(a) Figure Q2(a) shows the percentage differential relay used for the protection of an alternator winding. The relay has minimum pickup current of 0.15 A and a percentage slope of 12%. A high resistance ground fault occurs near the grounded neutral end of the generator winding with the current distribution as shown in Table Q2(a). Identify with reason whether the relay will operate. I CB 400/5 400/5 iz Figure Q2(a) Table Q2(a) Student Name 12 (A) 300 ID (A) 370

(a) Figure Q2(a) shows the percentage differential relay used for the protection of an alternator winding. The relay has minimum pickup current of 0.15 A and a percentage slope of 12%. A high resistance ground fault occurs near the grounded neutral end of the generator winding with the current distribution as shown in Table Q2(a). Identify with reason whether the relay will operate. I CB 400/5 400/5 iz Figure Q2(a) Table Q2(a) Student Name 12 (A) 300 ID (A) 370

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter14: Phase Failure Relays

Section: Chapter Questions

Problem 1SQ: What is the purpose of phase failure relays?

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Similar questions

Which of the following statements is correct? When a fault occurs, Select one: O A. the generator terminal voltage does not change immediately O B. the field current will not change immediately O C. A small regulation error AV forces the AVR to increase the generator field O D. All of the above
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What is the purpose of phase failure relays?
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4. What do you mean by stray load loss of an alternator?
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Q1) Answer the following: - 1-E = (V – laRa ) then N = 2-The consist of and N 3-In a the shunt field winding is connected in parallel with the armature winding only. Series Field Shunt Field R Re 4- The Vo is adjusted by adding This increase slope of this line causing the operating point to shift at lower voltage. No Load V prime mover certain speed. 5-for wave wound generator A= , and for lap wound generator A= 6-The is made up of insulated 7- The connection arrangement to obtain shunt or series excited generators, the field winding is disconnected from the machine and connected across an external supply. is as shown in the figure below. For UC No Supply Load field winding constant speed www