and armature resistance of 0.5 Ω. At 60 Hz, the total mechanical losses are 2 MW. The no-load saturation curve giving the relationship between output phase voltage, Eo and excitation current Ix is shown in the picture. If the excitation is adjusted so that the terminal line voltage remains fixed at 24.25 kV, calculate the following: (i) Exciting field current required at no-load. (ii) Required exciting field current for 20 MW of connected load with 0.8 power factor lagging (iii) Efficiency of the generator at condition (ii) (iv) Input torque of generator (v) Explain why this kind of electrical machine commonly used in power generation?

and armature resistance of 0.5 Ω. At 60 Hz, the total mechanical losses are 2 MW. The no-load saturation curve giving the relationship between output phase voltage, Eo and excitation current Ix is shown in the picture. If the excitation is adjusted so that the terminal line voltage remains fixed at 24.25 kV, calculate the following: (i) Exciting field current required at no-load. (ii) Required exciting field current for 20 MW of connected load with 0.8 power factor lagging (iii) Efficiency of the generator at condition (ii) (iv) Input torque of generator (v) Explain why this kind of electrical machine commonly used in power generation?

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 3.30P: Reconsider Problem 3.29. If Va,VbandVc are a negative-sequence set, how would the voltage and...

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