The following table gives the open-circuit voltages for different field currents of a shunt generator driven at a constant speed: Terminal voltage (V) Field current (A) 120 _240 _334 _400 _444 _470 B_0-5 1-0 1-5 2:0 2-5 3-0 Plot a graph showing the variation of generated e.m.f. with exciting current and from this graph derive the value of the generated e.m.I. When the shunt circuit has a resistance of (a) 160 n, (b) 210 2 and (C) S00 12, Also find the yalue of the critical resistance of the shunt circuit. 300 N, Also find the value of the critical resistance of the shunt circuit.5. The following table gives the open-circuit voltages for different fieldcurrents of a shunt generator driven at a constant speed:Terminal voltage (V)Field current (A)120 240 334 400 444 4700-5 1-0 1-5 2:0 2-5 3-0Plot a graph showing the variation of generated e.m.f. with excitingcurrent and from this graph deriye the value of the generated e.m.f.when the shunt circuit has a resistance of (a) 160n, (b) 210 2 ana (e)

The graph for generated electromotive force and exciting current: a) In this graph draw a line of…

The following table gives the open-circuit voltages for different field currents of a shunt generator driven at a constant speed: Terminal voltage (V) Field current (A) 120 240 334 400 444 470 0.5 1-0 1-5 20 2-5 3-0 Plot a graph showing the variation of generated e.m.f. with exciting current and from this graph derive the value of the generated e.m.I. When the shunt circuit has a resistance of (a) 160 Q, (b) 210 2 and (c) 300 2, Also find the value of the critical resistance of the shunt circuit.

The following table gives the open-circuit voltages for different field currents of a shunt generator driven at a constant speed: Terminal voltage (V) Field current (A) 120 240 334 400 444 470 0.5 1-0 1-5 20 2-5 3-0 Plot a graph showing the variation of generated e.m.f. with exciting current and from this graph derive the value of the generated e.m.I. When the shunt circuit has a resistance of (a) 160 Q, (b) 210 2 and (c) 300 2, Also find the value of the critical resistance of the shunt circuit.

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

Chapter6: Power Flows

Section: Chapter Questions

Problem 6.48P

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N K © M =] v : @& docs.google.com/forms/d/¢ 2 Add file Q 1/ B) What is the work of Commutator . * &2, Add file Q 2) The following information is given for a 300-kW, 600-V, long-shunt compound generator : Shunt field resistance = 75 Q, armature resistance including brush resistance = 0.03 Q, commutating field winding resistance = 0.011Q, series field resistance = 0.012 Q, diverter resistance = 0.036 Q. When the machine is delivering full load, calculate the voltage and power generated by the armature * 2 Add file Q 3) A four pole aenerator havina - >
A 4-pole, 250V, 120kW, DC short shunt compound generator has the following parameters: Ra=0.015 Ω, Rse=0.01 Ω, Rf =125 Ω, flux per pole=3x10^6 maxwells, Speed=1000rpm, hysteresis loss=2.5kW, eddy current loss=1.5kW, total mechanical loss=5kW. At what speed and excitation does this generator needs to operate in order to maintain an overall efficiency of 88%. Note: Excitation needs to be adjusted with speed in order to generate the same emf.
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