Synchronous Motors As the load is applied to a synchronous motor, the motor takes more armature current because The increased load has to take more current The rotor by shifting its phase backward causes motor to take more current The back e.m.f. decreases causing an increase in motor current The rotor strengthens the rotating field causing more motor current The increased load has to take more current The rotor by shifting its phase backward causes motor to take more current The back e.m.f. decreases causing an increase in motor current The rotor strengthens the rotating field causing more motor current ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors Damper winding in a synchronous motor________ Serves to start the motor Improve pf of the motor Increases hunting of the motor Reduces windage losses Serves to start the motor Improve pf of the motor Increases hunting of the motor Reduces windage losses ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The efficiency of a properly designed synchronous motor will usually fall in range 60 to 70% 99 to 99.5% 75 to 80% 85 to 95% 60 to 70% 99 to 99.5% 75 to 80% 85 to 95% ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The power factor correction capability of a loaded synchronous motor _____ with the increases in mechanical load. None of the listed here Decreases Remains unchanged Increases None of the listed here Decreases Remains unchanged Increases ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors A synchronous motor can develop synchronous torque while over-excited when under loaded only at synchronous speed below or above synchronous speed while over-excited when under loaded only at synchronous speed below or above synchronous speed ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors A synchronous machine with large air gap has a higher value of stability limit a higher synchronizing power which makes the machine less sensitive to load variations a small value of inherent regulation all of the listed here a higher value of stability limit a higher synchronizing power which makes the machine less sensitive to load variations a small value of inherent regulation all of the listed here ANSWER DOWNLOAD EXAMIANS APP