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AC Generator
dristyBD EEE MCQ
An electric generator, or dynamo, is a machine which converts mechanical energy into electrical energy.
Test Your Knowledge About AC Generator
- The frequency of alternator having 4-poles and rotating speed at 1500 rpm is ----Hz
- A 50 Hz alternator will run at the greatest possible speed if it is wound for.....poles.
- The winding of a 4-pole alternator having 36 slots and coil span of 1 to 8 is short pitched by....degrees.
- If an alternator winding has a fractional pitch of 5/6 , the coil span is.....degrees.
- When speed change of an alternator is changed from 3600 rpm to 1800 rpm, the generated voltage/phase will become-
twice one-half one fourth none of above
- Armature reaction in an alternator primarily affects
frequency of armature current generated voltage per phase roto speed none of above
- Under no load condition , power drawn by the prime mover of an alternator goes to
meet no-load losses produce power in armature meet cu losses meet induced emf in armature winding
- The power factor of an alternator is determined by its--
speed excitation load none of above
- Condition of parallel operation of alternator--
voltage rating same frequency smae phase sequence same all of above
- Two identical alternator are running in parallel and carry equal loads. If excitation of one alternator is increased without changing its fuel supply, then
KVA decrease it will keep supplying almost same load its p.f will increase none of above
- For a machine on infinite bus active power can be varied by--
changing of prim mover speed changing field excitation both A and B none of above
- Squirrel cage bars placed in the roto pole facts of an alternator help reduce hunting
above synchronus speed above and below synchronus speed Below synchronus speed none of above
- The load sharing between two steam drivenalternator operating in parallel may be adjusted by varying the..
field strength of the alternator p.f of the alternator steam supply to ther prime mover all of above
- Can d.c generator converted into an alternator?
no yes
- Which is alternator rating--
KVA
KW
HP
KVA
Ans:-
- D
- A
- C
- B
- B
- B
- A
- B
- C
- B
- D
- B
- A
- D
- B
- A
- B
- C
- B
- A
