Answer / kaami

advantages of DC generating station

1)since, V=IZ where Z=IR+reactance. As, f=0,
so Z=IR.
2)No skin effect in DC
3)natural capacitance in overhead transmission in AC cause the charging current to flow in overhead line thus causing the loss in transmission line. since in dc, charging current is absent so no natural capacitance.

advantages of AC generating station

1)output voltage due to DC machine are limited mainly due to restriction on rotor and carbon brushes. Output voltage from ac machines can be achieved very high upto 33kv because power is taken from the stationary part.
2)main advantage is stepping up or stepping down voltage to transmit to large distances.

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