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 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 lagging power factor with over-excitation leading power factor with under-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-out torque pull-in torque pull-up torque None of these pull-out torque pull-in torque pull-up 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 Motor speed Applied voltage of the motor Power factor of power drawn by the motor Any of the above Motor speed Applied voltage of the motor ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors A synchronous machine with low value of short-circuit ratio has good voltage regulation good speed regulation high stability limit lower stability limit good voltage regulation good speed regulation high stability limit lower stability limit ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors In a synchronous motor which loss varies with load ? Core loss Copper loss Bearing friction loss Windage loss Core loss Copper loss Bearing friction loss Windage loss ANSWER DOWNLOAD EXAMIANS APP
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