A three phase 6000 V alternator has the following O.C.C. at normal speed: Field current : 14 18 23 30 43 Terminal voltage: 4000 5000 6000 7000 8000 With armature short circuit and fall load current flowing the field current is 17 A And when the machine is suppling fall-load of 2000KVA at zero-power factor the field current is 42.5 A, and the terminal voltage is 6000 V. Determine the field current that required when the machine is supplying the fall-load current at 0.7 p.f. lagging.

A three phase 6000 V alternator has the following O.C.C. at normal speed: Field current : 14 18 23 30 43 Terminal voltage: 4000 5000 6000 7000 8000 With armature short circuit and fall load current flowing the field current is 17 A And when the machine is suppling fall-load of 2000KVA at zero-power factor the field current is 42.5 A, and the terminal voltage is 6000 V. Determine the field current that required when the machine is supplying the fall-load current at 0.7 p.f. lagging.

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter39: Synchronous Motor Operation

Section: Chapter Questions

Problem 14SQ: Induction motors and welding transformers require magnetizing current, which causes a. lagging power...

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