چكيده به لاتين
Usually, the stability problem of linear parameter varying systems with piecewise-constant parameters is evaluated through an independent quadratic lyapunov function due to sudden changes and discontinuous characteristics of the parameter trajectory. But, by doing so, we would fail in capturing the fact that, in between jumps, the parameters are constant. Corentin Briat introduced a stability analysis approach based on the procedure of analyzing hybrid and switching systems, due to the similarity of them to piecewise-constant LPV models, regarding the concept of dwell time.
In this thesis, as an extension to Briat's work, we present the sufficient conditions for designing a clock-dependent state feedback controller to ensure the stability and improve disturbance attenuation (L2-gain) level of piecewise-constant LPV systems. After that, due to the induced constraints on control signal in most of the practical systems, the design conditions of a controller with respect to state constraints and input saturation will be presented, following by an applicable example of a DC_DC buck converter, to show the effectiveness of this approach.
To derive the design conditions, the best way is to use linear matrix inequality techniques. For this purpose, a new approach and a related roolbox is introduced to convexify the parameter dependent LMIs based on transforming the parametric space to multi-simplex domain.
Keywords: piecewise-constant LPV systems, switching systems stability, disturbance attenuation, multi-simplex space, DC voltage converters.
