Synchronous Motors The speed of a synchronous motor can be changed by varying _______ Field excitation Supply frequency None of the listed here Mechanical load Field excitation Supply frequency None of the listed here Mechanical load ANSWER DOWNLOAD EXAMIANS APP
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 under-excitation lagging power factor with over-excitation leading power factor with over-excitation no change of power factor leading power factor with under-excitation lagging power factor with over-excitation leading power factor with over-excitation no change of power factor ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors Hunting in a synchronous motor cannot be due to variable supply voltage variable frequency variable load windage friction variable supply voltage variable frequency variable load windage friction ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors In a synchronous motor, the magnitude of stator back emf depends on _____ Dc excitation only Load on the motor Speed of the rotor Both the speed and rotor flux Dc excitation only Load on the motor Speed of the rotor Both the speed and rotor flux ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors For reciprocating compressor, the synchronous motor is designed to have pull in torque of about ______ times the full load torque. 5 2 0.5 6 5 2 0.5 6 ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors In a synchronous motor which loss varies with load ? Bearing friction loss Copper loss Windage loss Core loss Bearing friction loss Copper loss Windage loss Core loss ANSWER DOWNLOAD EXAMIANS APP
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