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Capacitance and inductance characteristics of the capacitor

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Pixelx

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Hello
I am downloading the characteristics from a capacitor found on the desk.

Why does the inductance change depending on the frequency and have such large values? And this is the ESL of the capacitor. Unless it's some kind of mathematical abstract?
On the KEMET website I saw what such characteristics look like and it looks like they are the same, but they do not show the entire inductance characteristic, only the resonance one.
Could someone explain to me why the inductance changes here and is so large for low frequencies in the capacitor?
Is my ESR chart correct?
I determine the ESR as the real part of the impedance

The capacitor was connected as in the photo below and the VNA calibrated at the end of the cable where it connects to the socket
 

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Inductive reactance is XL=2*Pi*f*L
Therefore, reactance XL and inductance L are frequency dependent.
Causes of frequency dependence of the inductance are:
-The stray capacitance between turns in the coil become more significant at higher frequencies. This effect can decrease the inductance as frequency increase.
-The skin effect, which increases the resistance of the conductor can alter the effective inductance, especially at high frequency.
- Magnetic saturation and Eddy currents of the inductor, affect the inductance especially when the frequency increase.
 
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Pixelx said:
Hello
I am downloading the characteristics from a capacitor found on the desk.

Why does the inductance change depending on the frequency and have such large values? And this is the ESL of the capacitor. Unless it's some kind of mathematical abstract?
On the KEMET website I saw what such characteristics look like and it looks like they are the same, but they do not show the entire inductance characteristic, only the resonance one.
Could someone explain to me why the inductance changes here and is so large for low frequencies in the capacitor?
Is my ESR chart correct?
I determine the ESR as the real part of the impedance

The capacitor was connected as in the photo below and the VNA calibrated at the end of the cable where it connects to the socket
Click to expand...
Looks like you're seeing the effective series inductance (ESL) variation across frequency. At low frequencies, impedance is mostly capacitive, but as frequency increases, the inductive effects become more noticeable, leading to resonance. Beyond that point, the capacitor behaves more like an inductor. Your ESR method seems fine—real part of impedance is the way to go. Maybe check your calibration and fixture effects to ensure accuracy. What VNA are you using?
 
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The "capacitance & inductance" curve is interpreting the complex impedance of a RLC circuit as single capacitance respectively inductance. That's what a RLC meter shows, but it's not real. RLC meter measurements are almost meaningless near series resonance.
 
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This is how you can see the change in inductance from frequency, but it can't be 10^5 nH value. I don't understand this part of the characteristic that I marked in red now, where do these values come from and how to explain it physically.
It was calibrated to the end of the wire and connected after calibration to the socket visible in the photo in post 1.
I use LibreVNA so there is no way for error due to the VNA itself
 

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It's just a misinterpretation of measured complex impedance. The diagram is misleading. Component impedance is capacitive below resonance and inductive above. Red encircled curve branch is not inductive. The curve has been apparently calculated by using |X| without looking at X sign.
 
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