Robust lead-lag compensation for a family of uncertain linear systems

The authors describe a new control design technique for interval systems whose transfer function coefficients are described by some prescribed intervals. The objective of design is to obtain a lead-lag compensator for the given interval system so that the entire family of systems meets given design requirements. The design method is based on new frequency domain tools for such uncertain systems. An algorithm to construct Bode magnitude and phase envelopes for an interval system is presented. Using these frequency domain envelopes, examples for designing robust lead-lag compensators for interval systems are included