# Is inductor saturation current frequency dependent?

The wiki article explaining inductor core saturation talks about magnetic domains lining up with the external magnetic field to concentrate the magnetic flux. This sounds similar to electric permittivity where dipoles rearrange themselves to cancel internal electric fields.

I know that electric permittivity is frequency dependent since the electric dipoles have inertia and cannot realign themselves instantly.

Is this the case for magnetic permeability (inductor saturation)? If an inductor is claimed to saturate at 750mA in its datasheet, would it be less if the current was AC?

• No. What frequency you used to push the core to saturation, via voltage-time area in your transformer configuration or current-inductance products in inductor configuration does not matter. You still saturate it. If you talk about inductor and DC, it's still just the peak, DC, DC+ACpeak or just ACpeak. – winny Sep 20 '17 at 15:43
• Is there anything left you need explaining or can this question and the most appropriate answer be accepted formally? – Andy aka Jan 23 '19 at 20:44

Flux density = $\mu$H where $\mu$ is the magnetic permeability of the core material and H is the applied magnetic field in units of amp-turns per metre. If the turns stay the same and the amps peak at the same value and the core doesn't magically change its dimensions then H remains constant so, providing $\mu$ remains constant, peak flux density remains constant.
However, $\mu$ will tail-off at higher frequencies and this will mean less flux density.