Spark-gap + Step-down-transformer = OU?

[nilrehob]

[broli]

Your reasoning is very good. A while ago I made a thread about a similar concept but which is mechanical.

http://www.energeticforum.com/renewable-energy/4493-create-energy-conservation-momentum-law.html

It makes sense that the flux remains constant so changing L should change I.

[nilrehob]

Yes, same thing, in my case i need to switch off the current as abrupt as possible to mimic something of an reverse elastic-collision situation.

/Hob

[sucahyo]

I think you should search Jerry Voland work too, since he obtain some interesting phenomena with spark. Unfortunately, still clue, not solution.

[nilrehob]

YouTube - MIT Physics Demo -- Adjustable Capacitor with Dielectric

/Hob

[broli]

@nilrehob: there's something we forgot. The parameter we adjust, windage, in order to change inductance has actually a squared relationship in our inductance equation and a linear one in flux. Flux isn't L*I but L*I/N. Here are some relevant equations for a straight solenoid:



That means if we for instance halve the amount of windings the current would double so flux is conserved. However our inductance will actually drop 4 times, not 2. Compensating for the increased square amperage in the energy equation.

In other words the windings do not have a linear relationship with mass. But a squared one. So this defeats our point. However there are other parameters that do have this linear relation. Area and permeability. If you can change those during operation the change would directly be reflected in an equal change of current through conservation of flux. And since they have a linear relation in both the flux and energy equation you will thus see an increase in inductive energy.

[nilrehob]

[nilrehob]

@broli

So if you have a 6-filar
put 2 winds in series, thats for input
and 4 winds in parallel, for output
might do the trick?

/Hob

[broli]

@broli

So if you have a 6-filar
put 2 winds in series, thats for input
and 4 winds in parallel, for output
might do the trick?

/Hob

The problem will persist. As you said, digest more what I said. It's a mathematical problem. When you decrease windings 2, 3 or 4 times the current will indeed rise 2, 3 and 4 times. However energy is dependent on windings squared times current squared. So mathematically you can write:



From conservation of flux we know that the product N*I remains constant. So that means energy will remain constant as well no matter the combination.

[nilrehob]

@broli

Doh!

So lets use a toroid with a ferrite core, all flux is now in the core, in the Weiss-domains of the ferrite,
now this has to work, please...

BTW, doesn't ferrite have a kind of delay for getting magnetized and demagnetized? Whats it called? If there is one wouldn't it dictate the maximum switch-off-time?

/Hob

[nilrehob]

Well, tomorrow I plan to make a toroidal transformer.
I don't have a proper or fancy core so I'm going to use a plastic-coated "garden-wire" which has some iron in it it seems.
Maybe I shall do the core as a torus instead, with the coil-wires inside?
First wind the coil-wires like an air-core coil, and then wind the garden-wire around it?

/Hob

[broli]

When you use a core you change the game, because then you start to play with permeability. Permeability change would truly change energy because it has both a linear relation with flux and energy. But the problem is that we can't instantly switch between permeabilities like we could between winding amount...or can we? For instance a ferromagnetic material losses its magnetic properties when it's heated above a point. You will gain energy through conservation of flux, the heat will go nowhere, so in theory you can extract the increased inductive energy, recapture the heat and start all over. But using heat would be terribly inefficient.

[nilrehob]

Different layers of coil-wire and garden-wire will change the permeability.
I guess the coil-part with the smaller induction H shall have the greater amount of core?
Or do I have it backwards again?

/Hob

[broli]

Different layers of coil-wire and garden-wire will change the permeability.
I guess the coil-part with the smaller induction H shall have the greater amount of core?
Or do I have it backwards again?

/Hob

Does H stand for Henry or the H field?

[nilrehob]

I meant Henry, sorry for being unspecific.

/Hob