Magnet charger. 1

[JayDub]

I am interested in building a magnet charging device for saturating magnets in DC motor assemblies. TDK lists the residual flux densities if this particular magnet series wet-anisotropic(SrO6Fe2O3) @ 4.6kG. It is my understanding that a field in excess of 5x this is neccessary to fully saturate these magnets.
Firstly, is this actually the case? Secondly, is there a way to calculate the Gauss or Tesla produced by electro magnetic coil if I know how many amp turns the coil produces? Conversely, how do I calculate the size of the coils (and power)neccessary to produce A field of this size?

 

[EdStainless]

Yes.
Yes.
Now you are getting picky.
I take it that this is a multi-pole assembly. Most of these jobs are done with air-core pulse magetizers. You need to reach fields beyond the saturation of iron and you want to do it quickly.
When we know what the geometry is we can discuss this further.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[JayDub]

Geometry of the permanent magnet assembly I assume? I also assume air-core because I need to reach 2.3 tesla or higher, and most steel/iron will saturate at 1.6 or so(?). Thanks for the response by the way.

 

[EdStainless]

You have it now. A simple 2 or 4 pole config is easy, going beyond that gets tricky. Of course it also depends on weather this is production tooling or just for some tests.
The capacitor discharge equipment for driving it is fairly simple too. Just one caution, if the coils have few turns the pulse might be too short. Better to use lower power and a few more turns.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[JayDub]

I had imagined the assembly would be 2 pole, and the unit would be built for testing, so there would be no issue with production cycles.
However, with a air-core type of unit how do I interface the magnet/can assembly to the coils (and what materials to use)? Also what would be the ideal materials to wrap the coils around (fiberglass/composite tubing?)
I live in the silicon valley, so there are plenty of good tech surplus outlets, and just about anything is available.

 

[EdStainless]

Since it won't be production you don't need water cooling. Use some fiber glass/epoxy tube to wrap teh windings around. Square magnet wire wraps nice, but round will work. Regular varnished wire is fine, say #10 or so.
You will also need to build a frame or box to hold you coils. I alwaysed like using paper/phenolic plates since they are easy to work with.
You are basicly builing a simple solinoid with a window in it.


= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[JayDub]

Well, I built a quick cad model of what I think the core should look like. If it appears as though it will work, then I can go ahead and start building it. Thanks again.