a. Calculate the diameter of the turbine blades for both geared and direct drive options to give 100 kW of electrical output power. The density of air is 1.225 kg/m³. The full-load efficiency of the geared induction machine (IM) is 92% and overall efficiency of the combined induction machine and gear is 85%. The full-load efficiency of the direct drive permanent magnet (PM) machine is 90%. b. Calculate the angular velocity of the turbine when the wind speed is 12 m/s. c. There are two possible options: use a 1500 rpm doubly fed induction generator and a gearbox or use a direct drive PM synchronous generator. The induction generator has a torque density of about 1 Nm/kg. The PM synchronous generator has a torque density of 5 Nm/kg. The torque density of a gearbox calculated at the low speed end is 20 Nm/kg. Estimate the total masses of the geared and direct drive motor options.
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Calculate the diameter of the turbine blades for both geared and direct drive options to give 100 kW of electrical output power. ** Show more…
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