Electrical Machines A dc shunt motor has external resistance Ra and Rf in the armature and field circuits respectively. Armature current at starting can be reduced by keeping Rf maximum and Ra minimum Ra maximum and Rf minimum Ra minimum and Rf minimum Ra maximum and Rf maximum Rf maximum and Ra minimum Ra maximum and Rf minimum Ra minimum and Rf minimum Ra maximum and Rf maximum ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two 3-phase AC generators are such that one has twice the linear dimensions of the other. The field windings of each are excited to give identical sinusoidal air-gap flux density waveform. Both have the same number of stator slots and identical winding patterns. The conductor/slot in a big generator is K times that of the smaller one. The value of K to get equal no load voltage at same frequency is 1/4. 8. 4. 1/2. 1/4. 8. 4. 1/2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following, voltage regulation may be zero or negative leading power factor unity power factor All of these lagging power factor leading power factor unity power factor All of these lagging power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cross magnetization effects which of the following? both 2 and 3 reduces the terminal voltage commutation reduction in main field flux both 2 and 3 reduces the terminal voltage commutation reduction in main field flux ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The interpoles in dc machines have a tapering shape in order to increase the acceleration of commutation economise on the material required for interpoles and their windings reduce the saturation in the interpole reduce the overall weight increase the acceleration of commutation economise on the material required for interpoles and their windings reduce the saturation in the interpole reduce the overall weight ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a compensated DC series motor, the compensating winding is provided In series with the armature winding. In parallel with the armature winding. In parallel with the field winding. As a separate unit. In series with the armature winding. In parallel with the armature winding. In parallel with the field winding. As a separate unit. ANSWER DOWNLOAD EXAMIANS APP
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