A 25 MVA, 4-pole, 50 Hz turbo-alternator has an inertia constant H = 5 kW sec/kVA. The stored kinetic energy in the rotor at synchronous speed is

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 Question:

A 25 MVA, 4-pole, 50 Hz turbo-alternator has an inertia constant H = 5 kW sec/kVA. The stored kinetic energy in the rotor at synchronous speed is

Explanation:

Machine rating G = 25 MVA

Inertia constant H = 5 kW sec/kVA

Now kinetic energy stored (K. E.) = Machine rating * inertia constant

K. E. = G*H

K. E. = (25 MVA) * (5 kWsec/kVA)

K. E. = 125 MJ

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