Lightweight air core transformer?

if it's only the turns ratio that determines how much will be the voltage increase, why don't people just make the turns on the primary just be 1?
---Emphasis added---

Succinctly, eschewal of 'all the ills' attending low impedance systems -- prominent among them being liability to core saturation and significant resistive losses (in both the primary winding and, to a greater extent, throughout the primary circuit)...

But to your broader question:
Please recall that 'turns ratio' is the sole Z-transformation determining 'factor' only where a pure (i.e. sinusoidal) signal acting 'through' a net-nonreactive system is manifest. -- As a practical matter, topologies exploitative of 'ΔI/ΔT transformation' (e.g. true flyback topologies) and/or 'resonant/periresonant transformation' (e.g. the circuit under discussion, Tesla coils, etc...) often (but not necessarily) in combination with mutual inductors marked by significant disparity in primary to secondary impedance ratios, offer --far and away-- the most efficient conversion schemes from a material (and, hence, mass) conservation standpoint...

we could spread the transformer over that entire area to increase the distance between the wires. This would also help for cooling the transformer
While your (above quoted) suggestion is both intriguing and, perhaps, practically realizable -- Please bear in mind the fact that transformer efficiency declines abruptly with reduction in primary to secondary coupling -- topologies defined by mutual (or, for that matter, self) inductance are, of course, inconstant with significant 'flux leakage' (CIP 'leakage inductance') -- That said, your proposal is definitely worthy of further investigation!:cool:

About the potting is this to prevent sparking across wires for high voltage in the closely wound wires?
Correct -- However thermal transfer is essential as well...

Best regards
HP:)
 
Last edited:
BTW, since you are a fan of Alexander Pope, here's another Pope poem for you:

March 21
Epitaph on Sir Isaac Newton
By Alexander Pope (1688–1744)
(Died March 21, 1727)
NATURE and Nature’s Laws lay hid in Night:
God said, “Let Newton be!” and all was light.
Thank you for that!:) -- By way of reciprocation I offer the following for you and innovators everywhere::cool:

"Be not the first by whom the new are tried, Nor yet the last to lay the old aside." --- Pope

Very best regards
HP:)
 

Aleph(0)

Joined Mar 14, 2015
597
why don't people just make the turns on the primary just be 1
Robert Clark There's an idea for reusing old soldering guns! Just put output from 1v, 100A 60hz supply on tip contacts and voila! 120V, 100W available on plug! But don't try to get 120kv using 1kv in or even just 1200v with 10v on input b4 you double check your fire insurance policy:D!
 

shortbus

Joined Sep 30, 2009
8,957
Thanks for that. I have a few questions: if it's only the turns ratio that determines how much will be the voltage increase, why don't people just make the turns on the primary just be 1? This would save weight and cost on the copper wire. Reducing the turns on the primary worked for your transformer to get it to the kilovolt range.
Just a total amateur but, a single primary turn would have such a low resistance that it would be like a short. Wouldn't it?

Another kind of dumb thought, maybe before doing this (lifter) the world will need to revisit Tesla's wireless delivery of electrical power. This would take the battery out of the picture.
 

cmartinez

Joined Jan 17, 2007
7,522
ust a total amateur but, a single primary turn would have such a low resistance that it would be like a short. Wouldn't it?
Yes it would. But any coil's apparent resistance (impedance) changes with frequency, as a result of its inductance. A commercial transformer, for instance, is designed to operate at 60Hz (or 50Hz, if in other countries), if you applied DC current to it, the thing would burn, as it's input would effectively be a short circuit.
 

Aleph(0)

Joined Mar 14, 2015
597
maybe before doing this (lifter) the world will need to revisit Tesla's wireless delivery of electrical power. This would take the battery out of the picture.
Shortus that's a good idea if it could be narrow tracking beam instead of spraying rf everywhere. I say HP was talking along same lines here
Alternatively, energy 'out-sourcing' may be worthy of investigation, (e.g. energy 'beamed' via ground-based maser/laser 'stations').
Now I say maser is better for purpose than laser cuz of less conversion (which means like _power detection_ ) loss and also less attenuation from atmosphere:)?
 

Aleph(0)

Joined Mar 14, 2015
597
Yes it would. But any coil's apparent resistance (impedance) changes with frequency, as a result of its inductance. A commercial transformer, for instance, is designed to operate at 60Hz (or 50Hz, if in other countries), if you applied DC current to it, the thing would burn, as it's input would effectively be a short circuit.
And also when current/turn ratio is too high, saturation starts being problem with core type inductors and resistance loss gets bad in all inductors. Even if frequency is high enough for practical primary impedance, super low primary inductance will make Q way too critical for normally varying circuit conditions.
 
And also when current/turn ratio is too high, saturation starts being problem with core type inductors and resistance loss gets bad in all inductors. Even if frequency is high enough for practical primary impedance, super low primary inductance will make Q way too critical for normally varying circuit conditions.
Why would a high turns ratio cause a problem with saturation?
 

Aleph(0)

Joined Mar 14, 2015
597
Why would a high turns ratio cause a problem with saturation?
The higher the turns ratio the higher the current in the low impedance winding (which is primary in step up configuration) so for large signal circuits (like power converter) it can saturate core when it gets too high. Now of course that applies just to active cores:)
 

Thread Starter

Robert Clark

Joined Aug 6, 2016
35
FWIW, as applied to certain areas of 'Nuclear Medicine', higher currents (and, hence, power levels) are achieved via effective placement of multiple (integral) sub-generators in parallel -- à la Wimshurst 'compounds':cool:

Best regards
HP:)

Do you have a reference for electrostatic voltage generators used in nuclear medicine?

Bob Clark
 

Aleph(0)

Joined Mar 14, 2015
597
Do you have a reference for electrostatic voltage generators used in nuclear medicine?

Bob Clark
BobClark HP is away from internet access for awhile so I found these links:cool: If they're not helpful plz ask HP when she's back on here later in week cuz she's always very pleased to help and encourage ppl with all things HV:)! One thing though, plz don't take the term _nuclear medicine_ too literally cuz it is just silly general name for branch of radiology that applies ionizing radiation (from whatever source) to therapy instead of just imaging so no isotopes⋅nuclides are necessarily necessary:D!

So here are links:
https://books.google.com/books?id=xL44oNwJsXgC&pg=PA23&lpg=PA23&dq=van+de+graph+radiology&source=bl&ots=R1OyyoocXM&sig=0iGn_-UYQ7K9K1mSJQyRxFPuHlc&hl=en&sa=X&ved=0ahUKEwjJg7va0OrOAhVFvhQKHZI_CR4Q6AEIVDAH#v=onepage&q=van de graph radiology&f=false

http://pubs.rsna.org/doi/full/10.1148/radiology.219.1.r01ap411

http://www-pub.iaea.org/MTCD/publications/PDF/P1433_CD/datasets/presentations/SM-EB-18.pdf
 

Thread Starter

Robert Clark

Joined Aug 6, 2016
35
Also, could HP tell me where I can find her lightweight transformer and a description of the necessary modifications required?

Bob Clark
 

Thread Starter

Robert Clark

Joined Aug 6, 2016
35
Nice article on using electrohydrodynamics(EHD) to improve lift for aircraft:

Flying with the Fourth State of Matter.
By Steven Ashley on Thu, 25 Aug 2016

Embedding high-voltage versions of these wind generators—flat, thin-film electrodes—in an airplane’s wings can not only summon artificial St. Elmo’s fire instantly and on command, but it can also send the charged plasma clouds—and air they carry along with them—moving in one direction or another. That is, these plasma actuators can readily accelerate, or “blow,” air where and when it’s needed with no moving parts, boosting lift or cutting drag depending on where and how they’re used.
http://www.pbs.org/wgbh/nova/next/space/plasma-air-control/

If we are successful in producing a lightweight power supply then we can use EHD itself for the propulsion.

Bob Clark
 
Last edited:

Aleph(0)

Joined Mar 14, 2015
597
Also, could HP tell me where I can find her lightweight transformer and a description of the necessary modifications required?

Bob Clark
Robert Clark it's all right here:)!
http://forum.allaboutcircuits.com/t...-and-construction.113504/page-32#post-1029914

Tutorial isn't quite done yet so you'll have to click on links to see pics. Also for your uses don't put the frame and hardware back on during reassembly just clamp the cores halves together with a strip of strapping tape that way it weights in at 280 grams or less:)! Robert Clark you can help us too by asking any questions and alerting us to any errors omissions or problems with clarity:cool:! Plz make sure to read intro cuz it explains where to find and identify correct transformers! But you can disregard part where it lists lifters among low power topics cuz she meant toy demo lifters not serious ion-craft like you're designing:)!
 
Top