17-01-2013, 04:49 PM
Contactless energy transfer system
Contactless energy.ppt (Size: 861 KB / Downloads: 114)
Problems associated with the conventional methods
Wear and tear on electrical contacts
Exposure to environmental problems
Around 23% of transmission and distribution losses
Emergence of CEET
In 1996, Auckland Uniservices developed an Electric Bus power system using electrodynamic induction and Prof. John Boys Team commissioned 1st commercial IPT Bus in New Zealand.
Prof. Marin Solacic, at MIT, wirelessly powered a 60W light bulb with 40% efficiency at 2 meters with two 60 cm-diameter coils.
What Contactless Energy Transmission Is
Transmission of electrical energy from a power source to an electrical load without interconnecting wires
Large amount of power transmitted is received
Closely related to optimization of transferable power, efficiency and heat development
Elimination of cables, slip rings, plugs and sockets, increasing reliability
Maintenance free operation
Different Ways of Energy Transfer
Electromagnetic induction
A) Electrodynamic induction method
B) Electrostatic induction method
Electromagnetic radiation
A) Microwave method
B) Laser method
Electrical conduction
Electromagnetic Induction
Electrodynamic induction method
This wireless transmission technique is near field over distances up to about one-sixth of the wavelength used. Near field energy itself is non-radiative but some radiative losses do occur. In addition there are usually resistive losses.
Electric current flowing through a primary coil creates a magnetic field that acts on a secondary coil producing a current within it.
Inductive coupling allows power transfer from few mW up to hundred KW