Given: 275 kW, 3-phase, 6,600 V was tested with the following results. OCT in volts : 5600 : 46.5 With the stator short circuited , a field current of 50 A yields a 6600 7240 8100 SCT in Amps 58 67.5 96 short circuit current of 35 A. Determine by MMF Method the following at unity power factor FIND: 1. FIELD CURRENT REQUIRED TO PRODUCE RATED VOLTAGE AT NO LOAD= AMPS 2. FIELD CURRENT TO NEUTRALIZE THE EFFECTS OF ARMATURE REACTION== AMPS 3. Field current required to produce rated voltage at full load 4. no-load voltage= 5. %VR

Given: 275 kW, 3-phase, 6,600 V was tested with the following results. OCT in volts : 5600 : 46.5 With the stator short circuited , a field current of 50 A yields a 6600 7240 8100 SCT in Amps 58 67.5 96 short circuit current of 35 A. Determine by MMF Method the following at unity power factor FIND: 1. FIELD CURRENT REQUIRED TO PRODUCE RATED VOLTAGE AT NO LOAD= AMPS 2. FIELD CURRENT TO NEUTRALIZE THE EFFECTS OF ARMATURE REACTION== AMPS 3. Field current required to produce rated voltage at full load 4. no-load voltage= 5. %VR

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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Similar questions

If the voltage and current supplied to a circuit orload by a source are˜VS = 170∠(−0.157) V ˜IS = 13∠0.28 Adeterminea. The power supplied by the source which isdissipated as heat or work in the circuit (load).b. The power stored in reactive components in thecircuit (load).c. The power factor angle and power factor.
The circuit shows an unbalanced electrical installation powered by a positive sequence symmetrical three- phase network of 380 V compound voltage. The loads are single phase. Load 1 absorbs an active power of 950 W with f.d.p. 0.5 inductive. Load 2 absorbs an active power of 1,140 W with f.d.p. Unit. Load 3 absorbs from the network an active power of 760 W with f.d.p. 0.5 capacitive. Taking the network voltage URN as the phase reference, calculate: a) complex expressions of the line currents IR. Is. and IT RO- SO- To- : IR Is IT UL-380 V CARGA 1 P₁ = 950 W cos p1=0,5 ind. CARGA 2 P₂=1.140 W cos p₂=1 CARGA 3 P3=760 W cos p3=0,5 cap.
Find the voltage average and the voltage waveform for the output of the circuit shown below.
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The circuit shows an unbalanced electrical installation powered by a positive sequence symmetrical three- phase network of 380 V compound voltage. The loads are single phase. Load 1 absorbs an active power of 950 W with f.d.p. 0.5 inductive. Load 2 absorbs an active power of 1,140 W with f.d.p. Unit. Load 3 absorbs from the network an active power of 760 W with f.d.p. 0.5 capacitive. Taking the network voltage URN as the phase reference, calculate: a) complex expressions of the line currents IR. Is. and IT RO- SO TO IR Is IT U₁-380 V CARGA 1 P₁ =950 W cos p1=0,5 ind. CARGA 2 P₂=1.140 W cos p₂=1 CARGA 3 P3=760 W cos p3=0,5 cap.
2. Three series loads are drawing 20A ms current through a 60HZ source. Load 1 is an 400W, 0.8 lagging induction motor. Load 2 is a 500VA, 0.6 lagging power factor and load 3 is a 2 ohm incandescent bulb. a) What is the total VA of the combined load? b) What is the overall PF of the combined load? c) What RMS voltage is the combined load operating? d) What capacitor VAR must be installed in parallel to the combine load to improve its overall PF to unity? e) What is its approximate capacitance in microfarad?