usage eg8010 for grid tie inverter

Hi all.
I have crazy idea, try to use eg8010 as a grid tie invertor's sinusoid generator. There are many cheap boards with eg8010+ ir2110, and DYI boards for offgrid inverters.

There is two aspects.
1. Voltage level - no problem (use refernce setup DAC or UART managment)

2. Phase with target net, right, there is a problem but lets imagine - this chip have at least 255 stages of frequensy setup for 0-100Hz range, it gives a resolution something about 0.39 Hz
(49.8Hz for 127 and 50.19Hz for 128). Yep resolution is not the best, but even with this two values (for example 127/128) we can keep synchronization in quite good range (its about 0.5% drift, I think zero crossing detector will give worst accuracy in real conditions).

So algo to control phase drift is next: we measure time difference between zero crossing on line and rising edge on eg8010 unipolar key. If delay positive we use 127 value, other way 128. But its faster to use for this purpose DAC instead of UART (plus I hope with DAC eg8010 will have more resoltion - it should be tested).
I've tried such algo on stm32+IRAMX16 (when it was alive ).
The only one thing make me worry - how fast eg8010 apply changes (on this duty cicle, on next half of waveform, on next period...)

I would like to heards your opinions, advises and so on, please.

PS. Sorry for my english (its not my native).

0.39 Hz frequency difference means 2.8 degree phase error increase per sine period. You need a quite large coupling inductor to keep the error current within manageable limits. Or multiple frequency updates per period.

The phase and voltage control loops have to be implemented in a microcontroller. Even it works, don't see the advantage over a pure microcontroller solution.

Sure, better way is to implement all logic on separate microcontroller, but eg8010 (as I can see from documentation and amount of usage in inverters) specific developped chip for concrete purposes, its not commonly used stm32 for example (wich BTW has exelent PWM+DMA engine) I have no idea how stable it'll work on +1kwt load. Plus write, debugg, test all the program feathures presented in eg8010 it takes much more time and resources than simple implementation zerro crossing detector and phase shifting.

Any way as soon as I get the board samples I'll try it first, if possibility of regulation will be poor - I'll remove eg8010 from board and replace it by stm32 with same logic (initially I planed to do it in such way, but then start thinking aboout economy some time when seen that eg8010 has V and F regulation)

How you think, what is the maximum possible zero crossing error could be allowed with load something about 1kwt+ without fireworks?

What's the inductance of your coupling inductor? If you know it, you can calculate the current caused by phase and voltage mismatch.

3-4mH, but I don't know how to calculate current