A method to reduce the dynamic order of linear parameter-varying (LPV) systems in grid representation is developed in this paper. It consists of an oblique projection and is novel in its use of a parameter-varying nullspace to define the direction of this projection. Parameter-varying state transformations in general lead to parameter rate dependence in the model. The proposed projection avoids this dependence and maintains a consistent state space basis for the reduced-order system. This extension of the projection framework lends itself very naturally to balanced truncation and related approaches that employ Gramian-based information to quantify the importance of subspaces. The proposed method is first compared to LPV balancing and truncation on a numerical example and then used to approximate two LPV systems: the longitudinal dynamics model of an aeroservoelastic unmanned aerial vehicle and the far wake model of a wind turbine.
Bibliographical noteFunding Information:
Manuscript received October 12, 2016; revised January 30, 2017; accepted February 28, 2017. Date of publication April 28, 2017; date of current version April 11, 2018. Manuscript received in final form March 14, 2017. This work was supported by NASA entitled “Lightweight Adaptive Aeroelastic Wing for Enhanced Performance Across the Flight Envelope,” under Grant NRA NNX14AL36A. Recommended by Associate Editor S. Tarbouriech. (Corresponding author: Julian Theis.) J. Theis and H. Werner are with the Institute of Control Systems, Hamburg University of Technology, 21073 Hamburg, Germany (e-mail: email@example.com; firstname.lastname@example.org).
This work was supported by NASA entitled "Lightweight Adaptive Aeroelastic Wing for Enhanced Performance Across the Flight Envelope," under Grant NRA NNX14AL36A. Recommended by Associate Editor S. Tarbouriech.
© 2017 IEEE.
- Linear parameter-varying (LPV) systems
- model order reduction