Electric Facilities

Course Description

Introduction to electric power systems.Voltage and current stresses in switchgear and industrial systems.Symmetrical and unsymmetrical three-phase systems.Symmetrical components. Sequence impedances. Short circuit currents in three-phase AC systems.International Standards and specifications for calculation of short circuit currents.Short circuit current components (peak short circuit current, breaking current, thermal and dynamic short circuit strength).Substations and switchgear systems design.Selection criteria and planning guidelines for switchgear and distribution systems.Electric power transformers.Measuring (current and voltage) transformers.Main circuit assemblies.Electric facilities and distribution networks protection.Measuring. Overvoltage protection.Reactive power compensation.Grounding systems.Protection against electric shock (direct and indirect contact).

General Competencies

Having successfully completed the module, students will be able to demonstrate knowledge and understanding of fault analysis, fundamental concepts of substations and switchgear systems design, reactive power compensation, concept of protection against overvoltages and electric shock, brief introduction to how computer methods and relevant standards are applied.

Learning Outcomes

  1. define basic parts of electric facilities and their purposes
  2. identify basic parts of electric facilities on field
  3. describe current-voltage conditions in balanced and unbalaced systems
  4. solve short circuit problem on simple power system example
  5. employ softvare solutions for power system modeling and short circuit calculations
  6. distinguish between different arc interrupting techniques
  7. choose adeqate electric products for specific location in the system
  8. argue about utilization of given electric product in specific location in the system

Forms of Teaching


Lectures are performed every week except in weeks when exams take place. Weekly lecture load is 3 hours. Use of electronic student response system.


There are two examinations during the lectures.


Calculations are integral part of the lecture

Laboratory Work

NEPLAN is using for modeling and calculation of short circuits


Lecturers are available for consultations any time upon agreement, via e-mail or in person.

Structural Exercises

NEPLAN is using for modeling and calculation of short circuits

Grading Method

Continuous Assessment Exam
Type Threshold Percent of Grade Threshold Percent of Grade
Quizzes 33 % 10 % 33 % 10 %
Seminar/Project 33 % 15 % 33 % 15 %
Mid Term Exam: Written 33 % 25 % 0 %
Final Exam: Written 33 % 35 %
Final Exam: Oral 15 %
Exam: Written 50 % 50 %
Exam: Oral 25 %

Week by Week Schedule

  1. Introduction. New directions in power systems.
  2. Power system basics.
  3. Three phase systems (phasors, current, voltage, symmetrical components)
  4. Modeling of power system components 1
  5. Modeling of power system components 1
  6. Short circuit calculation
  7. Main parts of facilities (buses, insulators, disconectors, circuit-breakers)
  8. Exams
  9. Exams
  10. Low voltage switch devices
  11. Power and measurement transformers, secondary systems
  12. Connection diagrams for main circuits
  13. Power system protection
  14. Final chapters (measurements, reactive power compensation, earthing, insulation)
  15. Preparations for exams

Study Programmes

University undergraduate
Electrical Power Engineering (module)
(5. semester)


S. Krajcar; M. Delimar (2011.), Transparencije s predavanja (www.fer.hr/zvne), FER
H. Požar (1990.), Visokonaponska rasklopna postrojenja, Tehnička knjiga, Zagreb
J.D. McDonald (2003.), Electric Power Substations Engineering, CRC Press
(http://ocw.mit.edu/index.html) MIT OpenCourseWare (2005.), Introduction to Electric Power Systems, MIT
J. Lewis Blackburn (1993.), Symmetrical Components for Power Systems Engineering, Marcel Dekker
(.), Power System Analysis John Grainger, Jr., William Stevenson McGraw-Hill 1994,

Associate Lecturers


Laboratory exercises