Guru
Joined: 07/11/2007
Location: AustraliaPosts: 1904
| Posted: 01:41am 04 Nov 2017 |
A last comment about VFB, it may be pointless for some to discuss this but to me it helped a great deal to understand why and how it does what it does.
So, thanks guys. I'm sure I'm not the only one having benefited from this discussion.
And, it managed to solicit above another point of info about which I was unaware of. Namely, the location of the little transformer with relation of the secondary capacitor. I always thought it odd to stick it on the side of that little transformer, now it appears there is a good reason for that.
Since I'm building my inverter "from scratch" I really did not want to copy oztules PCB layout. Om my version, the mains circuit (little transformer, current sensor, rectifiers) are on a separate board. The capacitor is directly on top of the big toroid. Luckily with my latest arrangement these parts are closely together, only some 100mm of heavy gauge wire is between the little transformer and the capacitor.
My pre testing (no toroid/ Mosfets connected) of the control board is just about complete with all EG8010 functions working well. I did power the 230v side of the little tranny from mains and used the rectified 12v output to provide VFB.
There was some high frequency noise on the very peaks of the cycles and I could reduce this to ~50mV pp by simply loading the rectified 12V secondary with 560 Ohm. Giving the little tranny something to do so to speak.
Is 50mV VFB noise acceptable?
Klaus