I want to have another go at this. This is not my field so I if I get way off on something basic perhaps someone with experience will correct me rather than my leave my butt out in the wind. So in considering the use of Litz wire in a monopole machine I see two parameters. First is the electromagnet strength, which will determine the torque and rpms of the machine and second is the inductive/radiant spike, which is the primary energy output of the machine. Looking at the first point, errr first, electromagnet strength is a function of core material (permeability, saturation point) and amp turns. Maybe more, but I think those are, conventionally speaking, the main things. Leaving aside core material, looking at amp turns, one can put an increasing number of winds(turns) on a core and get increasing magnet strength. However as this process continues two factors come into play. One is that the increasing turns remove the wire further and further from the core (ooh ... this honestly just occurred to me, how well does magnetic strength "conduct" down a core? i.e. if you have a one foot long 1/4 inch diameter core with 500 winds right up against the core what is its strength compared with a one inch long 1/4 core with 12 layers?). Along with the wire getting progressively further from the core, the increasing length of wire also adds more and more resistance. At first this is negligible, however at some point there is a maximum to magnetic strength and the increased winds lead to a decrease in amps per turn such that magnetic strength declines. It could be noted that the decrease in magnetic strength may not parallel the decrease in amps. That is to say, it is my understanding that (because of the increasing turns - though at reduced amperage) even with a weaker electromagnet one's efficiency in terms of magnet strength/amps input may still increase for a time with increasing turns. Considering Litz wire in this situation (ignoring inter turn effects because I have no ideaer though would be happy to learn), if one replaces a 1000 turns of say 23 gauge wire with 10 sets of one hundred turns of (what ever when combined together would equal 23 gauge) I'll guess 30 gauge wire what do we get? Well, alright I should really do all the math in terms of resistance per length, wire diameter and how many turns can fit with circular geometry ... nah. Consider a wire with a one inch diameter. Now slice it like a pie through the center into ten slices. This wire is very long and now is wound into an electromagnet. I have to think if you run a current through the whole wire or all the wire in separate pieces (litz wire) you are going to get the same result. I conclude that litz wire (again I know nothing of inter wire effects, as Sgt Schultz said I see nothing ... nothing!) has no effect on magnet strength unless one is dealing with a skin effect. Skin effect is spoken about in terms of high frequency AC current but I would guess?? it occurs also with high frequency pulsed DC. In this case, considering skin effect, if your one inch diameter wire lost ten percent of its diameter from skin effect this means the ten segmented wires of one tenth the size will no longer conduct at all. Wait ... that doesn't work, what if they each lost ten percent? that doesn't work either. While I have no idea how or why, Litz wire is protective against skin effect. Given this, one can have an electromagnet strength when pulsed that is close to equivalent to what one gets when simply running a DC current into the electromagnet, ain't life grand?
Moving on, what about the radiant spike? The radiant spike, in my view will be a function of the magnetic flux across the conductive coil occurring from the collapse of the electromagnet. So for some reason that I can't explain I acknowledge that Litz wire is "protective" against skin effect changes with rapidly pulsed DC. However something queer, yes queer, also comes into play when considering the radiant/inductive spike. It doesn't give a darn about wire diameter. I've heard JB has demonstrated this, I've read the Russians, yes ... okay no, a Russian researcher transmitted kilowatts of power through a single hair thin wire. When radiant, the power doesn't care much about wire diameter.
So, and pardon me that I am thinking this through a bit as I write, let's go back to Litz wire and the inductive spike. The pulse is stronger because the Litz wire is "protective" against skin effect. However, the inductive pulse doesn't care about the decreased wire diameter. So ... if you used eight wires litzed you wouldn't have to worry about pulse hertz and would get the maximum inductive spike from the Litz wires.
Could be way off on all this, as I said why the heck does Litz wire mitigate skin effect, I would think it would compound it. In any event I had a naughty thought when starting this post. Should probably just leave it there ... but I'll continue. There's maybe nothing to this, as I said it just occurred to me. A Russian researcher has demonstrated the transmission of let's say 1 kilowatt of power, as one wire transmission, through a hair thin wire. Da, da, it has to be pulsed DC power, yet nonetheless, what happens if you wind that hair thin low resistance wire into a coil?
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Originally Posted by Cadman
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