DC is converted to microwaves using a magnetron
MERITS
• Long distance power transmission
• High conversion efficiencies (rectenna efficiency is >95%)
DEMERITS
• High frequency rays- Injurious to health
• Expensive as compared to other methods
APPLICATIONS
• Aiding renewable energy , by means of satellites collecting sunlight and sending power back to
Earth.
• In 1964, a miniature helicopter propelled by microwave power had been demonstrated
• Battery-free cameras and temperature sensors were powered using transmissions from Wi-Fi
routers
FAR-FIELD (RADIATIVE) TECHNIQUES
11. LASERS
• The laser beam of high intensity is thrown from some specific distance to the load end.
• At the load end highly efficient photo voltaic cells convert light energy of the laser into electrical
energy.
MERITS
• Compact size
• No radio-frequency interference
• Access control
DEMERITS
• Laser radiation is hazardous
• PV cells have limited efficiency - 40-50% only
• Atmospheric absorption and scattering -up to 100% losses.
• Direct line of sight with the target is a must
APPLICATIONS
• Lightweight unmanned model plane powered by a laser beam.
• Used in military and aerospace works (space elevator)
12. IMPLEMENTATION
PowerLight Technologies - American engineering firm transmitting power via lasers.
- Primary products are power-over-fiber
New Zealand- Powerco signed a deal with Emrod
- Uses MPT-2KW, 70%efficiency
Aglaya, an Indian Defence Company's Research and Development unit has used WET to charge devices
in the range of 3 -12 Volts under any weather conditions.
Inductive coupling WPT was adopted by the Hitachi Maxell and Murata companies to charge an iPad.
WPT was used to charge an electric bus by Hino Motors Ltd. and Showa Aircraft Industry
Toyota Inc. and Toyohashi University of Technology proposed WET for electric vehicles
13. Applications of Wireless Power Transmission
• Consumer Electronics
• Wireless charging for smartphones, tablets, and other portable devices.
• Electric Vehicles
• Wireless charging for electric vehicles, enabling convenient and cable-free
charging.
• Medical Implants
• Wireless power for medical implants, eliminating the need for invasive
surgical procedures.
• Industrial Automation
• Wireless power for robots, sensors, and other industrial equipment,
improving mobility and flexibility.