Electrical Machines In a synchronous motor when the rotor speed exceeds the synchronous speed during hunting negative sequence currents are generated. the damper bars develop induction generator torque. the damper bars develop synchronous motor torque. the damper bars develop induction motor torque. negative sequence currents are generated. the damper bars develop induction generator torque. the damper bars develop synchronous motor torque. the damper bars develop induction motor torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A three phase 400 V, 6 pole, 50 Hz, squirrel cage induction motor is running at a slip of 5%. The speed of stator magnetic field with respect to rotor magnetic field and speed of rotor w.r.t stator magnetic field are zero , - 50 rpm. zero, 950 rpm. 1000 rpm, - 50 rpm. 1000 rpm, 950 rpm. zero , - 50 rpm. zero, 950 rpm. 1000 rpm, - 50 rpm. 1000 rpm, 950 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : 1. interpole windings are connected in series with armature windings 2. polarity of interpoles must be the same as that of the main poles in advance 3. distortion of the main field under the pole shoes is not affected by the use of interpoles From above, the correct answer is 1 and 3 2 and 3 1 and 2 1 alone 1 and 3 2 and 3 1 and 2 1 alone ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous motor is supplying a load at unity power factor. If the load on the motor is increased keeping its excitation and terminal voltage constant, the power factor will become lagging None of these will remain the same will become leading will become lagging None of these will remain the same will become leading ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To control the speed of an induction motor, the supply frequency is reduced by 10%. For the same magnetizing current to remain constant, the supply voltage must be reduced by 10% increased by 20% increased by 10% reduced by 20% reduced by 10% increased by 20% increased by 10% reduced by 20% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor has more stability None of these both motors has same stability cylindrical motor salient pole motor None of these both motors has same stability cylindrical motor salient pole motor ANSWER DOWNLOAD EXAMIANS APP
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