Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 50 Hz 100 Hz 25 Hz 0 Hz 50 Hz 100 Hz 25 Hz 0 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The functions of inter poles are nullify reactance voltage and improve the commutation. None of these both 1 and 2 reduce cross magnetization effect and improve commutation nullify reactance voltage and improve the commutation. None of these both 1 and 2 reduce cross magnetization effect and improve commutation ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To have sparkless commutation, the armature reaction effect in a DC machine is neutralized by increasing field excitation. shifting the brush axis from GNA to MNA. compensating winding and commutating poles. fixing the brush axis inline with the pole axis. increasing field excitation. shifting the brush axis from GNA to MNA. compensating winding and commutating poles. fixing the brush axis inline with the pole axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A simple method of increasing the voltage of a DC generator is to increase the source frequency. increase the number of turns in armature coil. increase the number of turns in field coil. increase the speed of shaft rotation. increase the source frequency. increase the number of turns in armature coil. increase the number of turns in field coil. increase the speed of shaft rotation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : For a level compounded dc generator to run at constant voltage, the series field mmf must effectively compensate 1. armature reaction mmf 2.armature resistance drop 3. brush contact voltage drop Which of these statements is/are correct ? 1, 2 and 3 1 and 2 2 alone 1 and 3 1, 2 and 3 1 and 2 2 alone 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following rotor requires damper winding? Both type rotor. Cylindrical rotor. Salient pole rotor. None of these Both type rotor. Cylindrical rotor. Salient pole rotor. None of these ANSWER DOWNLOAD EXAMIANS APP