(a) You have been asked to assist the designer of a power transmission system. In a symmetric three- phase system, the sum of the instantaneous currents in the three phases is supposed to be zero. The instantaneous currents in each of the three phases are defined as: i(t) = A cos(2π fot + 01) i2(t) = A cos(2 fot + 2) is(t) = A cos(2 fot + 03) The system frequency fo is 60 Hz. The amplitude A varies between 10 and 1000. The designer has chosen o₁ = 0. Your task is to determine values for 2 and 3 such that i₁(t) + 2(t) + i3(t) = 0 or to prove that no values of 2 and 3 will guarantee that the sum of the currents is zero. Choice of 62 and 3: (b) Suppose that the designer decides to change the value of 1 to . Would your answers for 2 and 3 change? Why or why not?

(a) You have been asked to assist the designer of a power transmission system. In a symmetric three- phase system, the sum of the instantaneous currents in the three phases is supposed to be zero. The instantaneous currents in each of the three phases are defined as: i(t) = A cos(2π fot + 01) i2(t) = A cos(2 fot + 2) is(t) = A cos(2 fot + 03) The system frequency fo is 60 Hz. The amplitude A varies between 10 and 1000. The designer has chosen o₁ = 0. Your task is to determine values for 2 and 3 such that i₁(t) + 2(t) + i3(t) = 0 or to prove that no values of 2 and 3 will guarantee that the sum of the currents is zero. Choice of 62 and 3: (b) Suppose that the designer decides to change the value of 1 to . Would your answers for 2 and 3 change? Why or why not?

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

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.14MCQ: The instantaneous power absorbed by the load in a single-phase ac circuit, for a general R LC load...

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