Stability of electrical frequency

We're setting up a hydro power system for mining. From what I gather, the output frequency (around 60hz) could fluctuate a bit depending on how effectively we control the valve that supplies water to the turbine. Could this potentially damage the S19 miners?

How much variation do you expect? I'd suggest designing the system to keep within the PSU specs.... The specs show it can handle 47hz to 63hz ...

I have an idea  You could convert the AC voltage from your generator into pure DC and then convert that into 220v AC with an accurate frequency

Some guy on the internet was getting +/- 3hz using a Arduino based feedback system for the water feed valve.