Q2 (a) Indicate any changes in a stand alone synchronous generators performance or operating limits for the following changes to the generator design or operation: (i) A reduction in the synchronous reactance. (ii) An increase in generator speed. (iii) An increase in the rotor current. (iv) An increase in the number of turns in the stator windings. A star connected 3 phase wound field synchronous generator (Xs=4 2) operates with a 15 kV Excitation voltage at a load angle of 3GS° and is connected to a 11 kV (phase voltage) grid. Using a combination of calculation and scaled phasor diagram determine the resultant line current (A), power factor and total output power (W). Draw the resultant phasor diagram to scale including the resultant line current. (b) The load power is now halved with the Excitation voltage kept constant. Using the phasor diagram drawn in Q2(b) graphically determine the new line current, power factor and load angle. (c) Calculate the maximum theoretical output power for this given Excitation voltage and grid phase voltage. (d)

Q2 (a) Indicate any changes in a stand alone synchronous generators performance or operating limits for the following changes to the generator design or operation: (i) A reduction in the synchronous reactance. (ii) An increase in generator speed. (iii) An increase in the rotor current. (iv) An increase in the number of turns in the stator windings. A star connected 3 phase wound field synchronous generator (Xs=4 2) operates with a 15 kV Excitation voltage at a load angle of 3GS° and is connected to a 11 kV (phase voltage) grid. Using a combination of calculation and scaled phasor diagram determine the resultant line current (A), power factor and total output power (W). Draw the resultant phasor diagram to scale including the resultant line current. (b) The load power is now halved with the Excitation voltage kept constant. Using the phasor diagram drawn in Q2(b) graphically determine the new line current, power factor and load angle. (c) Calculate the maximum theoretical output power for this given Excitation voltage and grid phase voltage. (d)

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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