Manufactures want to lock you in to their particular products with expensive control equipment, its a shame they don't say this in their product literature.
With help from 'Oztules' I went the simple, robust, and very importantly cost effective 'OzInverter'.
AC coupling is important for us here, as its a cheap way of powering our 230vac Mini Grid, so we are using lots of smallish 3kW GTI's with PV. The Mini Grid powers our needs for our small community of houses/buildings.
Therefore a 6kW 'OzInverter', or my 10kW 'OzInverter' can supply and run the Mini Grid, any bigger Inverter just hammers the batteries, or you need a very big, expensive, battery bank.
Very soon I will have another 4off 3kW GTI's, (toroid type cheap as chips Old stock) powering in to the 'OzInverter' created Mini Grid.
'Oztules' reckons that the 6kW 'OzInverter' can handle 8kW of Back charging from the GTI's, I have only so far managed/tested 5kW with out any problems.
The 'OzInverter' back charges, its the H bridge. As the batteries fill there is a push back from the batteries and the 'OzInverter' AC output voltage rises slightly and the GTI's quickly drop out/shut down. (the manufactures set the drop out voltage according to the agreed Nations format).
I can fine tune my GTI's for a sequential shut down and a quicker start up procedure.
No way would we use the HZ frequency raising to control stuff, washing machine, micro wave, cooker timer etc don't like a rise of 10HZ.
Note, I also have a fail safe GTI switch off system, (never operated so far), that is activated by ancillary relay on my Midnite classic 200 DC controller. I have 5kW of PV and 3off 3.7m wind turbines that are direct connected and charging my 1300ah 48vdc batteries. At present I use the DC controllers to finish the batteries charging regime.
So the 'OzInverter', running from my precious batteries, is bridging the gap while the GTI's AC output starts up again.
Keep it simple, Robust and Cost is important, so I am always trying to keep things simple but safe.
Control equipment..... so my 2off DC controllers, and 4off diversion controllers, are the biggest buy in expense so far, and Yes, I have the biggest circuit breakers MidNite sell, but otherwise that's it.
Eraser, I see you have a 30kW wind turbine? I am not sure what or who's it is but its output control is going to be interesting if you are not using up that excess.
I have 8kW of heavy duty dumpload heaters operating from diversion controllers for my 3 wind turbines, and on those stormy windy winter nights its nice to get extra heat.
Note, the Dump load heaters diversion controllers are also useful for keeping the batteries spot on charge, after all they are just directly connected to the batteries and just dumping excess.
Please ensure that the Dump load heaters are not fastened to anything combustible or even near anything combustible . Yes, I have had some hair raising moments, after 8 years of experience mine now stand on movable metal cradle in the middle of a room.
DC PV Solar Controllers, ..... I think 'Oztules' is looking at them now. So that should bring the cost even further down in regards creating your own Mini Grid. And best of all, we are not beholden to any particular Manufacture.
Personally if I was to do all this again, I would just stick with PV and more PV, its now a very good cost and easy to control.
Edit..... Brilliant Bruce, ....... I can now edit my above post sometime after originally posting, I noticed a mistake in my description on the dump loads so all sorted.