Electric Power Systems 1

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).

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. distinguish between different arc interrupting techniques
  6. argue about utilization of given electric product in specific location in the system
  7. employ softvare tool NEPLAN for power system modeling and short circuit calculations

Forms of Teaching



Independent assignments


Week by Week Schedule

  1. Fundamentals of engineering, standards and IEC standards, Legislation, Permits
  2. Bus bars, Power transformer, Insulators, Isolators, Capacitors, Voltage regulators, Earthing and protection system, Incoming and outgoing lines, Switchyard, Substation design and construction
  3. Principles of operation of transformers, Equivalent circuit and voltage equations, Main and leakage flux; Magnetization current; Inductances, No-load and short-circuit test; Equivalent circuit parameters, Basics of construction of winding and core
  4. Model of line, Model of transformer, Model of feeder, Simple load model
  5. Model of generator, Model of asynchronous motor, Model of power plant
  6. Equivalent circuit diagram for short-circuits, Methods of calculation, Calculation of parameters of short-circuit currents, IEC and other relevant standards, Single phase to ground fault, Double phase fault, Double phase to ground fault, Three phase fault, Three phase to ground fault
  7. Thermal equivalent short-time current, Thermal strength of equipment, Determining optimal cross-section of conductors, Peak short-circuit current, Calculation of stresses in rigid conductors, Forces on supports
  8. Midterm exam
  9. Circuit breakers, Disconnectors, Reclosers, Busbar configurations, Insulation and protection by insulating, Transformers selection and construction, Circuit breakers and disconnectors selection and construction, Earthing and requirements regarding earthing design
  10. Switches, Fuses, Load brake switches, Switching device combinations
  11. Parallel connection, Connection groups, Autotransformer; Intrinsic rated power, Losses; Efficiency; Temperature rise, External characteristics; Voltage drop
  12. Control systems in substations, Monitoring systems in substations, Measuring systems in substations, Communication systems in substations, Protection systems in substations, Reactive power compensation systems, Instrument transformers selection, Auxiliary systems in substations
  13. Project task, Location selection and data collection, Design, layouts and documentation (CAD), Master project, Circuit diagram and connection plans, Consents and approvals
  14. Expert supervision over the equipment development and facility construction, Construction, testing and commissioning, Safety, Environmental impacts, Costs and financial analysis, Timescales
  15. Final exam

Study Programmes

University graduate
Electrical Power Engineering (profile)
Core-elective courses (1. semester)


(.), Visokonaponska rasklopna postrojenja; H. Požar; Tehnička knjiga, Zagreb; 1990; ISBN: 8670591057,
(.), Transparencije s predavanja,
(.), Electric Power Substations Engineering; J.D. McDonald; CRC Press; 2003; ISBN: 0849373832, 9780849373831,
(.), Introduction to Electric Power Systems; (http://ocw.mit.edu/index.html) MIT OpenCourseWare; MIT; 2005; ISBN: -,
(.), Symmetrical Components for Power Systems Engineering; J. Lewis Blackburn; Marcel Dekker; 1993; ISBN: 0849376181, 9780849376184,
(.), Power System Analysis John Grainger, Jr., William Stevenson McGraw-Hill 1994,

For students


ID 223343
  Winter semester
L3 English Level
L2 e-Learning
45 Lectures
15 Exercises
8 Laboratory exercises

Grading System

Very Good