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I would check out the SMA Sunny Island 4548/6048 grid manager, you MIGHT be able to tie a micro inverter (MI) system to this grid manager, through a 2:1 transformer, or by some other means. Just know that the MI's must see normal low impedance grid voltage to function at all. The other possibility - look at Princeton Power and Apollo Solar. As far as I know this is uncharted territory so some research is required.This is a recurring question for me in my Soar Academy classes and is gaining traction. I want to add that the SMA Sunny Island can be used with any solar/wind inverter regardless of make. SMA is coming out with our own micro inverter after SPI and it will be able to be used with the SI45/50/6048U inverters, although initially, it will not respond to the Sunny Island frequency shifts.
That being said, the only issue with a non-SMA inverter will occur when the following three conditions exists:
1. The grid is out (or in a standalone system)
2. The batteries are fully topped off
3. There is no demand on the protected loads panel
If these three conditions are met, the Sunny Island will increase the micro grid frequency to throttle the RE inverters down to 0W to prevent battery overcharge. With a non-SMA inverter, it will not respond to these frequency shifts and as soon as the frequency hits the UL1741 limit of 60.5Hz it will immediately disconnect from the grid. Worst case, you will have to wait 5 minutes when the Island recognizes a demand and the isolation relays in the inverters will be overexercised. Not a big deal really.
However, there is a word of caution as some micro inverter companies will void their warranty if used in a grid tied backup/stand alone application.