Synchronous Motors A synchronous motor connected to infinite bus-bars has at constant full load, 100% excitation and unity power factor. On changing the excitation only, the armature current will have lagging power factor with over-excitation leading power factor with under-excitation leading power factor with over-excitation no change of power factor lagging power factor with over-excitation leading power factor with under-excitation leading power factor with over-excitation no change of power factor ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as pull-out torque None of these pull-in torque pull-up torque pull-out torque None of these pull-in torque pull-up torque ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors Change of D.C. excitation of a synchronous motor changes Applied voltage of the motor Motor speed Power factor of power drawn by the motor Any of the above Applied voltage of the motor Motor speed Power factor of power drawn by the motor Any of the above ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors A synchronous machine with low value of short-circuit ratio has good voltage regulation lower stability limit high stability limit good speed regulation good voltage regulation lower stability limit high stability limit good speed regulation ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors In a synchronous motor which loss varies with load ? Core loss Bearing friction loss Copper loss Windage loss Core loss Bearing friction loss Copper loss Windage loss ANSWER DOWNLOAD EXAMIANS APP
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