Electrical Machines The introduction of interpoles in between the main poles improves the performance of a dc machine, because a counter-emf is induced in the coil undergoing commutation the interpoles produce additional flux to augment the developed torque the flux waveform is improved with reduction in harmonics the inequality of air-gap flux on the top and bottom halves of the armature is removed a counter-emf is induced in the coil undergoing commutation the interpoles produce additional flux to augment the developed torque the flux waveform is improved with reduction in harmonics the inequality of air-gap flux on the top and bottom halves of the armature is removed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field weakening control method is used for the _________ ? above rated speed both A and B below rated speed None of these above rated speed both A and B below rated speed None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines How can the synchronous speed of a 3 - Φ IM be varied? Both (A) and (B). By varying number of poles. By varying supply voltage. By varying the supply frequency. Both (A) and (B). By varying number of poles. By varying supply voltage. By varying the supply frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of IM the torque is inversely proportional to √slip. directly proportional to slip2. directly proportional to slip. inversely proportional to slip. inversely proportional to √slip. directly proportional to slip2. directly proportional to slip. inversely proportional to slip. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following DC Motor uses 4-point starter? DC shunt motor with armature resistance. DC compound motor. DC series motor. DC shunt motor with field weaking control. DC shunt motor with armature resistance. DC compound motor. DC series motor. DC shunt motor with field weaking control. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of 3 - Φ IM, plugging means locking of rotor due to harmonics. interchanging two supply phases for quick stopping. starting the motor on load which is more than the rated load. pulling the motor directly on line without a rotor. locking of rotor due to harmonics. interchanging two supply phases for quick stopping. starting the motor on load which is more than the rated load. pulling the motor directly on line without a rotor. ANSWER DOWNLOAD EXAMIANS APP
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