Wireless power transfer, wireless power transmission, wireless energy transmission, or electromagnetic power transfer is the transmission of electrical energy without wires as a physical link.

1. DEPARTMENT OF ELECTRONIC AND
COMMUNICATION ENGINEERING
WIRELESS POWER TRANSMISSION
Name:- MOHD MOHSIN
Roll No:- 1609731055
Year:- 2020

2. CONTENT
 Introduction
 Why is WPT?
 History of WPT
 Types of WPT
 Techniques to transfer energy wirelessly
 Advantages and disadvantages
 Applications
 Conclusion
 References

3. INTRODUCTION
 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
 As per studies, most electrical energy transfer is through wires. Most of the energy loss is
during transmission
 On an average, more than 30%
 In India, it exceeds 40%

4. Why WPT ?
 Reliable
 Efficient
 Fast
 Low maintenance cost
 Can be used for short-range or long range.

5. History
 Nikola Tesla in late 1890s
 His vision for “World Wireless System”
 The 187 feet tall tower to broadcast energy
 All people can have access to free energy Shortage
of fund lead to nonoperation He used to lamp 200
lights from 40 km distance
Fig.1Tesla Wardencyffe project achive [1]

6. 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

7. Energy coupling
 The transfer of energy
 Magnetic coupling
 Inductive coupling
 Simplest Wireless Energy coupling is a transformer
Fig.2 Transformer [2]

8. Inductive coupling
 Primary and secondary coils are not connected with wires.
 Energy transfer is due to Mutual Induction Wireless
 Charging Pad(WCP) ,Electric Brushes are some examples.
Fig.3 Inductive coupling [3]

9. Resonance inductive coupling (RIC)
 The capacitor and inductor forms the resonator. Charge oscillates between
inductor (as magnetic field) and capacitor (as electric field)
 This type of oscillation is called resonance if the reactance's
of the inductor and capacitor are equal
Fig.4 Block diagram of RIC [4]

10. 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 negligeibe

11. 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
Fig.5 Air Ionization [6]

12. Microwave Power Transfer(MPT)
 Transfers high power from one place to another. Two places being in line of sight
usually
 Electrical energy to microwave energy
 Capturing microwaves using rectenna
 Microwave energy to electrical 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

13. 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

14. 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
 Each SPS may have 400 million photocells
 Efficiency exceeds 95%, if microwave is used

15. Advantages
 No wires
 No Energy-waste as compared to dumped used batteries
 Need for battery is eliminated
 Maintenance cost is less

16. Disadvantages
 Initial cost is high
 In RIC, tuning is difficult(L & C Values for Resonance)
 Air ionization technique is not feasible( small distance, High voltage, )
 Distance constraint

17. The Qi Standard
 Qi(Chee) is a interface standard Developed by Wireless Power
Consortium
 It works for a distance up to 40mm(1.6inches)
 Comprises a transmission
 pad & a compatible receive

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. References
 Wireless Power Transmission”, Vol No.-45, Electronics For U –August-
2013
 Peter Vaessen,” Wireless Power Transmission”, Leonardo Energy,
September 2009
 C.C. Leung, T.P. Chan, K.C. Lit, K.W. Tam and Lee Yi Chow, “Wireless
Power Transmission and Charging Pad”
 White Paper on Solar Power Satellite (SPS) Systems, URSI, September
2006
 Richard M. Dickinson, and Jerry Grey, “Lasers for Wireless Power
Transmission” David Schneider, “Electrons unplugged”, IEEE Spectrum,
May 2010

21. References(cont.)
 André Kurs, Aristeidis Karalis, Robert Moffatt, J. D. Joannopoulos, Peter
Fisher and Marin Soljačić, “Wireless Power Transfer via Strongly Coupled
Magnetic Resonances”, Science, June 2007
 T. R. Robinson, T. K. Yeoman and R. S. Dhillon, “Environmental impact of
high power density microwave beams on different atmospheric layers”,
 White Paper on Solar Power Satellite (SPS) Systems, URSI, September
2006
 Richard M. Dickinson, and Jerry Grey, “Lasers for Wireless Power
Transmission”
 S.S. Ahmed, T.W. Yeong and H.B. Ahmad, “Wireless power transmission
and its annexure to the grid system”

22. References(cont.)
 S. Sheik Mohammed, K. Ramasamy, T. Shanmuganantham,” Wireless power
transmission – a next generation power transmission system”, International
Journal of Computer Applications (0975 – 8887) (Volume 1 – No. 13)
 Peter Vaessen,” Wireless Power Transmission”, Leonardo Energy, September
2009
 C.C. Leung, T.P. Chan, K.C. Lit, K.W. Tam and Lee Yi Chow, “Wireless Power
Transmission and Charging Pad”
 David Schneider, “Electrons unplugged”, IEEE Spectrum, May 2010
 Shahrzad Jalali Mazlouman, Alireza Mahanfar, Bozena Kaminska, “Mid-range
Wireless Energy Transfer Using Inductive Resonance for Wireless Sensors”

23. THANK YOU!