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Old 01-11-2015, 09:09 PM   #1562 (permalink)
cts_casemod
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Quote:
Originally Posted by P-hack View Post
2 of the ES55242-140M-200AV might work interleaved @ 20khz per inductor to make 70A@510v combined from 144v, not real sure how to compute inductor losses though. Just resistive would be about 12watts apiece, 215 peak inductor current, avg ~107 (triangular). 1.1mOhm.

reduce the duty cycle or the load or the frequency and it gets discontinuous (though the inductor is ramping from ~0-215A as it is). Though I realize I'm proposing %100 current ripple here, so gonna be some AC losses...
Ive been doing some calculations using the micrometals simulator.

http://www.micrometals.com/downloads..._March2010.exe

Ripple translates to very high core losses. They go down with frequency (100KHz++). To reduce them one could increase the inductance, but that would increase copper losses. Add to that that the inductance itself goes down very quickly at high currents and this might be a harder challenge than originally envisioned.
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