A 2,500kVA, three-phase, 60Hz, 6.6kV wye-connected alternator has a field resistance of 0.45 ohm and an armature resistance of 0.05ohm per phase. The field current at full load 0.85 pf, is 200A. The stray power losses amount to 82kW. Calculate the efficiency of the alternator at full load, 0.85 pf lagging

A 2,500kVA, three-phase, 60Hz, 6.6kV wye-connected alternator has a field resistance of 0.45 ohm and an armature resistance of 0.05ohm per phase. The field current at full load 0.85 pf, is 200A. The stray power losses amount to 82kW. Calculate the efficiency of the alternator at full load, 0.85 pf lagging

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.24P: A source supplies power to the following three loads connected in parallel: (1) a lighting load...

See similar textbooks

Similar questions

A source supplies power to the following three loads connected in parallel: (1) a lighting load drawing 10kW. (2) an induction motor drawing 10kVA at 0.90 power factor lagging, and (3) a synchronous motor operating at 10hp,85 effIciency and 0.95 power factor leading (1hp=0.746kW). Determine the real, reactive, and apparent power delivered by the source. Also, draw the source power triangle.
A 1500kVA, 3phase, 60Hz, 6.9kV, wye-connected alternator has a field resistance of 0.45Ω and an armature resistance of 0.05Ω per phase. The field current at full-load 0.8 pf is 200A. The stray power losses amount to 42kW. Calculate the efficiency of the alternator at full-load, 0.8 pf lagging.
A three-phase, 11kV, star-connected alternator delivers a current of 80A at (a)0.85 pf leading, (b) unity power factor, (c)0.7 power factor lagging. Full-load current of 80A is produced on short circuit by a field excitation of 2.9A. An emf of 400V per phase is produced on open circuit by the same excitation. The effective armature resistance is 0.85 ohm per phase. Determine the voltage regulation in each case.
A 50kVA, 550V single phase alternator draws a field current 10A at rated load. With the same field current, the open circuit emf and shirt circuit current are 300V and 150A. The ohmic resistance of the armature between terminals is 0.18Ω. The ratio of effective to ohmic resistance may be taken as 1.5. Determine the terminal voltage at 0.8 pf factor lagging. Use two decimal places.
A 15kVA, 440V, single-phase alternator draws a field current of 5A at rated load. With the same field current, the open circuit emf and short-circuit current are 100V and 80A respectively. The ohmic resistance of the armature between terminals is 0.12 ohm. The ratio of effective to ohmic resistance maybe taken as 1.1. Determine the voltage regulation (in %) when the load is purely resistive.
Two 300kVA, 1000V, 50Hz alternators operating in parallel to supply a load of 500KW at UPF. 60% of the load is supplied by the first generator. If the terminal voltage and power supplied are kept constant always, then changing the excitation to make pf=0.8 lagging. Find the generator currents, power factors and total load current. (the generator and load are single phase)
A 6.6 kV, 6 MVA, Y-connected, 3φ alternator has an effective ac resistance of 0.436Ω between terminals. The field current of 103A produces an open circuit emf of 6600V between terminals. The field current required to produce rated full-load current at short-circuit condition is 82A. What is the synchronous impedance per phase?
Kindly solve the problem with step by step complete solution. Also, put the given and formula used so that I can understand. Thank you. A 2200V, 60 Hz, three-phase, Y-connected alternator has an effective resistance per phase of 0.5 ohm. A field current of 30A produces a full load current of 200A on short circuit and a line-to-line emf of 1100 V on open circuit. Determine the power angle of the alternator when it delivers full load at .80 lagging pf.
A 1200 kVA, 6600 volt, 3-phase, Y-connected alternator has an effective resistance of 0.40 ohm and a reactance of 6 ohms per phase. It delivers full load current of 0.80 lagging power factor at rated voltage. What will be the terminal voltage for the same excitation and load current if the power factor is 0.80 leading? a. 4,560 V b. 9.878 V c. 7.898 V d. 4,250 V Choose the letter of the correct answer. Show your solution.
A 60kVA, 220V, 50Hz, single phase alternator has effective armature resistance of 0.016 ohm and an armature leakage reactance of 0.07 ohm. Compute the voltage induced when the alternator is delivering at a load power factor of (a) unity; a. 225.2V b. 252.2V c. 522.2V d. 222.5V
A 3 phase star-connected alternator is rated at 2,000 kVA, 13.5 kV. The armature effective resistance and XS are 1.3 ohms and 20 ohms respectively per phase. Calculate the percent regulation at full load for pf of o.8 lagging.
2. A 3Ø, 2000KW, 480V ∆-connected alternator is short-circuited and is operated at ratedspeed to produce rated current at 4A excitation. With the short-circuit remove andwith the excitation adjusted to 5A, the voltage between stator terminal is 330V. Theeffective resistance between terminal as measured with dc is 2Ω. Determine the %V.R.of the alternator at half-load and pf of 0.8 leading without changing any given values.