2 research outputs found
A Unified Framework for the H∞ Mixed-Sensitivity Design of Fixed Structure Controllers through Putinar Positivstellensatz
In this paper, we present a novel technique to design fixed structure controllers, for both continuous-time and discrete-time systems, through an H∞ mixed sensitivity approach. We
first define the feasible controller parameter set, which is the set of the controller parameters that guarantee robust stability of the closed-loop system and the achievement of the nominal performance requirements. Then, thanks to Putinar positivstellensatz, we compute a convex relaxation of the original feasible controller parameter set and we formulate the original H∞ controller design problem as the non-emptiness test of a set defined by sum-of-squares polynomials. Two numerical simulations and one experimental example show the effectiveness of the proposed approach
Robust Output Regulation: Optimization-Based Synthesis and Event-Triggered Implementation
We investigate the problem of practical output regulation, i.e., to design a
controller that brings the system output in the vicinity of a desired target
value while keeping the other variables bounded. We consider uncertain systems
that are possibly nonlinear and the uncertainty of their linear parts is
modeled element-wise through a parametric family of matrix boxes. An
optimization-based design procedure is proposed that delivers a continuous-time
control and estimates the maximal regulation error. We also analyze an
event-triggered emulation of this controller, which can be implemented on a
digital platform, along with an explicit estimates of the regulation error