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an inductor working around 2 KHz of 160uH design

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billano786

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Q factor

I want to design an inductor working around 2 KHz of 160uH. Going by exprience of you peolple what is the maximum value of Q factor that can be obtained practically?
 

flatulent

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few hundred

You can get a few hundred if you use a large pot core and a bobin with three sections to keep the self capacitance down.

the Ferroxcube web site has a pdf manual on making inductors and other magnetic parts.
 

bappa_banga

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does anyone have materials on how to calculate the q factor
 

flatulent

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core losses

The problem with inductors that use coils is the core loss. I do not know of any algebraic formulas for doing this with specific core material.
 

billano786

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Has any one personally ever achieved Q about 100 at 3A current (3kHZ) using pot core?
 

pool_77

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next week, I will be probably measure on Q meter. I can try to measure similar coil which I found and I will inform you about

pool_77
 

flatulent

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pot cores

The Q should be large with a gapped core which reduces core loss. This cannot be gone to extremes as the very large gap requires more wire turns which raises the resistance loss.
 

pool_77

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Yes, you are right,
because there is a big current, there must be a gap. I think that it is possible to use core with diam. about 26 mm or less, gap about 0.4 mm and Al since 250nH, DC resistance about 1 ohm with wire about 0,7 mm.


pool_77
 

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gapped cores

There are several other areas to use gapped cores.

One is for large AC signals like in HF transmitters. The currents they produce will saturate not-gapped cores.

Another is precision inductors and high Q inductors.

One assembly trick for all cores is to remove the small flakes of ferrite from the mating surfaces which cause unwanted air gaps. This is done by wiping the mating surfaces on a piece of paper seconds before putting the core halves together.
 

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