2134/11125 Jun Yang Jun Yang Argyrios C. Zolotas Argyrios C. Zolotas Wen-Hua Chen Wen-Hua Chen Konstantinos Michail Konstantinos Michail Shihua Li Shihua Li Robust control of nonlinear MAGLEV suspension system with mismatched uncertainties via DOBC approach Loughborough University 2012 ‘‘Mismatched” disturbances Nonlinear MAGLEV suspension system State-space disturbance observer Disturbance compensation gain Engineering not elsewhere classified 2012-12-07 12:46:51 Journal contribution https://repository.lboro.ac.uk/articles/journal_contribution/Robust_control_of_nonlinear_MAGLEV_suspension_system_with_mismatched_uncertainties_via_DOBC_approach/9225761 Robust control of a class of uncertain systems that have disturbances and uncertainties not satisfying “matching” condition is investigated in this paper via a disturbance observer based control (DOBC) approach. In the context of this paper, “matched” disturbances/uncertainties stand for the disturbances/uncertainties entering the system through the same channels as control inputs. By properly designing a disturbance compensation gain, a novel composite controller is proposed to counteract the “mismatched” lumped disturbances from the output channels. The proposed method significantly extends the applicability of the DOBC methods. Rigorous stability analysis of the closed-loop system with the proposed method is established under mild assumptions. The proposed method is applied to a nonlinear MAGnetic LEViation (MAGLEV) suspension system. Simulation shows that compared to the widely used integral control method, the proposed method provides significantly improved disturbance rejection and robustness against load variation.