Impedance of electrolytic capacitors

What is the impedance magnitude of an electrolytic capacitor?

In data sheets of electrolytic capacitors only the impedance magnitude |Z| is specified, and simply written as "Z". Regarding the IEC/EN 60384-1 standard, the impedance values of electrolytic capacitors are measured and specified at 10 kHz or 100 kHz depending on the capacitance and voltage of the capacitor.

Are there public-domain models of aluminum electrolytic capacitor impedance?

Existing public-domain models of aluminum electrolytic capacitor impedance vary from the least sophisticated, fixed series RLC, to models that add some parallel leakage compo-nents as well as temperature and frequency variation to the series resistance component.

Can aluminum electrolytic capacitors be modeled?

We have explored the issues and theory behind impedance modeling of aluminum electrolytic capacitors and have devel-oped and presented a model that has simulation and predictive value over a broad range of frequencies and temperatures, both in steady-state AC and in transient simulations.

Do electrolytic capacitors become inductive at high frequencies?

Anyone with access to an impedance meter (HP / Venable) can easily tell you that electrolytic capacitors certainly do become inductive at high frequencies. This is part of the reason why you see a lot of ceramic capacitors used in high-frequency DC-DC converters - electrolytics simply aren't that good up in the hundreds of kilohertz / megahertz.

How does frequency affect the impedance of a capacitor?

From formula (1), the amount of impedance |Z| decreases inversely with the frequency, as shown in Figure 2. In an ideal capacitor, there is no loss and the equivalent series resistance (ESR) is zero. Figure 2. Frequency characteristics of an ideal capacitor

What are the characteristics of electrolytic capacitors?

The lifetime, service life, load life or useful life of electrolytic capacitors is a special characteristic of non-solid aluminium electrolytic capacitors, whose liquid electrolyte can evaporate over time. Lowering the electrolyte level affects the electrical parameters of the capacitors.