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Old 01-07-2015, 01:40 PM   #1531 (permalink)
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Originally Posted by P-hack View Post
re: is 600 amps needed, yes, because it behaves much like a transformer, to get 288vdc @ 300 amps out, you need ~144vdc @ 600 amps in.

I goofed though, and used 60 amps in that example, fixed:/

Anyway, to keep the inductor the same (40uh) at 20khz, you can reduce the ripple by 1/2 to %15, or you can reduce the current by 1/2 (300A).
The peak inductor current would effectively be 600A (50% duty) but the average current would be about 300A. and even that would only be sustained for a few seconds. So I don't think for a traction application there's a need for an inductor rated at 600 continuous amps, as long as the core does not saturate.

Also by your calculations the required inductance at 20KHz is half, so its possible to use 2 wires in parallel doubling the current capability. (Again, smaller core)

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