(c) A 2400 V, 1000 KVA, 0.85 power factor (PF) lagging, 50 Hz six-poles, Y-connected synchronous generator has a synchronous reactance of 1.4 2 and an armature resistance of 0.15 2. At 50 Hz, its friction and windage losses are 25 kW, and its core losses are 15 kW. The field circuit has a DC voltage of 230 V, and the maximum IF is 10 A. The resistance of the field circuit is adjustable over the range from 20 to 200 £2. The Open Circuit Characteristic (OCC) of this generator is shown in Figure Q1(c). Calculate the internal generated voltage, EA of this machine at rated conditions. (i) (ii) (iii) Determine the required field current to make Vr equal to 2400 V when the generator is running at rated conditions. If this machine is operating at rated conditions, determine the input torque, TApp that must be applied to the shaft of this generator.

(c) A 2400 V, 1000 KVA, 0.85 power factor (PF) lagging, 50 Hz six-poles, Y-connected synchronous generator has a synchronous reactance of 1.4 2 and an armature resistance of 0.15 2. At 50 Hz, its friction and windage losses are 25 kW, and its core losses are 15 kW. The field circuit has a DC voltage of 230 V, and the maximum IF is 10 A. The resistance of the field circuit is adjustable over the range from 20 to 200 £2. The Open Circuit Characteristic (OCC) of this generator is shown in Figure Q1(c). Calculate the internal generated voltage, EA of this machine at rated conditions. (i) (ii) (iii) Determine the required field current to make Vr equal to 2400 V when the generator is running at rated conditions. If this machine is operating at rated conditions, determine the input torque, TApp that must be applied to the shaft of this generator.

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

Chapter6: Power Flows

Section: Chapter Questions

Problem 6.48P

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