How the alternator can be protected from inter-turn fault?

How the alternator can be protected from inter-turn fault?
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1 Answer

Answer :

Inter-turn fault Protection: Figure shows scheme for one phase only. It is identical for other phases. Under normal working condition, the two currents in the stator winding sections (S1 and S2) are identical and by virtue of the cross connected CT secondaries, the relay current is zero, hence no relay operation. But when one of the windings is faulty (inter turn fault) its current differs and hence the two CT secondary currents are different, due which the difference current is diverted through the relay coil to operate it, leading to isolation of the alternator from the power system.

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