Diesel Generator Tech

The control of generator stator voltage is realized by adjusting the magnitude of rotor excitation current. The excitation corresponding to the amount of electricity generated is normal excitation. When the stator operating voltage is higher than the rated voltage, it is called overexcitation. Conversely, the stator operating voltage below the rated voltage is called underexcitation. In practice, there is a definite positive and negative value above or below the rated voltage. Different generators have different excitation control system and different excitation values. Generators and transformers are composed of iron core windings. If the applied voltage of windings is U, the turn number is W, the cross section of iron core is S, and the magnetic density is B, then U = 4.44fWBS. Because W and S is definite number, so it is written in B=KU/f, K=1./4.44WS, for each particular generator or transformer, K is a definite number. We can know from B=KU/f: the increase of voltage and the...