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Transformer law, Ohm's law and generator power
Voltage follows the turns ratio, V = I × R, and a generator's power in kW is kVp × mA ÷ 1000.
The transformer law
A transformer changes voltage using two coils wound on an iron core. Alternating current in the primary coil creates a changing magnetic field that induces current in the secondary coil. The transformer law says voltage changes by the turns ratio: Vs ÷ Vp = Ns ÷ Np, where V is voltage, N is the number of turns, p is the primary and s is the secondary. Current changes the opposite way: Is ÷ Ip = Np ÷ Ns. Power stays about the same, so when voltage goes up, current goes down.