Levitation of a coil

A coil being levitated above a copper plate by eddy current repulsion

Eddy current repulsion can provide enough force to give levitation of a coil. The coil was out of a defibrillator output circuit. Don’t know number of turns but the inductance is 10 mH (I think). It is drawing 6.5 A at 100 V AC to get the lift of about 1/2 inch off a 1/4 inch copper plate. It is tethered like a conventional lifter. The power is over 600 W so gets hot quickly.
“Continue reading” for further examples and calculations. 5 photos and links….

Levitation of a coil plus added weightThe 284 g coil lifting a 217 g solder reel (total 500 g). Current at 6.5 A was a bit higher and distance off the base was 1/4 inch compared with 1/2 inch before.

Levitating coil voltage 100 V ACLevitating coil current 6.64 ALevitating coil at  true RMS power of 0.55 kW (550 W) Above, left photo shows voltage across coil of 100.6 V, middle photo shows current of 6.61 A (giving 665 VA) and the right photo shows true RMS power of 0.55 kW (550 W). I presume this is a power factor of 0.82.
Hence, levitation of a coil plus load takes around 550 W for a total weight of 500g. This equates to around 1 kW/kg.
Levitation of a typical person by this method should take 100 kW if the weight of the coil is taken into account. Don’t take the wheels off your skateboard yet.

Levitation of a double coilLevitation of two coil Above, left photo shows double coils elevating with only the two power feed wires for directional support wires.  The true RMS power is 1.3 kW.

Note that there is no effect of a large iron mass beneath it.  This is a demonstration of the skin depth of copper of about 5 mm at 50 Hz.

I did try levitating a MOT with the E section opened and facing down but really needed a better winding. Hence I tried a non cored coil.

Related pages

Alternating magnetic induce an eddy current and an opposing force.   Levitation by induction

Try something else

Bye, bye bunny   Exploding Easter Bunny

External links

Electromagnet – Wikipedia

Photo Date: May 21, 2006

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