Electrical Machines The oscillation in a synchronous motor can be damped out by oscillation cannot be damped. maintaining constant excitation. providing damper bars in the rotor pole faces. running the motor on leading power factors. oscillation cannot be damped. maintaining constant excitation. providing damper bars in the rotor pole faces. running the motor on leading power factors. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The mmf produced by rotor currents of a 3 - Φ induction motor rotates at synchronous speed with respect to rotor. rotates at the speed of rotor in the air gap. is at standstill with respect to stator mmf. rotates at slip speed with respect to stator mmf. rotates at synchronous speed with respect to rotor. rotates at the speed of rotor in the air gap. is at standstill with respect to stator mmf. rotates at slip speed with respect to stator mmf. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a loaded DC generator, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will improve with rise in terminal voltage. deteriorate with rise in terminal voltage. deteriorate with fall of terminal voltage. improve with fall of terminal voltage. improve with rise in terminal voltage. deteriorate with rise in terminal voltage. deteriorate with fall of terminal voltage. improve with fall of terminal voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The results of a slip test for determining direct axis (Xd) and quadrature axis (Xq) reactances of a star connected salient pole alternator are given below Phase values: Vmax = 108 V ; Vmin = 96 V Imax = 12 A ; Imin = 10 A Hence the two reactances will be Xd = 9Ω and Xq = 9.6Ω Xd = 9.6Ω and Xq = 9Ω Xd = 10.8Ω and Xq = 8Ω Xd = 8Ω and Xq = 10.8Ω Xd = 9Ω and Xq = 9.6Ω Xd = 9.6Ω and Xq = 9Ω Xd = 10.8Ω and Xq = 8Ω Xd = 8Ω and Xq = 10.8Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In alternator, the rotary part is magnetic field poles. armature. none of these. core. magnetic field poles. armature. none of these. core. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a given torque, reducing diverter resistance of a DC series motor causes decrease in speed but armature current remains the same. decrease in speed demanding less armature current. increase in speed but armature currnet remains the same. increase in speed demanding more armature current. decrease in speed but armature current remains the same. decrease in speed demanding less armature current. increase in speed but armature currnet remains the same. increase in speed demanding more armature current. ANSWER DOWNLOAD EXAMIANS APP