Q1. The following data refer to the O.C.C of a D.C separately excited generator at 1000 rpm. Field current in A 0.2 0.4 0.6 0.8 1 1.2 Amature voltage in V 75 100 145 178 195 204 The machine is now connected as a shunt generator with a total field resistance of 200 2 and driven at 1000 rpm. Estimate graphically: (i) the voltage to which the generat or will build up at no load. (ii) the armature, field and load currents when the teminal voltage is found to be 150 V. Neglect the effect of armature reaction and brush drop and assume armature resistance Rato be 0.8 2. (iii) Finally estimate the steady state armature current when the machine terminals are shorted.

Q1. The following data refer to the O.C.C of a D.C separately excited generator at 1000 rpm. Field current in A 0.2 0.4 0.6 0.8 1 1.2 Amature voltage in V 75 100 145 178 195 204 The machine is now connected as a shunt generator with a total field resistance of 200 2 and driven at 1000 rpm. Estimate graphically: (i) the voltage to which the generat or will build up at no load. (ii) the armature, field and load currents when the teminal voltage is found to be 150 V. Neglect the effect of armature reaction and brush drop and assume armature resistance Rato be 0.8 2. (iii) Finally estimate the steady state armature current when the machine terminals are shorted.

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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