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It seems unintuitive to me why putting a stationary hunk or iron or neodynium in the middle of a copper coil generator would increase its conductivity, because the metal could act as its own conducting path and short paths along the copper wires and furthermore cancel out whatever opposite magnetic field is moving around it. So, why does it help?

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    \$\begingroup\$ It’s not about conductivity. Also, iron and neodymium are used for different reasons. Neodymium would be used to create a permanent magnet motor and (soft) iron is used in induction motors. Read up on motors in general, and induction in particular. \$\endgroup\$ – winny Jul 8 '18 at 8:54
  • \$\begingroup\$ Reading up is why I have this question in the first place. I understand how a simple generator works, and I can make a generator easily from scrap metals (though not very efficiently). What I don't understand is why throwing a hunk of magnetic material in the middle of the design helps with that process. \$\endgroup\$ – John Joe Jul 8 '18 at 8:58
  • \$\begingroup\$ It has to do with the magnetic field. The magnetic field passes through the iron better than it passes through the air. With your coil wrapped around the iron, more of field passes through the coil so you get more current. \$\endgroup\$ – JRE Jul 8 '18 at 9:14
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    \$\begingroup\$ Simple generator as in what type? Brushed PMDC? You need to read up on induction. \$\endgroup\$ – winny Jul 8 '18 at 9:32
  • \$\begingroup\$ The term you are looking for is "magnetic circuit". Iron forms a "low reluctance" path (like low resistance for magnetic flux). Whether that helps you or shorts out your flux paths depends on how well you design the "magnetic circuit". TL/DR you want to concentrate magnetic flux in the path which coils will pass through. \$\endgroup\$ – Brian Drummond Jul 8 '18 at 10:10
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The magnetic material doesn't increase the conductivity of the stator's coil.

The principle of any electrical machine is to use a rotating magnetic field to generate electrical coupling which allow for energy conversion. The stator's current is just a reaction to try counte-attack the induction in the stator's coil(lenz's law).

The reason why these materials are call "magnetic material" is that either they can generate a very large B field for relative small current or that their electron's spin are naturally aligned creating a noticeable B field.

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  • \$\begingroup\$ See I already knew it generated a stronger magnetic field, hence the question, you haven't explained the actual mechanism for how. Luckily, a vector analysis approach let me quickly figure it out, but I haven't seen a reputable stackexchange member actually explain it. Most of the time when I consult electrical engineers, they have no idea how to explain the "why" behind any magnetic field interaction, they reiterate whatever they were tough and nothing more and it would be nice to see if a reputable stackexchabnge member would be able to explain it so that it was more palatable to the public. \$\endgroup\$ – John Joe Jul 13 '18 at 0:07
  • \$\begingroup\$ Material will produce a lot of magnetic field if the molecular structure of the atoms allow the spins of the electrons to align themselves. It is in the realm of physics. An EE don't care about those mechanism because he only look at the global effect. To design an machine you don't need to use the principle by which magnetism is produce, you only need to know that certain material exhibit those characteristics \$\endgroup\$ – MathieuL Jul 17 '18 at 16:40
  • \$\begingroup\$ Again, I'm not disputing what allows a material to be magnetic, please don't put words in my mouth. I'm asking about how such a material is used to increase the efficiency of a generator. \$\endgroup\$ – John Joe Jul 18 '18 at 8:38

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