G1-2 G2-4G3-2G4-7G5-2G6-1G7-2 Q1 (a)A 3 phase induction motor operating at rated power can be represented by abalanced delta connected load (ZRY etc) of (3G7 + j10) N and is connected toa 3 phase, 4G65 V and 50 Hz supply.Calculate:(i)The three load phase currents (IRY, IYB and IBr).(ii)The three line currents (IR, ly and IB).(iii)The real power (W) in each phase of the load -different methods to calculate this.using 2(iv)The real power (W) supplied by each of the supply phases.The total real power (W) from the supply if the inductionmotor is star connected.(v)(b)A local 3 phase distribution network operating from a 1G6 kV 60 Hz supplyhas a star connected load with nominally balanced load impedances of(1G¬0+j30) Q. In the event of a fault in any of the phases a fourth wire isincluded between the star point of the load and the neutral point of thesupply.Using the information above determine the following for a faulted red phaseload which results in the red phase load resistance and inductance valuesbeing halved (e.g. (150 +j30 becomes 75 +j15):(i)Calculate the 3 lines currents (IR, Iy and IB).(ii)Draw a scaled phasor diagram indicating all phase and linevoltages, and the three line currents.(iii)Using the scaled phasor diagram or otherwise determine thestar-neutral current ISN and suggest the minimum wire diameterto maintain a current density less than 2 A/mm?.(c)Calculate the total 3 phase supply power (W) for the faulted condition in (b)using both the 3 Wattmeter and 2 Wattmeter methods. Comment on theresults.

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Answered: Q1 (a) A 3 phase induction motor…

Q1 (a) A 3 phase induction motor operating at rated power can be represented by a balanced delta connected load (ZRY etc) of (3G7 + j10) 2 and is connected to a 3 phase, 4G65 V and 50 Hz supply.

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...

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