So I ended up with another coil I could try for a choke... it's frequency is 10Khz with only tiny capacitance (none)...
So I adjusted my simulation
Updated simSim breaks though... it works pretty good ... but I dunno... if I end up flipping the switch at the wrong time it's all bad...
Plus, the secondary on a transformer only works with a CHANGING current... and sometimes when I close the switch, the current in the transformer is immediately high, and is only receding, which is the wrong direction... there should be no current (practically) because of the long time between pulses ...
Was also thinking that C28 should be lower than C+ when the coil turns on (and the choke current near zero) so it has the least impedance to charging C28...
So again, in theory, C+ should deplete, and charge C28 slightly more... but it doesn't because the inductance on the secondary is higher than the primary; so although the voltage goes up, the current goes down... so I tried reversing the ratio to 0.5x ... but then the voltage wasn't high enough to charge the cap... so I went back to 1.5
also playing with the sim, I see why he has to start the device with a lower frequency... there has to be enough time to get the choke conducting...
So if I run it so the C28 goes below C+, then it takes more power from C+ to get C28 to charge above... (loss)
if I keep C28 higher or equal to C+ so the DC current in the extra inductor stays... then the capacitive impedance is high, and it takes more work from the primary to charge C28 (loss)
Plus the diodes all require higher voltage to conduct... so there's an extra bit that is a loss
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so maybe C28 shouldn't be biased to ground? If it was biased to voltage then the voltage across that capacitor would be near 0 (both sides a X voltage of the circuit) so it should be easier to charge?
In simulation though, it's actually more difficult... I guess cause it still has to generate voltage to draw against the C+ power to charge the cap...
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played with 1:2, 2:1, 1:1, 10:1 ratios of C+ and C28... can charge 10:1 (1000uf +, 100uf 28) faster, and get the choke going better, but then there's less capacitance to charge C+ with... which is why I started to go with; well, maybe the choke has to go all the way to 0 current... which would put C28 below C+ by whatever amount C28 was charged with from L2.... divided by capacitance ratio; which would make it easier to charge initially... but then again it has to charge MORE so any extra voltage gained in C+ over what it started is used to charge C28 back up to C+ level and then some more to get it above....
I dunno; madsatbg replied that his does run for the 10 seconds he shows, but then it stops... (video ends at the point too) so another 0 for X successful replications...
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Topic: lantern4 (Read 12230 times)
