The synchronous reactance of the synchronous machine is ______________. (A) Ratio between open circuit voltage and short circuit current at constant field current (B) Ratio between short circuit voltage and open circuit current at constant field current (C) Ratio between open circuit voltage and short circuit current at different field current (D) Ratio between short circuit voltage and open circuit current at different field current

The synchronous reactance of the synchronous machine is ______________.
 (A) Ratio between open circuit voltage and short circuit current at constant field
current
 (B) Ratio between short circuit voltage and open circuit current at constant field
current
 (C) Ratio between open circuit voltage and short circuit current at different field
current
 (D) Ratio between short circuit voltage and open circuit current at different field
current
by

1 Answer

Answer :

Ans. A
The Synchronous reactance of a synchronous machine is a total steady state reactance,
presented to applied voltage, when rotor is running synchronously without excitation.
 Therefore , XS = Ef
 / IS
 = Emf of OC for same If
 / short circuit current
by

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