Power System Analysis Problem Sets

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson
Download our mobile app to listen on the go
Get App

Questions and Answers

What is the purpose of the per-unit impedance diagram in Figure 27?

  • To calculate the real power consumed by a load
  • To simplify the analysis of power systems by reducing the number of variables (correct)
  • To visualize the single-line diagram of a power system
  • To determine the nominal voltage of a power system

What is the significance of the '¾»' symbol in the one-line diagram of Figure 28?

  • It represents a step-down transformer
  • It represents a load
  • It represents a step-up transformer (correct)
  • It represents a transmission line

In the per-unit system, what is the advantage of using a base value for voltage and current?

  • It simplifies the analysis of power systems by eliminating the need for complex calculations
  • It allows for the calculation of real power
  • It provides a normalized representation of the power system, enabling easier comparison of different components (correct)
  • It is necessary for the calculation of reactive power

What is the purpose of G1 and G2 in the per-unit impedance diagram of Figure 27?

<p>They represent the generators in the power system (C)</p> Signup and view all the answers

What is the significance of the 'µ´' symbol in the per-unit impedance diagram of Figure 27?

<p>It represents the per-unit value of a component (D)</p> Signup and view all the answers

What is the purpose of the one-line diagram in Figure 28?

<p>To visualize the complexity of a power system (B)</p> Signup and view all the answers

What is the value of S2 in pu?

<p>1.848 + j0.066 (D)</p> Signup and view all the answers

What is the value of V3 in pu?

<p>1.06 0° (B)</p> Signup and view all the answers

What is the value of I3 in pu?

<p>-j0.2 (C)</p> Signup and view all the answers

What is the line-to-line voltage at bus 2?

<p>126.5 kV (C)</p> Signup and view all the answers

What is the value of I2 in pu?

<p>1.68 - j0.06 (C)</p> Signup and view all the answers

What is the line-to-line voltage at bus 1?

<p>27.6 kV (D)</p> Signup and view all the answers

What is the per-unit value of S2 in the given problem?

<p>0.1848 + j0.0066 (D)</p> Signup and view all the answers

What is the value of V3 in per-unit?

<p>1.06 0° (C)</p> Signup and view all the answers

What is the line-to-line voltage at bus 2 in kV?

<p>440 kV (A)</p> Signup and view all the answers

What is the value of I2 in per-unit?

<p>0.054 + j0.332 (A)</p> Signup and view all the answers

What is the transformer reactance in percent?

<p>20% (D)</p> Signup and view all the answers

What is the value of S3 in per-unit?

<p>0 MW + j0.20 (B)</p> Signup and view all the answers

What is the line impedance in ohms?

<p>j66.125 (D)</p> Signup and view all the answers

What is the line-to-line voltage at bus 1 in kV?

<p>480 kV (C)</p> Signup and view all the answers

Flashcards are hidden until you start studying

Study Notes

Problem 3.11

  • The per unit impedance diagram for Problem 3.11 is shown in Figure 27.
  • It consists of two lines: Line 1 with a voltage of 220 kV and Line 2 with a voltage of 110 kV.

Problem 3.14

  • The one-line diagram for Problem 3.14 is shown in Figure 28.
  • The three-phase power and line-line ratings are given as:
    • S2 = 15.93 MW - j33.4 Mvar = 0.1593 - j0.334 pu
    • S3 = 77.00 MW + j14.0 Mvar = 0.7700 + j0.140 pu
  • The line-to-line voltages at buses 2 and 1 are calculated as:
    • V2 = 440 kV
    • V1 = 480 kV

Problem 3.17

  • The one-line diagram for Problem 3.17 is shown in Figure 33.
  • The transformer reactance is 20% on a base of 100-MVA, 23/115-kV.
  • The line impedance is Z = j66.125Ω.
  • The load at bus 2 is S2 = 184.8 MW + j6.6 Mvar and at bus 3 is S3 = 0 MW + j20 Mvar.
  • The voltage at bus 3 is held at 1156 0â—¦ kV.
  • The voltages at buses 2 and 1 are calculated as:
    • V2 = 126.5 kV
    • V1 = 27.6 kV

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

More Like This

Use Quizgecko on...
Browser
Browser