Reduction of eddy currents' magnetic field during induction

AI Thread Summary
The discussion focuses on reducing eddy currents' magnetic field during induction, particularly in the context of using a laminated magnetic core, which is typically placed in transformers with windings around it. Participants clarify that commercially available permanent magnets are artificially magnetized, and the effectiveness of natural magnets is debated regarding their retentivity. Eddy currents are less of a concern unless the core allows alternating magnetic flux, such as in electric motors or transformers, where low retentivity is preferred. For a linear generator setup, minimizing eddy currents involves arranging the magnetic field to prevent recirculating currents, while considerations for cooling methods and energy losses are also raised. Overall, the conversation emphasizes the importance of understanding magnetic properties and configurations to optimize performance.
adeborts
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Since the field in the title is opposing the original magnetic flux that causes the induction, how can it be reduced?
I understand that a laminated magnetic core can be used.
1) Where is this magnetic laminated core placed?
2) Can it be obtained from specialized manufacturers?
3) My choice for the permanent magnet is the natural kind. Would this be the best choice, given that artificially magnetized materials lose their strength in time?

Sorry for the awkward, all-over-the-place manner in which I post the questions.
I am ignorant and eager.

I appreciate, beforehand, the knowledge and patience of all respondents.
 
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adeborts said:
) Where is this magnetic laminated core placed?
Sounds like you are talking about a transformer. The windings are wound on the core.
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adeborts said:
My choice for the permanent magnet is the natural kind.
Could you elaborate?
 
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All commercially available permanent magnets are artificially magnetized. Reducing eddy current is unimportant unless the core permits alternating magnetic flux (such as electric motor armature, antenna core, or transformer). You want the retentivity of the ferromagnetic core to be as low as possible in those cases.

In a permanent magnet, it's the opposite. The greater the retentivity, the better.
 
Many thanks to both!

Here is what's going on:

I have access to a primary source of energy which I would use to maintain the motion of a translator in a linear generator.
In my mind, the translator would be a natural permanent magnet.
- What are the losses due to the eddy currents during the process?
How do I minimize those?
- What about the heating?
What is the best cooling method?
- Any other caveats?

Thanks.
 
If you're talking about a homopolar generator, the conventional way to reduce eddy current is to arrange the magnetic field so that it doesn't induce current that recirculates.
 
David Lewis said:
If you're talking about a homopolar generator, the conventional way to reduce eddy current is to arrange thye magnetic field so that it doesn't induce current that recirculates.

Thank you.
 
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