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ECE 581 Electric Power System Protection

3 Credit Hours

Protection systems used to protect the equipment in an electric power system against faults, fault analysis methods, basic switchgear used for protection, basic protection schemes, such as overcurrent, differential, and distance protection and their application. To introduce the current industry practice, the course will have a few guest lecturers from industry.

Prerequisite

Power System Analysis (NC State ECE 451)

Course Outline

This course will cover the basic protection schemes that are used to detect and interrupt the faults in a power system. The course outline is as follows:

  1.  Electric power system protection concepts, goals, philosophies
  2. Per-unit system in power system analysis
  3. Phasors and polarity in three phase systems
  4. Fault current analysis and symmetrical components
  5. Relay input sources
  6. Protection fundamentals and basic design principles
  7. Trip & close circuits, reclosing, and load shedding
  8. Software tools & ETAP
  9. System grounding principles
  10.  Line protection
  11. Transformer protection
  12. Bus protection
  13. Generator protection / Intertie protection for distribution generation
  14. Occasional special topics

Course Requirements

Grade weighting:

Homework & quizzes 25%
Project 25%
Midterm exam25%
Final exam 25%

Textbook and references

Required textbook:

  • Protective Relaying, Principles and Applications, by Blackburn and Domin, 4th edition
    NOTE: this is also a well-recognized reference book for practicing protection engineers

Additional recommended textbooks:

  • Power System Analysis, by Grainger & Stevenson
    NOTE: this is the required textbook for ECE451, and this is also a well-recognized reference book for practicing protection engineers and power system engineers in general.  It has extremely good treatment of symmetrical components, three phase transformers, and other pertinent material.
  • Symmetrical Components for Power Systems Engineering, by J. Lewis Blackburn
    NOTE: this is a well-recognized reference book for practicing protection engineers and power system engineers in general, specifically regarding symmetrical components.
  • Power System Relaying, by Horowitz and Phadke (3rd edition)
    NOTE: Also a good textbook and reference; this was used in ECE581 in the past.

Updated 1/6/2025