Completely solve and box the final answer. Write legibly A 1200 kVA, 6600 volts, 3-phase Y connected alternator, has an effective resistance of 0.4 ohms and a reactance of 6 ohms per phase. It delivers full load current at 0.8 lagging power factor at rated voltage. What will be the terminal voltage for the same excitation and load current, if the power factor is 0.8 leading? Show the phasor diagram. [ Ans. 7899 V ]

Completely solve and box the final answer. Write legibly A 1200 kVA, 6600 volts, 3-phase Y connected alternator, has an effective resistance of 0.4 ohms and a reactance of 6 ohms per phase. It delivers full load current at 0.8 lagging power factor at rated voltage. What will be the terminal voltage for the same excitation and load current, if the power factor is 0.8 leading? Show the phasor diagram. [ Ans. 7899 V ]

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

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.56P: Three single-phase two-winding transformers, each rated 3kVA,220/110volts,60Hz, with a 0.10 per-unit...

See similar textbooks

Similar questions

A 1200 kVA, 6600 volts, 3-phase Y connected alternator, has an effective resistance of 0.4 ohms and a reactance of 6 ohms per phase. It delivers full load current at 0.8 lagging power factor at rated voltage. What will be the terminal voltage for the same excitation and load current, if the power factor is 0.8 leading? Ans.: 4560.22 volts per phase show circuit diagram
The effective resistance of a 2200 V, 50 Hz, 440 KVA, 1 -phase alternator is 0.5 ohm. On short-circuit, a field current of 40 A gives the full load current of 200 AS. The electromotive force on open-circuits with same field excitation is 1160 V. Then the synchronous impedance and reactance is _______ ohm and _______ ohm respectively.
A three-phase alternator of 4 poles and 60 HZ, connected in star of 100 KVA and 1100 volts is tested for OCC, SCC and winding resistance, giving the following data: Based on the above data, obtain: a) - The equivalent circuit per phase of the alternator b) - Operating speed c) - If it is synchronized with a power system whose frequency is 60 Hz and the alternator has a Sp=5 kW/Hz and its speed at the moment of synchronization is 1860 rpm, what power will it deliver? d) - What will be your internal voltage generated if you feed a load with forward PF of 0.9 and you are at 80% of your load? e) - For the case of item d), what is the reactive power delivered or consumed?
A three-phase Y-connected alternator delivers a unity power-factor load at 230 volts. If the synchronous-reactance voltage drop is 60 volts per phase, calculate the per cent regulation, neglecting the resistance voltage drop.Ans.: 9.77%
A 3-Phase 10Kva, 400 V, 50Hz star connected alternator supplies a rated load at 0.8 power factor lagging. If the armature resistance per phase is 0.5Ჲ and the synchronous reactance is 10Ჲ, using the e.m.f method, estimate the alternator’s voltage regulation
Two 50-MVA, 3-phase alternators operate in parallel. The settings of the governors are such that the rise in speed from full-load to no-load is 2 percent in one machine and 3 percent in the other, the characteristics being straight lines in both cases. If each machine is fully loaded when the total load is 100 MW, what would be the load on each machine when the total load is 60 MW? (Req'd) Draw an appropriate diagram.
Two identical three-phase Alternators A and B share equally a load of 10 MVA at 33 KV and 80% lagging power factor. The synchronous reactance of each generator is 4 ohms per phase and the armature resistance is negligible. Alternator A has its field excitation adjusted to carry a25 amperes at lagging power factor. What is the current delivered by Alternator B ?
19.In a 3-phase star-connected alternator, a field current of 40 A produces a full load current of 200 A on short circuit and 1160 volt on open circuit. If the resistance of the alternator per phase is 0.50 ohm, then the value of the synchronous reactance is
A three-phase Y-connected alternator delivers a unity power-factor load at 220 volts. If the synchronous-reactance voltage drop is 50 volts per phase, neglecting the resistance voltage drop. a. calculate the generated voltage b. calculate the percent regulation
A 3,000-kw 750-volt d-c 60-cycle six-phase synchronous converter is fed from a three-phase 23,000-volt high-voltage line through &bank of three transformers that are connected in Δ on the high side and diametrical on the low side. (A) Make a winding diagram showing all connections for the problem. Assuming an efficiency and power factor of 96percent and 0.95, respectively, calculate: (B) the direct-current output; (C) the a-c voltage between adjacent slip rings.
An 11 kV, three-phase, turbo alternator has a synchronous impedance per phase of(0,4 + j0,8) Ω and it supplies 2 kA at unity power factor to an infinite bus. Theexcitation is increased so that the emf is increased by 20%. Sketch a general loaddiagram and determine the following from this diagram: the armature current for maximum power output, the actual maximum power output
A three-phase, 318.75 kVA, 2300 V alternator has an armature resistance of 0.35 ohms/phase and a synchronous reactance of 1.2 ohms/phase. Determine the voltage regulation at full-load kVA, 0.8 power factor lagging and rated voltage.