[Q1]/A/A 2300-V, three phase, 60 Hz, star-connected cylindrical synchronous motor has a synchronous reactance of 11 Q2 per phase. When it delivers 200 hp, the efficiency is found to be 90% exclusive of field loss, and the power-angle is 15 electrical degrees as measured by a stroboscope. Neglect ohmic resistance and determine: (a) the induced excitation per phase. (b) the line current la (c) the power factorB/ explain the effects of excitation voltage or current on synchronous motor and generator performances.

[Q1]/A/A 2300-V, three phase, 60 Hz, star-connected cylindrical synchronous motor has a synchronous reactance of 11 Q2 per phase. When it delivers 200 hp, the efficiency is found to be 90% exclusive of field loss, and the power-angle is 15 electrical degrees as measured by a stroboscope. Neglect ohmic resistance and determine: (a) the induced excitation per phase. (b) the line current la (c) the power factorB/ explain the effects of excitation voltage or current on synchronous motor and generator performances.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter12: Power System Controls

Section: Chapter Questions

Problem 12.4P

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