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wireless 'power' transfer?

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Steve Conner

Tue Mar 07 2006, 02:01PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

I don't think the Fres's really matter that much. Even if the primary and the two secondaries all had exactly the same Fres, as soon as the three coils were coupled together, the system would have three different resonant frequencies- that's what the maths predicts.

Marko

Tue Mar 07 2006, 02:25PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

I don't think the Fres's really matter that much. Even if the primary and the two secondaries all had exactly the same Fres, as soon as the three coils were coupled together, the system would have three different resonant frequencies- that's what the maths predicts.

For transfer itself exact resonance is top priority - just compare my coils with blackplasma's - big difference.
Main circuit is just two LC's coupled with small capacitance (between topoads) and ground.
When resonator is resonant it acts as zero impedance to TC and drops its Q directly (also checked) drawing current limited by capacitive impedance, C is very small but frequency high so small current cna pass.
With enough current resonator will (only at its Fres) build up high voltage if losses are not too high.

So can you explain a bit that about 3 different frequencies

Or you just tought about breakouts?

Steve Conner

Tue Mar 07 2006, 04:08PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Richie Burnett explains on his site how coupling two resonators causes "frequency splitting"-

If you couple three resonators, the theory is the same, except you get three split frequencies rather than two. My twin DRSSTC had three resonators: one primary tank circuit and two secondaries.

HV Enthusiast

Tue Mar 07 2006, 06:38PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
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Posts: 3068

Frequency splitting occurs because in a coupled system, the more the system is coupled, the more capacitance each side "sees" of the other. In a dual coil system, this creates the classic double-hump response.

Avalanche

Tue Mar 07 2006, 06:58PM

Registered Member #103 Joined: Thu Feb 09 2006, 08:16PM
Location: Derby, UK
Posts: 845

I've sucessfully transferred power from my small 1Mhz coil (without breakout, and a ball bearing topload) to an insulated aluminium plate. A light bulb in series with the plate and ground will light up brightly a few inches away, so the reciever doesn't have to be tuned in this case. It's just capacitive coupling between the coil and the insulated plate. Tesla has a patent for this, and it's where I got the idea - 'method for utilisation of radiant energy'. In his system he is charging a capacitor and discharging it at intervals, but I haven't managed to make it charge a cap yet....

I am currently working on some equipment for measuring the efficiency of the transfer - but I haven't touched it for a long time!

HV Enthusiast

Tue Mar 07 2006, 07:32PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

wrote ...

TCs and probably magnifiers even better can be used to transmit usable amounts of power over distances.

In all fairness to Mr. Nikola Tesla, he was trying to transmit enormous amounts of power wirelessly over thousands of miles, not a few feet in a laboratory. Its a huge stretch of the imagination to be able to say that TCs and magnifiers can transmit "usable" power wirelessly over distances by your experiment alone.

Marko

Tue Mar 07 2006, 08:03PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Well distances for me (obivously) means tens of centimeters (not miles)

You didnt notice that's the funny part of post

And sory about bothering about frequency split, you confused me at first.

Maybe wanted to use ionosphere as conductor, some earth resonances or etc. to drasticaly improve the transfer that could in basis only be capacitive coupling method, but that's off the topic (and maybe even forum).

I've sucessfully transferred power from my small 1Mhz coil (without breakout, and a ball bearing topload) to an insulated aluminium plate. A light bulb in series with the plate and ground will light up brightly a few inches away

Plate to ground must be very close to coil in order to receive some amount of power, as bulb shows high impedance compared to grounding around, so i doubt its some huge efficiency (mine is, lol, also about 10 -20%

so dont care)

cheers

Hazmatt_(The Underdog)

Tue Mar 07 2006, 08:22PM

Registered Member #135 Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735

My power input is about 750-800W, I would know for sure, but I haven't hooked up my wattmeter to my system yet.

My 'sympathetic' or external resonator to the system was about 3' away from the topload with its wire pointing in the air. I think at best I had some 4" arcs coming off of it, but I had no ground plane near that wire, so my best guess is I may have had 5" arcs to ground target.

I just wanted to make sure that it was known that my arcs were freestanding and not encouraged or drawn off by a grounded target.

Marko

Tue Mar 07 2006, 08:44PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Nice, hazmatt, if you can drav inches long arcs you can draw out a lot of power resonator, even when its so far that it doesnt throw any sparks at all.
You can maybe try few windings + bulb as I did

ALso you can try ground shield on TC (dont know how would it help in SGTC) and of course don't let any streamers from it for maximum e field.

Anyway when scaled down its far better than my experiment, good job.

teravolt

Tue Mar 07 2006, 08:49PM

Registered Member #195 Joined: Fri Feb 17 2006, 08:27PM
Location: Berkeley, ca.
Posts: 1111

It has been my experience that placeing a secondary coil next to an active tasla generates its own sparks. Tesla did this at colarado springs.

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