Q1.In the figure below, a percentage differential relay with a slope of 7% and a bias current of 0.1 Alis used to protect the generator coil. When the generator is under load, a short circuit occurs in part of the coil. The currents are shown in the figure. If we assume that the current transformers are 400/5 and without error, does the relay issue a cut-off command in this case? On a diagram, show the characteristic of the relay operation and the points that .represent the operating and blocking currents in the relay -Will changing the conversion ratio of current transformers to 200/5 and 400/1 change the performance of the relay? - If the current 320+j0 is constant, specify what will be the maximum output current of the relay?

Q1.In the figure below, a percentage differential relay with a slope of 7% and a bias current of 0.1 Alis used to protect the generator coil. When the generator is under load, a short circuit occurs in part of the coil. The currents are shown in the figure. If we assume that the current transformers are 400/5 and without error, does the relay issue a cut-off command in this case? On a diagram, show the characteristic of the relay operation and the points that .represent the operating and blocking currents in the relay -Will changing the conversion ratio of current transformers to 200/5 and 400/1 change the performance of the relay? - If the current 320+j0 is constant, specify what will be the maximum output current of the relay?

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...

See similar textbooks

Similar questions

a) Which components determine the excitation current of a transformer? How are they in transformer equivalent circuit modeled? b) Why is the polarity determination of a transformer made? Briefly explain how the experiment is done. c) If the direction of rotation of the motor changes when the feeding ends are changed in a DC motor, what can be said about its type? d) Why does the peak voltage increase as the serial DC generator is loaded? How long does this increase continue?
13. A synchronous machine is run as an unloaded motor. If a low voltage is supplied at the ratedfrequency, and if the full-load armature current flows, a test is being run to determine theA. windage loss.B. I²R loss.C. stray-load loss.D. core loss. Note: I have doubts if it is the letter A or the letter B, can you help me in this question, thanks.
The armature of a 400V, 6-pole, 25 Hz single-phase series motor is lap-wounded with 504 conductors Motor field winding has effective resistance and leakage reactionance are 0.06 22 and 0.05 12, respectively and has 18 turns. However, the armature winding has a leakage reactance of 0.04 12 and negligible resistance. At rated motor current of 300A, the flux per pole is 0.05 Wb, the short circuit current is 50A and the equivalent current to iron losses is 40A. Find motor speed , torque and efficiency at rated current .
electrical machines Explain the load operation test by drawing the test connection diagram of the induction motor.Describe briefly drawing the loaded operating characteristic.
A short shunt compound DC generator delivers a load current of 30 A at 220 V and has armature, series field and shunt field resistances of 0.05, 0.3 and 200Ω respectively. Calculate the induced emf, the armature current and the voltage regulation. Allow 1 V per brush for contact dro
A DC shunt generator has a full load output of 10kW at a terminal voltage of 240V. The armature and the shunt field winding resistances are 0.6 and 160 ohms respectively. The sum of the mechanical and core-losses is 500W. calculate the power required in kW at the driving shaft at full-load, and the corresponding efficiency and voltage regulation
A short shunt compound DC generator supplies a load current of 10A at a voltage of 10 volts. If the resistance of armature, shunt field and series field windings are 0.001 ohm, 1 ohm 0.00 ohm respectively. a) Draw the the figure. And find the generated voltage.
A shunt generator supplies a 31kW load at 230V through cables of resistance, R = 122mΩ. If the field winding resistance, Rf =50Ω and the armature resistance, Ra =51mΩ. Determine the following below: The terminal voltage is, Answer and unit for part 1 The e.m.f. generated in the armature is,
Two identical 3-phase, 500-V induction machines are mechanically coupled for a back-to-back test. One machine is motoring from a 500-V, 50-Hz supply and the other is generating on to a 3-phase, 500-V synchronous machine for which the fre- quency can be controlled. It is required to run the motoring induction mạchine at 40 hp. Neglecting the slight change in the generating machine parameters due to oper- ating at a reduced frequency, estimate the rating of the synchronous machine for this duty and the frequency at which it must be run. Line input readings for each machine No load 500 V 8.5 A 1-6 kW Locked rotor 100 V 30 A 1-6 kW Friction and windage loss per machine 0-8 kW. R = R2'
A gas turbine, 2-pole, 3? synchronous generator rated at 200 MW is connected to the grid (presumed to be an infinite bus). The electrical operating frequency of the grid is 60 Hz, and the slope of the frequency-power curve for the generator is 15 MW/Hz. a. If the no-load setpoint for the generator is set to 63.5 Hz, how much active power will the generator provide to the grid? b. Neglecting system losses, what is the torque provided by the gas turbine? c. What would happen if the no-load setpoint for the generator is set to 59 Hz?
For 3-phase,50 Hz, SCIM, rotor leakage reactance at standstill is twice of it's resistance.The frequency of the supply at which maximum torque is obtained at starting is ?
6. The major failure area of a typical wound-field and wound-armature DC motor isA. brush wear and failure.B. open field windings.C. a faulty commutator segment.