Induced L2 norm improvement by interpolating controllers for discrete time LPV systems

Artikel i vetenskaplig tidskrift, 2009

The paper shows an interpolation-based control solution asapossible technique to formulate the constrained H∞ control problem for discrete-time linear parameter varying (LPV) systems. The control policy is constructed by interpolating amongapriori designed, unconstrained, constant, state feedback controllers. Invariant set theory is used to introduce the measure of the domain of applicability. It is shown that the `trade-off' between the performance and the size of the domain of applicability can be significantly reduced by controller interpolation. Hence, the interpolation-based controller becomes applicable overamuch larger region than any other single state feedback. The proposed method gives stabilizing solution not only under hard constraints, but also allows the online modification of the induced L² norm from the generalized disturbance input to the predefined performance output. Moreover, the suggested method can be applied in real-time environment.