The OzInverter.

Brief notes on its substance and its development.

Firstly, Why the name OzInverter?....

It is named after the Renewable Forums member name ‘Oztules,’ Flinders Island, Tasmania, Australia, who has helped me achieve a simple, robust, powerfull and cost effective Inverter. His work is ‘Open source' with his experiments and actual builds, are detailed in the below mentioned World Wide Renewable Energy Forums:-

For decades I had been searching for a simple, robust 48vdc (batteries) to 230vac 50HZ Pure Sine Wave Inverter that will actually do and deliver the kW’s it says it can, and also hold a stable HZ frequency. Oztules helped me to achieve my dream Inverter, and it runs beautifully.

Most folk with normal homes that are Off Grid or want to be, need about 3 to 5kW of power around the house. Sometimes they may need 6kW for ½ hour or so, or infrequently up to 15kW , the OzInverter will do this, that’s if your batteries can take/handle it.

AC Coupling, Mini Grid.

With the arrival of GTI’s, (Grid Tie Inverters) that uses the PV on the roof of houses, and subsequent lowering of prices, and the availability of second hand or old stock, we can now directly feed the AC output from the GTI’s into our OzInverter created mini AC grid. So we no longer need as many costly DC battery chargers/controllers.

If you are not using the GTI’s output around the home, then the Excess 230vac AC will backfeed through the OzInverter and become DC and charge your batteries, which is what I do. Some sort of battery charging regime will be required.

As your batteries fill and become full, the OzInverter raises the 230vac voltage slightly, and with most normal GTI’s this then goes outside their normal working parameters, and hence the GTI shuts down. In the book, I also talk about a fail safe protection for the batteries.

The above Photo of the inside, shows the Chinese PCB boards, they are actually okay, but QC issues, the required modifications and availaibitty problems has recently pushed us forward to create Our Own Power Board and OzControl Board.

What can the OzInverter do?.

The Toroid transformer is the key here, for a 6kW Inverter we are talking about 26kg to 30kg of laminated wound silicone iron core, with a centre hole say about 90 to 100mm diameter. This will then match with our New Power Board and its matching New OzControl board.

No commercial available toroid will do, we stack cores, do the maths on the cross section mm/2, (real working figures), gives us a rough guide on the Secondary windings and Primary windings from the known ratio. (Its in the book).

We wind the large toroid by hand, (photo example of the table set up is in the Book), as no commercial winding machine can get into our stacked cores. We mylar tape and epoxy each winding, this stops the buzzing and movement of the windings so eliminating early failure due to internal vibration and the consequent shorting out.

We test each winding for correct turns etc, we wind a low count single primary core, about 50mm/2, better cooling abilities, we bench test it and test the secondary and amend the primary turn to get what we want.

The New Power Board and the New OzControl board have been designed for through hole components and that are readily available, and designed for ease of self-manufacture. They will take 6kW and up to 15kw but cooling is the key here, again its in the book with the OzCooling circuit and Board.

If you follow the book’s methods, you end up with a robust, simple, stonking big, serious Power Inverter, and all at a very reasonable Price.

Making a Low cost, simple and robust 6kW, 50HZ Pure Sine Wave, 48vdc to 230vac, INVERTER.

Those that have followed ‘Oztules’, wonderful endeavours will understand that for posterity and easy reference, and for my boys, I have put together a Book that gives the technical, describes and shows (lots of colour photos), the OzInverters I built and now run.

There is no money in this book publication, we are not a commercial organization, we just want our costs and P+P, but it’s good to finally see all that Information is in one place, in a Book.

March 2016, the original Power & Control board from the Chinese manufacturer PJ, (PowerJack) became difficult to obtain, along with questionable QC and some poor manufacturing. A New Power board was created to match the OzControl board that uses the 8010 chip.

Extra time was taken on the design and construction of the PCB’s, so to ensure that all components and parts of the New OzInverter were easily obtainable.

“Looking good.. now with just off the shelf components, we can finally make a real inverter.. that is easy to fix as well. utopia indeed for remote living I don't think any other unit on the market can say that.... usually you have to replace propriety boards... if you can get them. . ‘oztules.’

The Book. ISBN 9780993590306. A4 Size, 76 printed pages, 151 colour photographs, 14 diagrams.

And a PCB Making Supplement containing:-

A4 size, 4 pages colour photographs and details of the PCB boards, and construction tips.

7off A4 size, loose leaf….. The 6-15kW Power Board, individual sheets of A4 PCB construction Masks/patterns, at real 1 to 1 size.

1off sheet of A4….. The OzControl Board, with all three PCB construction Masks/patterns, at real 1 to 1 size.

2off A4 size, ‘The Power Board Component List’ and suppliers where appropriate. ‘The OzControl Board Component List’ and suppliers where appropriate, and the OzCooling Board Masks and components List.

What’s in the Book ?

Everything, explaining & showing …. From the Core, winding the toroid, to the PCB’s and all the other necessary components to give you a Real Working 6kW OzInverter.