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I'm looking for a way to measure core loss in RF transformers and inductors. I found a PhD thesis here:

https://vtechworks.lib.vt.edu/bitstream/handle/10919/19296/Mu_M_D_2013.pdf

which looks like just the ticket, but I'm having trouble understanding key parts. I've tried contacting the author with no success.

Chapter 3 introduces a good practical method, but I'm stumped at eqn 3.1 (pg 66).

In short, I pretty much don't get eqn 3.1 at all! If anyone can help, I would greatly appreciate it. Then perhaps eqn 3.2 will start making sense...

- Why does P
_{core}depend on capital I_{pp}and not lower-case i_{pp}? Capital I_{pp}results from the magnetizing inductance (L_{m}in fig 3.1), but lower-case i_{pp}is the current step due to core loss.- Why does P
_{core}depend on duty cycle D? Driving fig 3.1 with a rectangular wave would result in a rectangular voltage across R_{core}, so the power loss in R_{core}shouldn't depend on D at all.- Not only do I not understand why D is in there, I don't see how its use in eqn 3.1 is derived.

Gerrit

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# Understanding Core Loss Measurement

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