A cylindrical rotor synchronous generator with constant real power output and constant terminal voltage is supplying 100 A current to a 0.9 lagging power factor load. An ideal reactor is now connected in parallel with the load, as a result of which the total lagging reactive power requirement of the load is twice the previous value while the real power remains unchanged. The armature current is now A. Ans. 125.34 A

A cylindrical rotor synchronous generator with constant real power output and constant terminal voltage is supplying 100 A current to a 0.9 lagging power factor load. An ideal reactor is now connected in parallel with the load, as a result of which the total lagging reactive power requirement of the load is twice the previous value while the real power remains unchanged. The armature current is now A. Ans. 125.34 A

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 2.16P: A single-phase, 120V(rms),60Hz source supplies power to a series R-L circuit consisting of R=10 and...

See similar textbooks

Similar questions

While the instantaneous electric power delivered by a single-phase generator under balanced steady-state conditions is a function of time havi ng two components of a constant and a double-frequency sinusoid, the total instantaneous electric power delivered by a three-phase generator under balanced steady-state conditions is a constant. (a) True (b) False
A single-phase, 120V(rms),60Hz source supplies power to a series R-L circuit consisting of R=10 and L=40mH. (a) Determine the power factor of the circuit and state whether it is lagging or leading. (b) Determine the real and reactive power absorbed by the load. (c) Calculate the peak magnetic energy Wint stored in the inductor by using the expression Wint=L(Irms)2 and check whether the reactive power Q=Wint is satisfied. (Note: The instantaneous magnetic energy storage fluctuates between zero and the peak energy. This energy must be sent twice each cycle to the load from the source by means of reactive power flows.)
The voltage v(t)=359.3cos(t)volts is applied to a load consisting of a 10 resistor in parallel with a capacitive reactance XC=25. Calculate (a) the instantaneous power absorbed by the resistor, (b) the instantaneous power absorbed by the capacitor. (c) the real power absorbed by the resistor, (d) the reactive power delivered by the capacitor, and (e) the load power factor.
Consider a 3-phase delta induction motor that is operating at 120 Hz. The motor (load) impedance, Z_Δ is given as (9+j12)Ω. The line-to-line voltage at the load is, ?_ab=416 ∠30ºVrms. Let the source be wye-connected, and line impedance be negligible. a) Draw the single-phase wye equivalent circuit and label all known parameters numericallyincluding load voltage. b)Determine the rms phase current phasors for each phase. c) Calculate the complex power consumed by the 3-phase load. d) Determine the capacitance value of each capacitor in a 3-phase delta capacitor bank needed to correct the load to a power-factor of 0.9, lagging.
Consider a 3-phase delta induction motor that is operating at 120 Hz. The motor (load) impedance, Z_Δ is given as (9+j12)Ω. The line-to-line voltage at the load is, ?_ab=416 ∠30ºVrms. Let the source be wye-connected, and line impedance be negligible. b)Determine the rms phase current phasors for each phase. c) Calculate the complex power consumed by the 3-phase load. d) Determine the capacitance value of each capacitor in a 3-phase delta capacitor bank needed to correct the load to a power-factor of 0.9, lagging.
Two alternators rated 400 MW and 600 MW are operating in parallel. The droop characteristics of their governors are 3% and 4% respectively from no load to full load. Assuming that the alternators are operating at 50 Hz at no load, how would a load of 1000 MW be shared between them? What will be the system frequency at this load? [Ans. G1 = 468.132 MW, G2 = 531.669 MW, f= 48.296 Hz]
An 11 kV, three-phase, star-connected alternator has a synchronous impedance of10∟80° Ω/phase and operates at unity power factor on infinite bus bars. It supplies acurrent of 300 A by using a general load diagram. Determine: the full-load current for normal excitation ( motor mode), the current and power factor for 100% excitation on 25% overload (generatormode), the maximum power that the machine can develop in the generator mode for50% excitation
a) How many MVAr of shunt capacitors are required to increase the power factor on a 10 MVA load from 0.85 to 0.9 lagging? b) How many MVAr of shunt capacitors are required to increase the power factor on a 10 MVA load from 0.90- to 0.95 lagging? c) Which requires more reactive power, improving a low power-factor load (case a) or a high power-factor load (case b)?
A 13.8-kV, single-phase generator supplies power to a load through a step-up transformer, a transmisson line, and a step-down transformer as in the figure above. Assume the transformers are ideal. The load’s impedance is Zload = 200 L 36.870, and the transmission line’s impedance is Zline = 70 L 600 What are the transmision losses in Watts?
Pls. Answer thank you! A generating station has a maximum demand of 25MW, a load factor of 60%, a plant capacity factor of 50% and a plant use factor of 72%. Find the reserve capacity of the plant in MW.
A power plant comprises three turbine-generators rated 1000 MW, 800 MW and 600 MW respectively. The regulation constant of each generator is 0.05 pu based on its own rating. Each unit is initially operating at one-half of its own rating, when the system load suddenly increases by 250 MW. Calculate the following:a) Per-unit area frequency response characteristic on a 1000 MW system base [CR9]b) Steady-state drop in area frequency [CR4]c) The share of the load increase on each generator [CR9]d) Total load on each generator after the increase in system load [CR3]Assume the reference power setting of each turbine is unchanged.
synchronous generator operating under steady conditions supplying a load current I0to the bus at a terminal voltage of V0. E, is the induced emf under loaded condition and Xa is the direct axis synchronous reactance of the machine. Draw the equivalent circuit model of the system.