Post on 14-Jun-2015
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.