Electromechanical modelling and active control of flexural rotor vibration in cage rotor electrical machines: Dissertation

Antti Laiho

Research output: ThesisDissertationCollection of Articles

1 Citation (Scopus)


The main objective of this thesis is to develop new tools for model-based control of flexural rotor vibration in cage induction machines. In order to exert the control force on the rotor, a built-in force actuator based on self-bearing principle is considered. A low-order parametric electromechanical model coupling the eccentric-rotor machine, the actuator and rotor-dynamics is developed. Furthermore, numerical analysis of the actuator-rotor system is considered. The numerical analysis is based on time-discretised finite element analysis of the electromagnetic fields in the two-dimensional cross-section of the machine. The finite element analysis is used to estimate the parameters of the low-order model. The numerical analysis provides a tool for both designing the actuator and testing the control algorithms. In the thesis, a control algorithm, previously used mainly in active magnetic bearings for compensation of harmonic disturbance forces, is applied by using the built-in force actuator. In the simulations, the control algorithm is embedded in the numerical analysis. The modelling and model-based control are verified by experiments. A 30 kW two-pole cage induction motor with an extended rotor shaft is used for measurements. The results both from simulations and experiments show that, by using the built-in force actuator, the model-based controller is suitable for flexural rotor vibration suppression in a cage induction machine. In particular, the stable operation at the critical speed of the machine can be achieved by using the methodology presented in this research.
Original languageEnglish
QualificationDoctor Degree
Awarding Institution
  • Aalto University
  • Arkkio, Antero, Supervisor, External person
Award date18 Sept 2009
Place of PublicationEspoo
Print ISBNs978-951-38-7348-6
Electronic ISBNs978-951-38-7349-3
Publication statusPublished - 2009
MoE publication typeG5 Doctoral dissertation (article)


  • induction machine
  • electromagnetic actuator
  • rotor-dynamics
  • self-bearing machine
  • bearingless drive
  • mechanical vibration
  • active control


Dive into the research topics of 'Electromechanical modelling and active control of flexural rotor vibration in cage rotor electrical machines: Dissertation'. Together they form a unique fingerprint.

Cite this