By which of the following methods motor rating for variable load drives can be determined ?
A. Method of average losses
B. Equivalent current method
C. Equivalent torque method
D. Equivalent power method
E. All of the above
A. Method of average losses
B. Equivalent current method
C. Equivalent torque method
D. Equivalent power method
E. All of the above
A. Total m.m.f. required
B. The number of turns in the exciting winding
C. The way in which the winding is distributed
D. All of the above
A. Thermometer method
B. Resistance method
C. Embedded temperature detector method
D. Any of the above
A. One sided axial ventilation
B. Two sided axial ventilation
C. Multiple inlet system
D. All of the above
Which of the following methods is used for air cooling of turbo-alternators ? Read More »
Electrical Machine Design A. The current in the slot conductors is uniformly distributed over their cross-section
B. The leakage path is straight across the slot and around the iron at the bottom
C. The permanence of air paths is only considered. The reluctance of iron paths is assumed as zero
D. All of the above
The slot leakage can be calculated by making which of the following assumptions ? Read More »
Electrical Machine Design A. Equivalent power method
B. Equivalent current method
C. Method of average losses
D. Equivalent torque method
A. heating time constant
B. cooling time constant
C. either A. or B.
D. none of the above
A. 200 MW
B. 300 MW
C. 400 MW
D. 600 MW
With direct water cooling it is possible to have ratings of about_____________? Read More »
Electrical Machine Design A. 2 to 3 times greater
B. 3 to 4 times greater
C. 4 to 5 times greater
D. none of the above
A. no mechanical difficulties
B. lesser mechanical difficulties
C. greater mechanical difficulties
D. none of the above
Direct water cooling of rotor winding presents_____________? Read More »
Electrical Machine Design