1

WIRELESS POWER TRANSMISSION

SUBMITTED BY-BH Abhishek Rao(ETC)Tushar Bhanarkar(ETC)

2

What is wireless power transmission(WPT)?

Why WPT? History of WPT Types of WPT

◦ Techniques to transfer energy wirelessly Advantages and disadvantages Applications Conclusion References

• OVERVIEW

3

The transmission of power from one place to another without using wires, cables or chords

But, the wireless power transmission is made possible by using various technologies like microwaves, lasers and EM waves

What is WPT?

Wireless Power Transmission 4

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%

Why not wires?

History of WPT: Tesla’s Expt

In 1899, Sir Nikola Tesla Proposed a method of Wireless Power Transmission.

As it is in Radiative mode, most of the Power was wasted and has less efficiency.

The efficient midrange power transfer concept is Witricity. In this model source and load are in Magnetic resonance so there is no power loss.

6

CONCEPT OF ELECTROMAGNETIC WAVE:

When an electric current passes through a wire, there is an electric field & magnetic field in the dielectric surrounding the conductor .

The electric field of a circuit over which energy flows has three main axes which are mutually perpendicular to each other:a. The magnetic field, concentric with the conductor.b. The lines of electric force, radial to the conductor.c. The power gradient, parallel to the conductor.

RESONANCE COUPLING

A group of theoretical physicists at MIT came up with the idea to use resonant induction to transmit power wirelessly led by Dr. Marin Soljacic.

“Resonance", a phenomenon that causes an object to vibrate when energy of a certain frequency is applied.

The Rise Of The Fallen in 2007

8

9

ReliableEfficientFastLow maintenance costCan be used for short-range or long-range.

Why WPT?

04/11/2023Wireless Power Transmission 10

11

The transfer of energy◦ Magnetic coupling◦ Inductive coupling

Simplest Wireless Energy coupling is a transformer

Energy Coupling

12

13

Electricity

Magnetism

Electromagnetism

Magnetic Induction

Energy/Power Coupling

Resonance

Resonant Magnetic Coupling

14

Inductive Coupling:

It uses magnetic fields that is produced due to current's movement through wire. Bending the wire into a coil amplifies the magnetic field. The more loops the coil makes, the bigger the field will be. This is the principle how a transformer works.Using it an electric toothbrush recharged. It takes three basic steps:1. Current from the wall outlet flows through a coil inside the charger,

creating a magnetic field. In a transformer, this coil is called the primary winding.

2. When you place your toothbrush in the charger, the magnetic field induces a current in another coil, or secondary winding, which connects to the battery.

3. This current recharges the battery.

15

Need of Resonant coupling:

Non-resonant coupled inductors(transformers,)work on the principle of inductive coupling is of short range power transfer & requires a magnetic core. Over greater distances the NRI Method is highly inefficient and wastes the majority of the energy in resistive losses of the primary coil.Hence concept of resonant coupling comes where two coils are tuned to a particular frequency called resonating frequency & absorb optimal energy.

04/11/2023Wireless Power Transmission 16

04/11/2023Wireless Power Transmission 17

04/11/2023Wireless Power Transmission 18

Comparison with other technologies:

In conventional transformers, for inductive transfer efficiency around 80% at short range in witricity tightly coupled conventional transformers has efficiency around 90-95% .In addition, where batteries need periodic maintenance and replacement, resonant energy transfer can be used instead. So pollution due to Batteries during their construction and their disposal is largely avoided.

WITRICITY CONCERNS

Will it harm me? Will it harm the environment? Will it interfere with important communication?

NO

20

No wires No e-waste Need for battery is

eliminated Efficient energy

transfer Harmless, if field

strengths under safety levels

Maintenance cost is less

Advantages of WPT

21

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

Disadvantages

22

Applications

23

24

25

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

Wireless Power Transmission

Conclusion

26

“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”

Wikipedia. EFY posted articles on WPT.

References

27Wireless Power Transmission

Thank You.