WIRELESS POWER TRANSMISSION

BY, DHANSHA THAKUR

ANIRUDH K.N GEETHU KRISHNAKUMAR

JITHU NAIR

INTRODUCTION

• Wireless power transfer can make electronic devices like cell phones, household robots, mp3 players, laptop computers and other portable electronics wire-free.

• Resonant inductive coupling which is one of the various power transmission techniques is demonstrated here.

ABSTRACT

• Many researchers have developed several techniques for moving electricity over long distances without wires.

• Witricity is based upon coupled resonant objects.• Two objects having same resonating frequency

and in magnetic resonance tend to exchange energy, while dissipating relatively little energy to the extraneous off-resonant objects.

RESONANT INDUCTIVE COUPLING

• Inductive charging uses an electromagnetic field to transfer energy between two objects.

• Greater distances can be achieved by using resonant inductive coupling.

• Resonant inductive coupling or electrodynamic induction is the near field wireless transmission between two coils that are tuned to resonate at the same frequency.

RESONANT INDUCTIVE COUPLING

• 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.

RESONANT INDUCTIVE COUPLING

• Resonant transfer works by making a coil ring with an oscillating current.

• This generates an oscillating magnetic field.

• Because the coil is highly resonant any energy placed in the coil dies away relatively slowly over very many cycles.

• But if a second coil is brought near it, the coil can pick up most of the energy before it is lost, even if it is some distance away.

BLOCK DIAGRAM

BLOCK DIAGRAM

• Oscillator used is an astable multivibrator using 555timer which switches IRFP250 to produce oscillations in the primary coil.

• Secondary coil kept at a distance resonates at the same frequency and power transfer takes place.

• Signal received in the secondary is rectified and regulated.

CIRCUIT DIAGRAM

PRIMARY CIRCUIT

PRIMARY CIRCUIT

• Oscillator is an astable multivibrator using 555 timer a rectangular-wave generating circuit.

• A pot connected between the 6 and 7 terminals of the timer is adjusted to tune the primary and secondary coils at the same resonating frequency.

• The astable multivibrator causes an IRFP250 transistor to undergo switching to produce oscillations of required strength.

• A primary coil made of 8 turns of a magnetic wire is connected to IRFP250

SECONDARY CIRCUIT

SECONDARY CIRCUIT

• A coil of same dimensions as that of the primary is connected in the secondary circuit.

• An MKP capacitor of 1 is connected to the coil to form an oscillating tank circuit.

• An LED can be glown even using AC before using the rectifier stage.

• AC voltage is rectified using a UF4007 fast rectifierand smoothened using a filter capacitor.

PRIMARY PCB LAYOUT

PRIMARY COMPONENT LAYOUT

SECONDARY PCB LAYOUT

SECONDARY COMPONENT LAYOUT

APPLICATIONS

• Provides charging stations for handheld devices like phones ex:powermat, removes the need for multiple power sockets

• Can operate appliances like tv • Electric car manufacturers consider it for

charging electric cars, currently using wires for this purpose is not entirely practical

ADVANTAGES

• Non-radiative energy transfer is safe for people and animals.

• Wastage of power is less.• Highly resonant strong coupling provides high

efficiency over distance.• Does not interfere with radio waves.

CONCLUSION

• Wireless power transfer is quickly becoming a viable reality.

• This technology offers an extremely efficient alternative to previous attempts at providing wireless power.

• Future improvements in wireless technology offer world changing implications.