EJ2221 Design of Permanent Magnet Synchronous Machines 7.5 credits

Konstruktion av permanentmagnetiserade synkronmaskiner

The aim of the course is to understand how to make an electromagnetic and thermal design of permanent magnet synchronous machines from any given set of specifications. The knowledge is applied by designing a machine for an industrial application.

Offering and execution

Course offering missing for current semester as well as for previous and coming semesters

Course information

Content and learning outcomes

Course contents *

Synchronous electrical machines, permanent magnets, iron lamination, soft magnetic composite, models for losses, thermal modelling, field-weakening, windings, design procedure, finite-element method simulations.

Intended learning outcomes *

After the course, the student should be able to:

  • list different existing topologies of permanent magnet machines
  • describe and compare distributed and concentrated windings
  • explain the principle of field-weakening for permanent magnet synchronous motors
  • choose the appropriate permanent magnet materials for a given construction with regard to functionality, operating conditions, economical and environmental factors
  • explain and compare the properties of iron laminations and soft magnetic composites in relation to their use in electrical machines
  • enumerate different loss components in a machine and relate them to different existing models
  • develop a simple analytical model of the thermal behaviour of a machine taking into account the relevant losses for the application
  • explain all the tasks in the design procedure and apply them to a surface mounted permanent magnet motor with distributed windings with simplified analytical models
  • explain discrepancies between results from different analytical methods through knowledge about the various approximations they are based on
  • describe the concepts of finite element software tools and apply them in the analysis of permanent magnet synchronous machines
  • report and present the results of the design project that has been conducted for a chosen application
  • do a critical evaluation of the report and presentation of the specific studies conducted by the other students

Course Disposition

  • Lectures   12 hours      
  • Tutorials  28 hours       
  • Project   36 hours

The main activity in the course is the project.

Literature and preparations

Specific prerequisites *

Completed Bachelor's degree (180 higher education credits), or equivalent academic qualifications. Documented proficiency in English corresponding to English B/English 6.

Recommended prerequisites

basic course in electrical machines and drives EJ2200 or equivalent course at master level (1st year)




Kurs pärm Design of Permanent Magnet Synchronous Machines, KTH, 2008.

Kurslitteraturen består huvudsaklingen av aktuella forskningsartiklar som utdelas vid kursstart.

Dessutom tillkommer relevant kurslitteratur beroende på vald projektuppgift. Föregående läsårs lista av referenser finns tillgänglig på kursens hemsida.

Examination and completion

Grading scale *

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

Examination *

  • PRO1 - Project Report, 3.0 credits, Grading scale: P, F
  • PRO2 - Assignments, 1.5 credits, Grading scale: P, F
  • TEN1 - Examination, 3.0 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.

Oral examination (TEN1; 3 credits), project reports (PRO1; 3 credits), oral presentations with opposition (PRO2; 1.5 credits)

Other requirements for final grade *

All the different moments have to be passed before the course credits are registered.

Opportunity to complete the requirements via supplementary examination

No information inserted

Opportunity to raise an approved grade via renewed examination

No information inserted


Juliette Soulard

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 EJ2221

Offered by

EECS/Electrical Engineering

Main field of study *

Electrical Engineering

Education cycle *

Second cycle

Add-on studies

EJ210X Master's Project in Electrical Machines and Drives


Juliette Soulard

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.

Supplementary information

Course language: English

Limited number of participants. Priority given to students with passed pre-requesites course with highest grade.

This course is intended for students doing their second year of a master program.