Title :
Robust steady-state tracking
Author :
Khammash, Mustafa H.
Author_Institution :
Dept. of Electr. Eng. & Comput. Eng., Iowa State Univ., Ames, IA, USA
fDate :
29 June-1 July 1994
Abstract :
This paper addresses the robust performance problem when the performance measure is the "steady-state" value of an error signal. Necessary and sufficient conditions are derived for robust steady-state tracking of fixed inputs in the presence of structured time-varying uncertainty are derived. These conditions are easily computable and fit well with existing conditions on stability robustness and performance robustness when the performance measure is the level of disturbance rejection. Using these conditions, it is shown that time-varying perturbations of a nominal LTI plant can result in large steady-state tracking errors to fixed inputs even if the nominal plant and controller give zero steady-state tracking errors.
Keywords :
robust control; stability criteria; time-varying systems; uncertain systems; disturbance rejection; error signal; necessary and sufficient conditions; nominal LTI plant; performance measure; performance robustness; robust steady-state tracking; stability robustness; steady-state tracking errors; steady-state value; structured time-varying uncertainty; time-varying perturbations; Error correction; Measurement uncertainty; Robust control; Robust stability; Robustness; Steady-state; Sufficient conditions; Transfer functions;
Conference_Titel :
American Control Conference, 1994
Print_ISBN :
0-7803-1783-1
DOI :
10.1109/ACC.1994.751851