Guru
Joined: 21/06/2018
Location: AustraliaPosts: 1204
| Posted: 11:01am 30 Dec 2022 |
Mike I agree that my build and its trials and tribulations are a bit hard to follow as I have not presented it as a finished project as its still a work in progress. The most recent encouraging discovery is that I unwound a couple of turns from my choke in series with the Toroid to see what would happen and the grunt was about 1/3 of its previous volume.
I also noticed the idling current went up a little bit - from memory ~ 15% but it was still very respectable - I don't have the figures with me I'll guess from ~11.5W to ~13W. I wanted to investigate this further but need to get at my bench, I am currently having "quality" family time on holidays......dreaming about the workbench and stuff I was dragged away from and am missing
As my situation & need is a bit different to others here, my need for an inverter has taken a bit of a back step. The Tektronix current probe amplifier I had, was always difficult to work with as the calibration shifted with different range/sensitivity levels and was a pain in the proverbial, so I spat the dummy and dismantled it enough to find one of the printed Laser trimmed ceramic precision X2 50ohm multi switching attenuator networks, which is a "T" resistor setup and the one to earth was open circuit. So I ordered another amplifier unit for "parts" only, so I could repair my unit. This has taken nearly ~ 3 months total to finally have my amp working & calibrated perfectly. Some helpful sod had also tweaked some of the internal settings in an attempt to fix it, which all needed to be reverted.
I am telling you this tale of woe as I got to the stage of wanting to do a bit of an in- depth investigation of the inverter transformer's choke to try to get the best "goldilocks" solution and needed a reliable current probe to see what was really going on. I was encouraged that just taking a few turns off my choke had made such an improvement. I believe the final success of my inverter rests with the correct choke solution
Im not sure that you or anyone really wants my total solution though, my choke I expect will use sendust toroidal cores or and possibly a few EE65 gapped cores. I am not going down the iron core path unless all else fails - it's a me thing...I will concede though that adding some milliohms of resistance in series with my sendust choke did reduce the grunt a little, so a more lossy choke is not all bad. Murphy duplicated the Warp inverse opto FET drive part also and has been trying to kill FETs ever since, but I believe a solution to this has eluded him to date.
My controller board uses the little 2mA/2ma voltage sense transformers and I currently have 2 working versions for the inverse opto drive, one with the EG8010 IC the other using Poidas nano code. I would probably advise the nano version and if you want to play with some ready-made (blank) circuit boards I could also help with that.
What does your idea of a finished inverter look like in your head, and how much of it do you want to roll your own ie pcb design etc etc. If discussing in the Forum has any issues for you and you'd prefer a couple of PM's that's fine too. But ultimately success or failure is all good and published results are all helpful to others in the Forum.
Edited 2022-12-31 06:53 by wiseguy