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P-hack · 01-13-2015, 04:48 PM

For some reason I'm able to get 3 of these @ 25khz to work with no red numbers 3x interleaved, 20 turns apiece, DC = %72/3. CS740060E - Sendust - Powder Cores | MH&W Direct 3 cores and 5lbs of wire. peak switch current is like 350A though average is 65A, still way too peaky for my 6mbi100 and a little fast. Though I've been watching valery wrestle with inductors for a while, so I am probably not thinking of something.

We could use an experiment though, simulating that ch200 on the edge at 300A 120uh:
@ 10khz duty cycle @%72, peak inductor current is 290A, min is 210 (~28% ripple), avg is ~250a, switch current avg=180A, peak @ 293A. Diode peak @ 295A, avg 70A. I arbitrarily put 1000uf in front and behind.

Paul, if you feel lucky with that ch-200, and have a suitable switch and diode (or halfbridge) and 300+amp 144v source, the test load is 7.2 ohms (510v/70A). Maybe something like $5 water heater elements (8 ohms total eventually, start higher) in a bucket of water for a dummy load, dunno what you have at your disposal, but there isn't a lot of room for error on the load on the low side of 7.2 ohms and if the blows open, you will be at thousands of volts in no time with a constant duty cycle applied (use an over voltage shutdown at a minimum, say 540v, overcurrent wouldn't hurt either, and it does have a bit of overshoot (740v?) if you just slam it on at %72 DC, so roll it on)... Big Dummy Load « Pro Sound Training

01-13-2015, 04:48 PM	#1585 (permalink)
P-hack Master EcoModder Join Date: Oct 2012 Location: USA Posts: 1,408 awesomer - '04 Toyota prius Thanks: 102 Thanked 252 Times in 204 Posts	For some reason I'm able to get 3 of these @ 25khz to work with no red numbers 3x interleaved, 20 turns apiece, DC = %72/3. CS740060E - Sendust - Powder Cores \| MH&W Direct 3 cores and 5lbs of wire. peak switch current is like 350A though average is 65A, still way too peaky for my 6mbi100 and a little fast. Though I've been watching valery wrestle with inductors for a while, so I am probably not thinking of something. We could use an experiment though, simulating that ch200 on the edge at 300A 120uh: @ 10khz duty cycle @%72, peak inductor current is 290A, min is 210 (~28% ripple), avg is ~250a, switch current avg=180A, peak @ 293A. Diode peak @ 295A, avg 70A. I arbitrarily put 1000uf in front and behind. Paul, if you feel lucky with that ch-200, and have a suitable switch and diode (or halfbridge) and 300+amp 144v source, the test load is 7.2 ohms (510v/70A). Maybe something like $5 water heater elements (8 ohms total eventually, start higher) in a bucket of water for a dummy load, dunno what you have at your disposal, but there isn't a lot of room for error on the load on the low side of 7.2 ohms and if the blows open, you will be at thousands of volts in no time with a constant duty cycle applied (use an over voltage shutdown at a minimum, say 540v, overcurrent wouldn't hurt either, and it does have a bit of overshoot (740v?) if you just slam it on at %72 DC, so roll it on)... Big Dummy Load « Pro Sound Training Last edited by P-hack; 01-13-2015 at 05:00 PM..