A 4-pole, 250V, 120kW, DC short shunt compound generator has the following parameters: Ra=0.015 Ω, Rse=0.01 Ω, Rf =125 Ω, flux per pole=3x10 ଺ maxwells, Speed=1000rpm, hysteresis loss=2.5kW, eddy current loss=1.5kW, total mechanical loss=5kW. At what speed and excitation does this generator needs to operate in order to maintain an overall efficiency of 88%. Note: Excitation needs to be adjusted with speed in order to generate the same emf

A 4-pole, 250V, 120kW, DC short shunt compound generator has the following parameters: Ra=0.015 Ω, Rse=0.01 Ω, Rf =125 Ω, flux per pole=3x10 ଺ maxwells, Speed=1000rpm, hysteresis loss=2.5kW, eddy current loss=1.5kW, total mechanical loss=5kW. At what speed and excitation does this generator needs to operate in order to maintain an overall efficiency of 88%. Note: Excitation needs to be adjusted with speed in order to generate the same emf

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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