alt.energy.renewable

Punjab The Sailor Man wrote:
> How do you get the frequency at 60hz if the wind speed keeps changing?

Most small wind turbines are designed to charge batteries and
usually run wild frequencies that are rectified into DC. It's
not uncommon for these to have three sets of coils out of phase
with each other to produce fairly smooth DC output.

Big utility scale machines have controllers that let the turbine
freewheel until it gets up to speed and then they hook it to the
grid. Once hooked to the grid it's stuck at that speed. It can't
go faster, it just generates more power. If it slows down then
the controller disconnects it from the grid and it spins freely.
Some of them use gearboxes and servos to vary the pitch of the
blades so they can operate over a greater range of wind speeds.

Anthony