Electrical Machines The DC generator runs at a speed of 1000 rpm and flux per pole is 0.2 Wb, number of poles are 2 the winding is wave wound and having 480 conductors. The critical speed is 1200 rpm. Then the generated emf ( Eg ) 1600 Volt. 0 Volt. 2000 Volt. 1500 Volt. 1600 Volt. 0 Volt. 2000 Volt. 1500 Volt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of a DC motor is laminated to reduce copper loss. friction and windage loss. hysteresis loss. eddy current loss. copper loss. friction and windage loss. hysteresis loss. eddy current loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field weakening control method is used for the _________ ? both A and B above rated speed None of these below rated speed both A and B above rated speed None of these below rated speed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 200 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 Ω. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is 0.96 1.06 0.87 0.95 0.96 1.06 0.87 0.95 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines 1 KVA, 230 V, 50 Hz, single phase transformer has an eddy current loss of 30 watts. The eddy current loss when the transformer is excited by a dc source of same voltage will be less than 30 W more than 30 W zero watt 30 W less than 30 W more than 30 W zero watt 30 W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then E ∝ 1/(φf) E ∝ φf E ∝ f/φ E ∝ φ/f E ∝ 1/(φf) E ∝ φf E ∝ f/φ E ∝ φ/f ANSWER DOWNLOAD EXAMIANS APP