Electric Traction

Course Description

Electric traction supply systems: 600 V, 1500 V and 3000 V dc, 15 kV alternating at 16 2/3 Hz, and 25 kV and 2x25 kV alternating at 50 Hz. Economic criteria and conditions for railway electrification. Main components of electric traction systems: power sources, electric traction substations, electric traction motors. Types of contact networks: uncompensated, semi-compensated and compensated. Mathematical model of electric traction vehicle movement; driving modes. Traction force. Calculation of electrical conditions in the contact network: voltages, power and energy required for traction. Sizing of stable electric traction substations. Influence of unsymmetrical load of the traction substations on a three-phase high voltage network. Influences of electrified lines on interference and hazard voltages in telecommunication circuits and on signaling and control devices. Electric and magnetic fields under contact lines and near electrical traction facilities. Electric power supply of high-speed railway .

Learning Outcomes

  1. define the basic physical laws and principles required to model the traction system
  2. explain the method of calculation of traction and braking of trains
  3. describe existing traction power systems
  4. describe the main components of the electrical traction system
  5. perform the power supply calculation of stable traction power substations
  6. analyze the environmental impact of stable electric traction substation

Forms of Teaching


Lectures will be held 2 hours a week.


Auditory exercises will be held in 7 cycles lasting 2 hours per week.

Field work

Visit to traction station Zaprešić.

Independent assignments


Grading Method

Continuous Assessment Exam
Type Threshold Percent of Grade Threshold Percent of Grade
Homeworks 0 % 15 % 5 % 0 %
Class participation 0 % 5 % 0 % 0 %
Seminar/Project 0 % 20 % 10 % 0 %
Mid Term Exam: Written 0 % 25 % 0 %
Final Exam: Written 0 % 20 %
Final Exam: Oral 15 %
Exam: Written 50 % 30 %
Exam: Oral 50 %

Week by Week Schedule

  1. DC 600 V, 1500 V and 3000 V, AC 15 kV 16 2/3 Hz, 25 kV and 2x25 kV 50 Hz
  2. Economic and technical criterions and conditions for railway electrification
  3. Main components of electrical traction systems: traction power substations, railway network section switchgear
  4. Construction and types of the contact line systems: non-compensated, semi-compensated and compensated
  5. Determination of the electrical parameters of the railway traction lines
  6. Regime of traction vehicle drives, tractive effort, Calculations of the electrical conditions in the contact line system: voltages, powers and energy demanded for the traction
  7. Calculations of fault currents in the power supply systems for electrical traction
  8. Midterm exam
  9. Power and energy demand, Connections of the stable traction power substations in the three phase power system
  10. Allowed unsymmetry of voltages and currents, Radial and parallel operation of traction substations
  11. Supply of the 2x25 kV system from the 1x25 kV system, Interference- and danger- voltages in telecommunication, signal and control circuits and equipment
  12. Electric and magnetic fields under contact lines and in proximity of the traction power installations
  13. Influences of eddy currents on underground metallic pipes and cables
  14. Power supply of high speed rail, Electromagnetic levitation
  15. Final exam

Study Programmes

University graduate
Audio Technologies and Electroacoustics (profile)
Free Elective Courses (1. semester)
Communication and Space Technologies (profile)
Free Elective Courses (1. semester)
Computational Modelling in Engineering (profile)
Free Elective Courses (1. semester)
Computer Engineering (profile)
Free Elective Courses (1. semester)
Computer Science (profile)
Free Elective Courses (1. semester)
Control Systems and Robotics (profile)
Free Elective Courses (1. semester)
Data Science (profile)
Free Elective Courses (1. semester)
Electric Machines, Drives and Automation (profile)
Free Elective Courses (1. semester)
Electronic and Computer Engineering (profile)
Free Elective Courses (1. semester)
Electronics (profile)
Free Elective Courses (1. semester)
Information and Communication Engineering (profile)
Free Elective Courses (1. semester)
Network Science (profile)
Free Elective Courses (1. semester)
Software Engineering and Information Systems (profile)
Free Elective Courses (1. semester)


Friedrich Kiessling, Rainer Puschmann, Axel Schmieder, Egid Schneider (2018.), Contact Lines for Electric Railways: Planning, Design, Implementation, Maintenance, Wiley
I. Švaljek, T. Kožulj, M. Bošnjak (2003.), Tehničko-eksploatacijski pokazatelji i značajke vučnih vozila Hrvatskih željeznica,, Željeznička tiskara d.o.o
V. Profillidis (2016.), Railway Management and Engineering, Routledge
Zavada, Josip (2004.), Željeznička vozila i vuča vlakova, Fakultet prometnih znanosti
Krzysztof Karwowski, Adam Szeląg (2009.), Modern electric traction, Gdansk University of Technology

For students


ID 222575
  Winter semester
L3 English Level
L1 e-Learning
30 Lectures
15 Exercises

Grading System

90 Excellent
75 Very Good
65 Good
55 Acceptable