a) Reactance due to armature reaction of the machine b) Reactance of synchronous machine c) Reactance due to leakage flux d) Combined reactance due to leakage of flux and armature reaction Ans: (d)
a) True b) False Ans: (a)
a) True b) False Ans: (b)
i) Synchronous Impedance Method ii) M.M.F. Method iii) Potier Triangle Method Ans: ()
a) The value of synchronous impedance found is always less than actual value b) The value of synchronous impedance found is always less than the actual value c) The value of the synchronous impedance is independent of saturation d) The reactance due to armature reaction is considered separately Ans: (b)
a) True b) False Ans: (a)
a) M.M.F. Method b) Potier Triangle Method c) Synchronous Impedance Method d) None of the above Ans: (b)
a) Proper machine b) Mechanizing c) Synchronizing d) Asynchronizing Ans: (c)
i) The terminal voltage for the incoming alternator must be same as bus bar voltage. ii) The speed of the incoming machine must be such that its frequency (=pn/120) equals bus bar frequency. iii) The phase of the alternator voltage must be identical with the phase of the bus bar voltage. It means that switch must be closed at (or very near) the instant of the two voltage have correct relationship. Ans: ()
a) True b) False Ans: (a)
a) True b) False Ans: (a)
a) The machine will burn b) Both of the machines will stop c) The synchronization torque will be produced to restore further synchronism d) Synchronization cannot be attained automatically Ans: (c)
a) The reactive component of the output is changed b) The active component of the output is changed c) The power factor of the load remains constant d) (a) and (b) takes place simultaneously Ans: (a)
a) True b) False Ans: (a)
a) True b) False Ans: (b)