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 2. Find (a) effective armature resistance (b) synchronous reactance (c) the full-load voltage regulation at 0.8 p.f. lagging. (Ans. (a) 0.3092/phase (b) 3.312 (c) 49.6%)

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 2. Find (a) effective armature resistance (b) synchronous reactance (c) the full-load voltage regulation at 0.8 p.f. lagging. (Ans. (a) 0.3092/phase (b) 3.312 (c) 49.6%)

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

See similar textbooks

Similar questions

Two identical 2,000 kW alternator operates in parallel. The governor of the first machine is such that the frequency drops uniformly from 50 Hz at no-load to 48 Hz at full-load. The corresponding uniform speed drop of the second machine is 50 Hz to 47.5 Hz. What is the maximum load that can be delivered without overloading either machine?
1. A3-phase, star-connected alternator is rated at 15000 kVA, 11 kV. The armature resistance is I-5 S/phase and synchronous reactance is 300/phase. To what value will the terminal voltage rise when full-load at p.f. 0-8 lagging is switched off? [13970 V]
Why brushless exciters are used in a synchronous generators. If two parallel alternators’ have different phase sequences, explain the consequences that may happen.
A 550 volts, 55KVA single phase alternator has an effective resistance of 0.02 ohms, a fieldresistance of 10 ohms produces an armature current of 200 A on short circuit and an EMF of 450volts on open circuit. What is the voltage regulation at full load and 0.80 lagging power factor
what is a difference between AC AND DC load line
A 50 KVA, 550 Volt single phase alternator draws a field current 10 A at rated load. With the same field current, the open circuit emf and short circuit current are 300 V and 150A. The ohmic resistance of the armature between terminals is 0.18 ohm. The ratio of effective to ohmic resistance maybe taken as 1.5. Determine the regulation at 0.8 power factor lagging. 583
What are the main effects of losses on the performance of the alternator?
The open circuit voltage is 14,000 volts of a 12,000 volts three- phase wye-connected turbo alternator with synchronous reactance of 5 ohms and a negligible resistance per phase. When the field current is 7A, determine the a. maximum power developed b. armature current when it developed maximum power
In a Three-phase alternator, a given field current produces an armature current of 250 A on short-circuit and a generated e.m.f. of 1500 V on open-circuit. Calculate the terminal p.d. when a load of 250 A at 6.6 kV and 0.8 p.f. lagging is switched off. Calculate also the regulation of the alternator at the given load. Subject: Electrical engineering
What is the basic principle of alternators?
I need the answer as soon as possible
9.a. If a 33% load increase is suddenly applied to an alternator having a 25% reactance, the initial voltagedrop will be aboutA. 8.25%B. 13.25%C. 3.3%D. 2.5%9.b. At what speed must a four-pole alternator operate to produce a 100-cps alternating voltage?A. 3000 rpmB. 12,000 rpmC. 1500 rpmD. 6000 rpm