a delta connected, round rotor 3-phase synchronous generator with mains phase voltage V1L= 400 V: Ef= 2*V1, Ra negligible, Xs=10 Ohm, Mechanical losses negligible, current value of load angle is 20 degrees (initial case) . The machine works in parallel with the mains. In the new case, the generator's driving torque is being modified. Keeping the above given, the new value of the load angle becomes 3 times its initial value. Which of the following is the ratio of the generator driving torque in the new state to the driving torque in the original state? a) 0.395 b) 2.532 c) 4.596 d) -1.815 e) 4.386 f) -0.605 g) 7.596

a delta connected, round rotor 3-phase synchronous generator with mains phase voltage V1L= 400 V: Ef= 2*V1, Ra negligible, Xs=10 Ohm, Mechanical losses negligible, current value of load angle is 20 degrees (initial case) . The machine works in parallel with the mains. In the new case, the generator's driving torque is being modified. Keeping the above given, the new value of the load angle becomes 3 times its initial value. Which of the following is the ratio of the generator driving torque in the new state to the driving torque in the original state? a) 0.395 b) 2.532 c) 4.596 d) -1.815 e) 4.386 f) -0.605 g) 7.596

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

Chapter11: Transient Stability

Section: Chapter Questions

Problem 11.3P

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