Electrical Machines The volt-ampere euation for a long-shunt compound motor is given by Vt= Ea– Iara Vt = Ea + Iara+ ILrs Vt = Ea + Ia(ra + rs) Vt= Ea + Iara Vt= Ea– Iara Vt = Ea + Iara+ ILrs Vt = Ea + Ia(ra + rs) Vt= Ea + Iara 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 ∝ φf E ∝ φ/f E ∝ 1/(φf) E ∝ f/φ E ∝ φf E ∝ φ/f E ∝ 1/(φf) E ∝ f/φ ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To eliminate the 5th harmonic in the induced voltages their respective pitch factor angle should be 30° 18° 72° 36° 30° 18° 72° 36° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is/are the necessary conditions for parallel operation of alternators? Terminal voltage is same Frequency should be same Speed of alternators should be same Both 1and 2 Terminal voltage is same Frequency should be same Speed of alternators should be same Both 1and 2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If in DC Shunt Motor the flux is reduced suddenly to zero, then the armature current will reduce. the motor will come to stop. the speed of motor will be reduced. the motor will attain dangerously high speed. the armature current will reduce. the motor will come to stop. the speed of motor will be reduced. the motor will attain dangerously high speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In large sized DC machines the compensating windings are provided to reduce eddy current losses by providing local short circuits. compensate for the decrease in speed due to increase of load. None of these neutralize voltage induced in coil due to fluctuation of l reduce eddy current losses by providing local short circuits. compensate for the decrease in speed due to increase of load. None of these neutralize voltage induced in coil due to fluctuation of l ANSWER DOWNLOAD EXAMIANS APP
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