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 no change of power factor leading power factor with under-excitation leading power factor with over-excitation lagging power factor with over-excitation no change of power factor leading power factor with under-excitation leading power factor with over-excitation 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-up torque pull-in torque pull-out torque None of these pull-up torque pull-in torque pull-out torque None of these ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors Change of D.C. excitation of a synchronous motor changes 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 Applied voltage of the motor Motor speed ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors A synchronous machine with low value of short-circuit ratio has high stability limit good voltage regulation good speed regulation lower stability limit high stability limit good voltage regulation good speed regulation lower stability limit ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors In a synchronous motor which loss varies with load ? Windage loss Bearing friction loss Core loss Copper loss Windage loss Bearing friction loss Core loss Copper loss ANSWER DOWNLOAD EXAMIANS APP
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