# Correctly Using the Chan model in LTSpice

I am trying to use the Chan model to better simulate a transformer in my design. When I am making an equivalent transformer circuit, where does the Chan inductor go?

On the LTWiki it is implied that inductors based on core properties go on the center 'node' of the expanded transformer, but other sources say it should go across any one of the windings.

My next question is, wherever it does go, does it model both hysteresis AND eddy currents or do I need a parallel resistor as well for correct modeling?

Finally, is the N parameter the total number of windings of the transformer(what the core would see), the number of turns of the specific winding the Chan core is across, or just N = 1?

I have tried looking through the manual and the Yahoo group but if anyone has any experience with the Chan core I would appreciate any advice.

• See if this doesn't answer your question. Mar 11 '19 at 17:32
• It answers the placement and turns questions, but in your experience DOES the Chan core model eddy current losses? I've only seen it mention hysteresis effects. Mar 11 '19 at 18:34
• No, it doesn't. Unless you know of a different way, the usual parallel resistor is the only fix, as you mention. Don't forget that, if you're using it across the Chan core, the number of turns is unity (as per the linked answer), so adapt accordingly. For enhanced behaviour, you can simply specify Rpar. Mar 11 '19 at 19:06
• Thank you. One last question - I'm trying to fit the BH curves and core losses to the material datasheet with just this chan core and a parallel resistor. Should I be using the total current through both for Hc, etc calculations or just through the chan inductor? Mar 13 '19 at 19:14
• The Chan core is meant to be standalone, whatever parallel resistor you add is just that, an addition, so Hc refers only for the Chan core, in the same way the datasheet for a ferrite core will specify Hc for itself, not for the losses. Mar 14 '19 at 15:23