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Events at Department of Energy Technology

Industrial/PhD Course: Encoderless control of electric drives motors and generators


14.11.2019 kl. 08.30 - 15.11.2019 kl. 16.00



Professor Frede Blaabjerg - Aalborg University


Professor Ion Boldea, IEEE Fellow, DL, Romania



Variable speed drives are now used for almost 50% of all drives, to control motion(energy flow) to save energy and increase productivity in variable output processes in all industries: from info-gadgets , robotics through transport, pumps, ventilators, compressors etc , home appliances and electric generators for renewable energy conversion and control. Advanced position, speed and torque control that produces high precision and quick response performance requires encoder-precision feedback. In low power(torque) applications ,however, the encoder is more expensive than the motor/actuator and in medium and large power they are mechanically fragile; in all drives the accidental stopping of a drive in a safely critical application means large “production interruption costs” until the faulty encoder is replaced. This is how Encoderless control, with position, speed ,torque and flux state observers came into play; in general applications only encoderless control is used while in servo drives the encoderless control is available at least for redundancy.

The Intensive Course here presents an Overview of present status and trends in Encoderless control of electric drives as follows:


  • V/f and I-f scalar control of ac drives with stabilizing loops for faster torque response, extended speed range and high efficiency with variable load and speed: with sample spectacular results, including regenerative braking experiments
  • Encoderless Field Oriented Control(E-FOC) of IMs ,SPMSMs, IPMSMs, PM-RSMs and dc excited SMs: with case studies
  • Encoderless direct torque and flux control(E-DTFC) of IMs, IPMSMs,PM-RSMs, dc excited SMs: with case studies
  • Encoderless FOC of Induction, Doubly fed induction,doubly fed reluctance(brushless), PM and dc excited synchronous variable speed GENERATORS for wind and hydro ,with case studies
  • Encoderless Direct active and reactive power control(DPQC) of variable speed generator drives, with case studies
  • Robust control of advanced electric drives by case studies: feedback linearization and supertwisting sliding mode FOC and DTFC of IMs and IPMSMs


Basic control theory 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