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Industrial/PhD Course: Reluctance electric motor drives for high efficiency in line start and variable speed applications


11.11.2019 kl. 08.30 - 13.11.2019 kl. 16.00



Professor Frede Blaabjerg - Aalborg University


Professor Ion Boldea, IEEE Fellow, DL, Romania

ECTS: 2,5


The need for higher efficiency motors at reasonable initial costs for line start and for variable speed applications is growing by the day. The high cost of high energy PMs has prompted vigorous R&D in Academia and Industry worldwide in “Reluctance electric machines which use less high energy PMs (per Nm), or low cost Ferrite- PMs for still higher efficiency than in IMs, for competitive torque/volume and at reasonable costs”. Recently, reluctance Synchronous Motor (RSM) variable speed drive reached wide markets from 10 to 500 (even 1500) Kw power in 4 pole multiple flux barrier cageless rotors, with distributed stator windings; the same is true for line start 3 and 1 phase cagerotor reluctance PM line start small motors in home appliances. The present Course presents the Status and Trends in Reluctance electric machine drives (REMDs), for line start and variable speed as follows:

Principles, classifications, merits and demerits of:

  • Reluctance synchronous motor drives with cageless an cage rotors without and with PMs
  • Flux- modulation REMDS: Flux –modulation principle and its application to Switching -Flux, Vernier, Flux-Reversal, Transverse-Flux, Dual- Rotor Flux- Modulation motor/generator drives (with magnetic gear effects)
  • 3- and 1-phase line start Reluctance Synchronous motors without and with PMs for high efficiency, mainly in small power applications; modeling and design with sample simulation and test results
  • 3-Phase Reluctance synchronous motor variable speed drives : modeling, optimal design and control: with case studies
  • Ferrite- PM- claw- pole- rotor Synchronous Motor drives design and control with sample results of high torque density and high efficiency
  • BLDC-MRM (multiphase reluctance motor) drives design and control with case study and experimental results of 4/1 CPSR
  • Brushless Doubly Fed Reluctance machine (B-DFRM) drive: design and control for wind energy
  • Switching- Flux (double saliency) machine drives with PMs and (or) dc stator excitation for wide CPSR; modeling and control with illustrative implementation examples
  • Vernier PM machine drives with higher power factor and high torque density and reasonable efficiency and cost in low speed high torque applications: with case study
  • Transverse –Flux machine drives with stator or rotor PMs and without PMs for high torque density, high efficiency at moderate power factor and initial costs in low speed applications
  • Flux Reversal machine drives with double saliency, stator or rotor PMs and 6(12) stator non-overlapping multi-polespan ac coils for 3 phase implementation ;with sample results
  • Dual Rotor Flux-Modulation machine drives with rotor and or stator PMs and magnetic gear (torque magnification) effects for very low speed high torque direct (pseudo-direct) drives; with sample representative results


Basic theory about machine drives and MATLAB/Simulink

Form of evaluation

Quiz in class (90%) and attendance rate (10%)




6000 DKK for PhD students outside of Denmark and 8000 DKK for the Industry.


Department of Energy Technology


Aalborg University, Pontoppidanstræde 103, room 4.112, 9220 Aalborg East