Guru
Joined: 21/06/2018
Location: AustraliaPosts: 1191
| Posted: 03:48pm 09 Jun 2024 |
Dex after a lot more thought & calculations I am going to make a prediction that the plate may make a little difference but I suspect not nearly, enough so it is unlikely to fix the problems that we are seeing. I calculated your turns ration as about 1:8.55 what is the real ratio?
There is something going on here that I cannot explain - yet. The fact that with the output at 214V the input was down to 53.3V from 53.6V, the % was down to 71.6 from 72.4 I calculated that the output voltage should be only down by about 4.1V to 226.4 not what we are seeing 214 ie down 16V.
I agree with your comment that if it was significant noise in the feedback signal we should see the % drop further than what we see.
The paradox is that we have a servo system. If the output droops, the drive % increases, if the output climbs, the % drive reduces. Yet we are seeing the output droop fairly significantly and the servo loop % change we should see is ~1.8% change but we see ~7.17%.
I suggest tests are carried out as below just one at a time then re-test the droop.
1) What is the load we are looking at in the above pictures you posted, is it purely resistive ? If not try a resistive load as Phil suggested and re-test.
2)Could you also remove the AC feedback wires from the clip on ferrite suppressors and retest. (leave them off for now)
3) Could you please remove the ground connection marked in a triangle with ! on it ie the node of the transformer leg and the mains filter leg and retest. (leave it off for now).
4) Oh damn we got to 4)...can you please ask anyone else here if they can make sense of what is going on ?
5) Is the software % readout figure lying to us? Is it possible the AC voltage feedback wires to the controller are actually coming from the input to the mains filter not the output (ie right at the transformer) - small wiring error?
I'm calling it a night Dex hope you get somewhere and I see a happy post in the morning. What you are seeing is not normal. Maybe a few more pictures of the inverter construction from a few different angles might help too?
Edited 2024-06-10 01:54 by wiseguy