Two identical generators 5MVA, 6.6KV equally sharing a load of 8 MW at 6.6kV, 0.8 lagging p.f. The ractanctance between the internal voltage of each machine and the load bus is 2 pu. Both machines are equally excited. (a) Find the excitation emf for both machines. (b) If the excitation emf for machine-1 is increasesd by 20%, find the percentage change in Ea2 to keep the terminal voltage unchanged. Assume that the governor setting for both machine to remain unchanged.

Two identical generators 5MVA, 6.6KV equally sharing a load of 8 MW at 6.6kV, 0.8 lagging p.f. The ractanctance between the internal voltage of each machine and the load bus is 2 pu. Both machines are equally excited. (a) Find the excitation emf for both machines. (b) If the excitation emf for machine-1 is increasesd by 20%, find the percentage change in Ea2 to keep the terminal voltage unchanged. Assume that the governor setting for both machine to remain unchanged.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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(i) A chopper circuit drives an inductive load from 360 DC supply. Given the load resistance as 8 2, the average load current as 20 A and operating frequency is 480 Hz. When the chopper is ON, 7 V is dropped. Calculate (a) conduction period (in milliseconds) (b) blocking period of the chopper (in milliseconds) (c) duty cycle of the chopper (d) draw the ON and OFF time period waveform (ii) Draw the circuit diagram of the single phase bridge rectifier which is used in two quadrant operation (RL load) and explain its operation. · Duty Cycle ON period OFF period
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