Electrical Machines A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by changing the field excitation. varying the applied voltage. changing the load. varying the speed. changing the field excitation. varying the applied voltage. changing the load. varying the speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The oscillation in a synchronous motor can be damped out by maintaining constant excitation. providing damper bars in the rotor pole faces. running the motor on leading power factors. oscillation cannot be damped. maintaining constant excitation. providing damper bars in the rotor pole faces. running the motor on leading power factors. oscillation cannot be damped. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Open circuit test on transformer gives copper loss both 1and 2 eddy current loss hysteresis loss copper loss both 1and 2 eddy current loss hysteresis loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An inverted V curve of synchronous motor shows variation of supply voltage and excitation current at constant load. power factor and DC excitation at constant load. supply voltage and field current at constant excitation. power factor and supply voltage during hunting. supply voltage and excitation current at constant load. power factor and DC excitation at constant load. supply voltage and field current at constant excitation. power factor and supply voltage during hunting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In field flux method speed control of DC Motor is constant hp drive below the base speed. constant torque drive above the base speed. constant torque drive below the base speed. constant power drive above base speed. constant hp drive below the base speed. constant torque drive above the base speed. constant torque drive below the base speed. constant power drive above base speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are effects of armature reaction? increase the maintenance and repair increase the iron loss increases the design cost All of these increase the maintenance and repair increase the iron loss increases the design cost All of these ANSWER DOWNLOAD EXAMIANS APP