Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

skin effect

skin effect

skin effect

i am a first year electrical engenering student. In a school project i try to mesure the skin effect in a wire using à daq my plan is to get both wave forms of voltage and current then i can easely calculate the resistance using my python code as :

R = impedance* cos(phase_shift)

its seems simple but the problem that i had is after trying with multiple wire i had never been able to get a sinusoide ( i got like a periodique form but deformed) . I also tryed to filtrate but i was loosing a lot of precision . maybe my next plan will be to use a wattmeter to get the phase shift but after asking professors there is no wattmeter in our school. Can u please provide me with some suggestion to be able able like to get a sinusoide.

Best regards, .

RE: skin effect

mesure the skin effect
A different approach;
Do you have a signal generator?
Measure the impedance change of your sample at different applied frequencies.
Be aware that skin effect may also be influenced by wave shape.
Skin effect is also affected by current.
You may be able to demonstrate this by using different wave forms, rising saw tooth, falling saw tooth, sine wave.
You may be able to vary the current at given frequencies.
You may not have the equipment to pursue all of these approaches, but I am sure that you will find enough equipment to demonstrate some of them.
Note: Current dependency, as you vary the frequency be aware that if the current is not held constant, you may be looking at the combined effect of higher frequency and lower current.
Extra credit:
Try sending a frequency spectrum down you sample. See if a scope will show greater attenuation of higher frequencies.

Ohm's law
Not just a good idea;
It's the LAW!

RE: skin effect

hamid-This thread will likely disappear since student posting is not allowed per https://www.eng-tips.com/market.cfm.

waross- My understanding was that the increase in resistance from skin effect was independent of current magnitude. Calculators such as https://voltage-disturbance.com/engineering-calcul... do not include a place to enter current magnitude. Perhaps you are thinking of variable resistance in single layer ACSR conductors, where the hysteresis losses in the steel core depended on the current magnitude? I had pictured ACSR as an iron core inductor, but I have never really thought through skin effect in a ferrous material.

RE: skin effect

My understanding on Skin effect the magnitude and importance of the effect increases with the frequency, the size, shape and thickness of the conductor. It is INDEPENDENT of the magnitude of the CURRENT FLOWING.
Che Kuan Yau (Singapore)

RE: skin effect

I stand corrected. Please disregard my references to current.

Ohm's law
Not just a good idea;
It's the LAW!

RE: skin effect

This presentation of skin effect might help. This is for round conductors (solid bar and possibly pipe), The link does not provide source for the formula, you can use it as a hypothesis to be validated in your experiment.

Quote (https://www.electricaltechnology.org/2022/10/skin-...)

Skin effect increases with an increase in frequency. If the frequency is very high, the charge distribution or the current density stays maximum at the very surface and forms a thin layer while the current density at the inner cross-sectional area or the core remains zero.

Skin effects maintain the current flow between the outer surface and a fixed depth from the surface called skin depth, δ. The skin depth varies inversely with frequency.

The skin depth can be calculated using the following formula.

Skin Depth = δ = 7.6 ÷ √ (f) … (cm)

And try this search link https://duckduckgo.com/?q=skin+effect+in+transmiss...

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close