A 400 V, 3-phase alternator is subjected to an unsymmetrical fault. Thesequence currents are Ia1= -j10 A, Ia2 = j6 A and Iao = j4 A. The sequenceimpedances are Z1 = j10 ohm, Z2 = j5 ohm and z0 = j7.5 ohm. Find thefault current and the type of fault. Also find the terminal voltages (phase andline) of the generator.

Ia=Ia0+Ia1+Ia2Ia=-j10+j6+j4=0Therefore , it is Double line to ground fault Fault current is -…

Answered: A 400 V, 3-phase alternator is…

Engineering

Electrical Engineering

A 400 V, 3-phase alternator is subjected to an unsymmetrical fault. The

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter7: Alternating Current, Power Distribution, And Voltage Systems

Section: Chapter Questions

Problem 7RQ

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Concept explainers

Single Phase Induction Motor

The single-phase induction motor or engine consists of a single rotating phase in the stator and a rotating cage in the rotor. When phase one supply is connected to the stator winding, a magnetic field is generated. In the pulsating field, the rotor does not rotate due to inertia. So, a single-phase import motor does not start and requires some initial methods.

Question

A 400 V, 3-phase alternator is subjected to an unsymmetrical fault. The
sequence currents are Ia1= -j10 A, Ia2 = j6 A and Iao = j4 A. The sequence
impedances are Z1 = j10 ohm, Z2 = j5 ohm and z0 = j7.5 ohm. Find the
fault current and the type of fault. Also find the terminal voltages (phase and
line) of the generator.

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