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Is there any way to calculate the ESR of electrolytic capacitors for high frequencies?

In aluminum electrolytic capacitor datasheets, the dissipation factor is given with low frequency(100Hz-120Hz) conditions, so calculation with that dissipation factor will be useless for high frequency conditions and I don't have a device to measure it.

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    \$\begingroup\$ I don't have a device to measure it don't you have a signal generator and an oscilloscope? \$\endgroup\$
    – Rohat Kılıç
    Commented May 26, 2022 at 11:20

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Is there any way to calculate the ESR of electrolytic capacitors for high frequencies?

If you need a particularly low ESR then there is little option other than to choose a capacitor whose data sheet explicitly gives you this information. For instance, the B41888 range from TDK: -

enter image description here

As with anything, you get what you pay for so, if ESR is important to your circuit then shop around for a capacitor that explicitly tells you the information unambiguously. This is what data sheets are for. Several Panasonic capacitor data sheets also specify ESR (from memory). I'm sure there will be others.

Electrolytic capacitors that don't give this invaluable information in their data sheets (or don't have links to it) are just not worth buying IMHO unless, it's not important your design.

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    \$\begingroup\$ Some manufacturers give only the impedance at 100kHz. Do they expect the designer to calculate the ESR from Z? :) \$\endgroup\$
    – Rohat Kılıç
    Commented May 26, 2022 at 11:31
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    \$\begingroup\$ @RohatKılıç they might. Take the top line above for the 330 uF capacitor. It will have a capacitive reactance of 0.0048 ohms at 100 kHz hence, if Z = 0.183 ohms at 100 kHz then ESR will be close to that value. Of course, you might have to factor in ESL (20 nH for that case size) to see how significant that was. Looks like 20 nH at 100 kHz is 0.013 ohms hence, ESR will be more like 0.182 ohms! \$\endgroup\$
    – Andy aka
    Commented May 26, 2022 at 11:37

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