railway UPMRC SCTO 2024 Mock Test Electrical Machines Alternator and Synchronous Motors Effect of Excitation on Armature Current and Power Factor
Consider the following statements with respect to synchronous machines. State whether these statements are true or false.
(a) Armature reaction is demagnetising when a generating machine supplies zero power factor lagging current.
(b) Armature reaction is magnetising when a generating machine supplies zero power factor leading current.
(c) Armature reaction is mostly cross-magnetising, though it has a small demagnetising component, when a generating machine supplies unity power factor current.
1
(a) False, (b) True and (c) False
2
(a) True, (b) True and (c) True
3
(a) False, (b) True and (c) True
4
(a) True, (b) True and (c) False