Electric Machine Daily Quiz #18

1 pu field current is the current at which-

1. The armature current becomes rated or 1 pu
2. The speed becomes synchronous
3. The voltage across armature wdg becomes rated or 1 pu
4. The OCC becomes linear

The relation between SCR (short circuit ratio) and per unit synchronous reactance of saturated machine Xsat is-

1. SCR = Xsat
2. SCR = 1/Xsat
3. SCR = (Xsat)^2
4. SCR = (Xsat)^(1/2)

Line charging capability is given by-

1. -(V)^2  x SCR
2. -(V)^2  /SCR
3. -V x SCR
4. -V /SCR

Potier Characteristics is

1. Variation of terminal voltage against field current when armature current is maintained at rated value and at Zero pf lag
2. Variation of terminal voltage against field current when armature current is maintained at rated value and at Zero pf lead
3. Variation of terminal voltage against field current when armature current is maintained at rated value and at Unity pf
4. None

Which of the following method of calculating voltage regulation of a synchronous machine is also called PESSIMISTIC METHOD?

1. EMF method
2. MMF method
3. ZPF/ Potier method
4. ASA method