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EJ1200 Electric Power Systems 6.0 credits

The course deals with theory, methods, and components for systems where conversion and transmission of electric power are the main objectives. Examples of such systems are speed-controlled drives for electric vehicles and industrial robots, and wind power plants interacting with the utility grid.

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Choose semester and course offering to see information from the correct course syllabus and course offering.

Headings with content from the Course syllabus EJ1200 (Autumn 2021–) are denoted with an asterisk ( )

Content and learning outcomes

Course contents

Basic concepts and problems. Single-phase and three-phase power. Transmission line models. Transmission of power. Ferromagnetic circuits. The transformer. Magnetic forces. The synchronous machine. Single-phase and three-phase power electronic inverters. Electrical drives.

Intended learning outcomes

On completion of the course, the student should:

  • be able to describe the meaning of active, reactive and apparent power.
  • be able to calculate mean values, peak values, rms-values, and harmonics.
  • be able to analyse three-phase systems by means of single phase equivalent circuits, phasor diagrams and the jw-method.
  • be able to describe different types of nodes in an electric power system.
  • be able to make calculations on magnetic circuits.
  • be able to calculate magnetic forces by means of the magnetic force law, virtual work and Maxwell's tensions.
  • be able to describe rotating magnetic fields.
  • be able to describe the function of the transformer, transmission lines, the synchronous machine, one- and three-phase power electronic converters.
  • by using the jw-method, equivalent circuits and phasor diagrams be able to analyse transformers, transmission lines, synchronous machines, and one- and three-phase power electronic converters.
  • be able to calculate power flows in the power system.

Course disposition

No information inserted

Literature and preparations

Specific prerequisites

Completed course corresponding to EI1110 Electrical circuit analysis, extended course.

Active participation in a course offering where the final examination is not yet reported in Ladok is considered equivalent to completion of the course.

Registering for a course is counted as active participation.

The term 'final examination' encompasses both the regular examination and the first re-examination.

Recommended prerequisites

Basic courses of the first two years in the Electrical Engineering programme.
Electromagnetic Field Theory E, 10,5 hp (EI1200), Continuous TimeSignals and Systems, 6 hp EQ1100.


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Examination and completion

If the course is discontinued, students may request to be examined during the following two academic years.

Grading scale

A, B, C, D, E, FX, F


  • LABD - Laboratory work, 0.5 credits, grading scale: P, F
  • LABE - Laboratory work, 0.5 credits, grading scale: P, F
  • LABF - Laboratory work, 0.5 credits, grading scale: P, F
  • TEN2 - Written exam, 4.5 credits, grading scale: A, B, C, D, E, FX, F

Based on recommendation from KTH’s coordinator for disabilities, the examiner will decide how to adapt an examination for students with documented disability.

The examiner may apply another examination format when re-examining individual students.

Opportunity to complete the requirements via supplementary examination

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Opportunity to raise an approved grade via renewed examination

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Profile picture Stefan Östlund

Ethical approach

  • All members of a group are responsible for the group's work.
  • In any assessment, every student shall honestly disclose any help received and sources used.
  • In an oral assessment, every student shall be able to present and answer questions about the entire assignment and solution.

Further information

Course web

Further information about the course can be found on the Course web at the link below. Information on the Course web will later be moved to this site.

Course web EJ1200

Offered by

EECS/Electrical Engineering

Main field of study

Electrical Engineering, Technology

Education cycle

First cycle

Add-on studies

No information inserted


Stefan Östlund

Supplementary information

Replace 2C1240.

In this course, the EECS code of honor applies, see: