Closed Loop System Identification of a Torsion System
Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesisAlternative title
Systemidentifiering av ett återkopplat torsionssystem (Swedish)
A model is developed for the Quanser torsion system available at Control Systems Research Laboratory at Chulalongkorn University. The torsion system is a laboratory equipment that is designed for the study of position control. It consists of a DC motor that drives three inertial loads that are coupled in series with the motor, and where all components are coupled to each other through torsional springs.
Several nonlinearities are observed and the most significant one is an offset in the input signal, which is compensated for. Experiments are carried out under feedback as the system is marginally stable. Different input signals are tested and used for system identification. Linear black-box state-space models are then identified using PEM, N4SID and a subspace method made for closed-loop identification, where the last two are the most successful ones. PEM is used in a second step and successfully enhances the parameter estimates from the other algorithms.
Place, publisher, year, edition, pages
2009. , 60 p.
nonlinear compensation, subspace, PEM
IdentifiersURN: urn:nbn:se:liu:diva-17531ISRN: LiTH-ISY-EX- - 09/4223 - - SEOAI: oai:DiVA.org:liu-17531DiVA: diva2:210479
2009-03-06, Glashuset, Linköpings Universitet, Linköping, 10:15 (Swedish)
Banjerdpongchai, David, Associate Professor
Eriksson, Lars, Associate Professor