|Control of Large Model Mismatch Systems using Multiple Models
Feng Gao*, Dongfang Dang, Shengbo Eben Li, and MengChu Zhou
International Journal of Control, Automation, and Systems, vol. 15, no. 4, pp.1494-1506, 2017
Abstract : "H∞ control is an effective approach to handle model uncertainties. However, when modeling mismatch
is large, it tends to be challenging to meet the desired requirements of both stability and performance by only using
a single H∞ controller. This study presents a switching method to enhance the robust stability and performance
of H∞ control by dividing the range of dynamics into multiple uncertain models. The candidate robust controllers
are designed by solving a set of linear matrix inequalities for each uncertain model. A structural scheduling logic
that selects the most proper controller into closed-loop is proposed. The selected controller can ensure bounded
exponentially weighted H∞ norm of the closed-loop switching systems. This work analyses their robust stability
and disturbance attenuation performance via a linear fractional transformation by using the small gain theorem. The
effectiveness of this method is validated with a fist-order inertial system with pure time delay."
H∞ performance, large uncertainty, multiple models, robust control.