Synchronous Motors In a synchronous motor, the magnitude of stator back emf depends on _____ Dc excitation only Speed of the rotor Load on the motor Both the speed and rotor flux Dc excitation only Speed of the rotor Load on the motor Both the speed and rotor flux 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 no change of power factor leading power factor with over-excitation leading power factor with under-excitation lagging power factor with over-excitation no change of power factor leading power factor with over-excitation ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The power factor of a synchronous motor is better than that of induction motor because stator supply is relieved of responsibility of producing magnetic field synchronous motor has large air gap mechanical load on the motor can be adjusted synchronous motor runs at synchronous speed stator supply is relieved of responsibility of producing magnetic field synchronous motor has large air gap mechanical load on the motor can be adjusted synchronous motor runs at synchronous speed ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors A synchronous motor can develop synchronous torque while over-excited below or above synchronous speed only at synchronous speed when under loaded while over-excited below or above synchronous speed only at synchronous speed when under loaded ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors Damper winding in a synchronous motor________ Serves to start the motor Reduces windage losses Improve pf of the motor Increases hunting of the motor Serves to start the motor Reduces windage losses Improve pf of the motor Increases hunting of the motor ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors In a synchronous motor, the forced vibrations will be maximum when driving Any of the listed here A reciprocating air compressor A centrifugal pump A centrifugal blower Any of the listed here A reciprocating air compressor A centrifugal pump A centrifugal blower ANSWER DOWNLOAD EXAMIANS APP