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

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

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 2.41P

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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
An industrial plant consisting primarily of induction motor loads absorbs 500 kW at 0.6 power factor lagging. (a) Compute the required kVA rating of a shunt capacitor to improve the power factor to 0.9 lagging. (b) Calculate the resulting power factor if a synchronous motor rated at 500 hp with 90 efficiency operating at rated load and at unity power factor is added to the plant instead of the capacitor. Assume constant voltage (1hp=0.746kW).
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