GE new 4 megawatt permanent magnet

Re: GE new 4 megawatt permanent magnet

Here is a brochure (PDF) for a 2.5 MW PM but geared wind turbine.

The electrical system design of the 2.5 MW wind turbine consists
of a permanent magnet generator and full power conversion.
In the lower tower section, the power module efficiently converts
the energy from the permanent magnet generator into power that
provides frequency and voltage control required by transmission
system operators. The integration of the converter and transformer
down tower , rather than the nacelle, ensures that vibration loads
do not affect the reliability of the power electronics. The converter
cooling system has been designed to minimize moving parts
for reliability and features passive coolers that use the same
wind that powers the turbine.

My guess is that the system is sort of like an MPPT solar charger/GT inverter... The front end take the AC power (wild frequency/voltage) and optimizes current conversion to maximize power=voltage*current. That energy is stored (probably in a capacitor bank) and then converted into the voltage/current/phase needed for the utility power.

Since there is no relationship between input power and output power (other than total power converted--no frequency/voltage issues)--then there is no turbine speed regulation issues (other than to maximize true output power by adjusting torque from the alternator to let the blades spin at optimum speed).

-Bill