A friend is developing wind turbines and needs some advice

The output of the turbine is 3-phase. Below 400rpm the coils
are configured as star. Above that, delta (I think I got that the
right way around - he took his notes). The 3-phase presently
goes to a converter to make several amps of 12V for battery
charging

At a certain point, roughly 400Hz, the delta configuration gives
a lot more wattage

To make the switch from star to delta, he has a circuit based
on the LM2917 V-to-F chip, and that operates a relay. The
circuit needs at least 50mA

What he wants to do is take a tap from the 3-phase terminals
to get 12V-ish volts to run this circuit. Although the circuit has
a 16V zener clamp and 7808 regulator on V+, so actually 8V
would do. He doesn't want to have an extra wire coming back
from the converter output to supply the 12V

I suggested taking two of the 3-phase terminals on the turbine
head and feeding them into a bridge. He tells me that at high
speed, the turbine can put out up to 110V (he didn't specify
pk-pk or RMS). At low speed, just a few volts, obviously

Is what I suggested safe/practical ? Also, how would I cope
with such a wide range of input voltages into perhaps a SMPS
or linear regulator ? Bit out of my comfort zone

TIA

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