This may amuse or assist others, and takes me on another voyage of discovery. Yet again a big Thanks to ‘Oztules’.
See other links here on this forum regards OzInverter builds, ‘Oztules’ builds, the PCB’s etc, ... POWER board, OzControl board, and the double OzCooling board. We can Now make a complete powerful OzInverter without the need of any outside manufacturer.
My 6kW OzInverters are working flawlessly and doing what I wanted, especially with the AC coupling and the AC back charging. Remember we are shutting down the GTI’s with a slight rise on the AC output voltage from the OzInverter created Mini Grid, when the batteries start to reach full charge.
Some of you may be aware of my total untrust of the HZ increase rise that some Inverter manufacturers use, a very unpleasant personal experience, (at 54Hz my household synchronous motors, Microwave, washing machine etc will not run correctly). Especially when you have a mix of renewable energy DC ,(my wind turbines) and AC charging coming in. (scarily, I read recently that there are moves ahead to make HZ increase a standard amongst all Inverter Manufacturers, talk about manufacturer lock in!!!!!!).
So this BigOzInverter build will push the boundaries a bit. I am looking at a constant 8kW to 10kW output with large surges.
My present battery bank is 48v 1300ah, so most of the time I have GTI’s, (Solar Grid Tie Inverters) putting their power into my OzInverter created Mini Grid. But, there will be times in the future where the BigOzInverter will be required to step in for a few minutes or so.
I talked about my BigOzInverter design here…… http://www.anotherpower.com/board/index.php/topic,1117.0.html?PHPSESSID=h7jd5l4edljl6k4ls18pgfj4i1The Toroid Build
So I have a 38kg core, at 230mm OD, 100mm centre hole and 140mm thick/high.
80 turns of 6 off, 1.8mm diameter secondary and 10 turns of 1 off, 75mm/2 for the primary.
The 38kg (about 83lbs) core is heavy and awkward to lift and turn without damaging the enamelling on the windings. The 1st photo shows an amended winding table with sufficient space to safely get my fingers under the core and cleanly lift. There are 6 rubber mats cut out, each at 1.1mm thick taped to the table. This works well as the rubber gives and spreads the weight without collapsing or being too stiff.
Differences with Testing the Secondary windings.
My normal 25w 230vac test bulb that I use on the 6kW OzInverters was just too small a wattage for the toroid to step up to full 230vac on each winding, and my workshop 20 amp MCB would trip out.
However, replacing the 25w with a 100w 230vac test bulb works fine, as the interim step for the each secondary taking a full 230vac. But be warned the 100w bulb will not illuminate, the toroid seems to want everything.
These first 2 secondary windings are fine and each gives the same Induced voltage readings.
The 2nd Photo shows the 100w bulb that is now bypassed with that insulated croc clip, so the toroid first secondary winding is taking the full 238vac Mains, and inducing 238vac in the second secondary winding. And Yes, I will tidy up the windings before I resin coat them, but I always test first.
WARNING. Yes,! I should know better!
230vac is serious and will probably KILL you, so be very very careful. Check and double check.