State the factors, for the choice of electrical system for an aero turbine.

The choice of electrical system for an aero turbine is guided by three factors:• Type of electrical output: dc, variable- frequency ac, and constant- frequency ac.• Aero turbine rotational speed: constant speed with variable blade pitch, nearly constant speed with simpler pitch- changing mechanism or variable speed with fixed pitch blades.• Utilization of electrical energy output: in conjunction with battery or other form of storage, or interconnection with power grid.