Question

'5. A 3-phase, 50 Hz, star-connected, 1000 KVA, 2300V alternator gives a short-circuit current of 400 A for a certain field excitation. With the same excitation, the open-circuit voltage was 1328 V (phase value). The d.c. resistance between two lines is 0.412 Q. Find effective armature resistance (b) synchronous reactance (c) the full-load voltage regulation at 0.8 p.f: lagging: (Ans. 0.309@/phase (b) 3.319 (c) 49.6%'

Name: 5 a 3 phase 50 hz star connected 1000 kva 2300v alternator gives a short circuit current of 400 a for a certain field excitation with the same excitation the open circuit voltage was 1328 v 24996
Uploaded: 2022-01-09T13:49:39-08:00
Duration: 2 min 21 s
Channel: Prem Bijarniya
Description: 5 a 3 phase 50 hz star connected 1000 kva 2300v alternator gives a short circuit current of 400 a for a certain field excitation with the same excitation the open circuit voltage was 1328 v 24996

          '5. A 3-phase, 50 Hz, star-connected, 1000 KVA, 2300V alternator gives a short-circuit current of 400 A for a certain field excitation. With the same excitation, the open-circuit voltage was 1328 V (phase value). The d.c. resistance between two lines is 0.412 Q. Find effective armature resistance (b) synchronous reactance (c) the full-load voltage regulation at 0.8 p.f: lagging: (Ans. 0.309@/phase (b) 3.319 (c) 49.6%'

Added by Jason L.

University Physics with Modern Physics

Hugh D. Young 14th Edition

Instant Answer

Solved by Expert Prem Bijarniya

01/09/2022

Step 1

412/√3 = 0.238 Ω/phase But, the resistance per phase is always half of the line resistance in a star connection. So, the effective armature resistance is: Ra = 0.238/2 = 0.119 Ω/phase Show more…

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'5. A 3-phase, 50 Hz, star-connected, 1000 KVA, 2300V alternator gives a short-circuit current of 400 A for a certain field excitation. With the same excitation, the open-circuit voltage was 1328 V (phase value). The d.c. resistance between two lines is 0.412 Q. Find effective armature resistance (b) synchronous reactance (c) the full-load voltage regulation at 0.8 p.f: lagging: (Ans. 0.309@/phase (b) 3.319 (c) 49.6%'