|K. H. You, J. H. Lee
|AUTOMATIC CONTROL AND COMPUTER SCIENCES C/C OF AVTOMATIKA I VYCHISLITEL'NAIA TEKHNIKA
The L-norm (or in discrete-time cases the l-norm) is the basis for a controller synthesis procedure that minimizes the peak errors which result from bounded but otherwise unstructured noise (disturbances). In this paper we present details of this theory in explicit form if the system and controller combination is restricted to be third order or less. The design task can be reduced to selection among four (or five) design parameters; namely a finite zero location, a pole location and the natural frequency and damping ratio of a complex pole pair, as well as an overall gain parameter. Design charts as a function of these parameters are given and will be shown sufficient for finding the correct parameters.