Guru
Joined: 13/10/2014
Location: AustraliaPosts: 2039
| Posted: 12:53am 15 Jan 2023 |
Thanks poida,
I spend some more time on this and I had it hooked up exactly the same way, but I went as far as shorting the inverter V1 and V2, I wanted to see if there was a higher frequency resonance hidden in there back through the choke, but happily there was almost none, just a slight peak at around 1.2 kHz.
I just retested and the resonance has shifted up by 12 Hz? I have a bigger resonance peak as well: Different transformer, physical windings, power capability I guess play a part in that?
FYI:
130 Hz 3.5 V
100 Hz 3.9 V
90 Hz 4 V
80 Hz 3.75 V
70 Hz 2.75 V
50 Hz 1.50 V
40 Hz 1.2 V
30 Hz 1 V
I'm using just the 6 stack 45uH blue toriod choke, I'd need around 15kW to start saturating that, however there is a VERY slight 20 kHz (or whatever freq it is) switching ripple on the waveform, but changing loads now makes no difference to the wave shape at all, just a nice shaped sine wave, the idle is still 11 Watts, no audible noise under light loads, not even from the big Toriod, everything is just silent. So I'm getting comfortable enough now to think about powering it from a set of batteries and seeing how it goes with a bit more load. I think
Edited 2023-01-15 10:54 by KeepIS