| 摘要: |
| The paper shows that a control strategy with disturbance rejection is able to reduce the control effort to a minimum, ensuring at the same time a desired performance level. The disturbance to be rejected is completely unknown, except for a sectorial bound. The control unit is endowed with an extended state observer which includes a disturbance dynamics, whose state tracks
the unknown disturbance to be rejected. In summary, the novel contributions of the paper are the following. First, we derive a robust stability condition for the proposed control scheme, holding for all the nonlinearities that are bounded by a known (or estimated) maximum slope. Second, we propose a novel approach for designing the observer and state feedback gains, which
guarantee robust closed-loop stability. Third, we show that the designed control system yields, with a minimum control effort, the same control performance as a robust state feedback control, which on the contrary may require a larger command activity.
Two simulated case studies are presented to show the effectiveness of the proposed approach. |
| 关键词: Disturbance rejection, extended observer, robust stability, sector-bounded nonlinear systems |
| DOI： |
| Received:January 25, 2016Revised:April 18, 2016 |
| 基金项目: |
|
| Control of systems with sector-bounded nonlinearities: robust stability and command effort minimization by disturbance rejection |
| C. Novara,E. Canuto,D. Carlucci |
| (Politecnico di Torino) |
| Abstract: |
| The paper shows that a control strategy with disturbance rejection is able to reduce the control effort to a minimum, ensuring at the same time a desired performance level. The disturbance to be rejected is completely unknown, except for a sectorial bound. The control unit is endowed with an extended state observer which includes a disturbance dynamics, whose state tracks
the unknown disturbance to be rejected. In summary, the novel contributions of the paper are the following. First, we derive a robust stability condition for the proposed control scheme, holding for all the nonlinearities that are bounded by a known (or estimated) maximum slope. Second, we propose a novel approach for designing the observer and state feedback gains, which
guarantee robust closed-loop stability. Third, we show that the designed control system yields, with a minimum control effort, the same control performance as a robust state feedback control, which on the contrary may require a larger command activity.
Two simulated case studies are presented to show the effectiveness of the proposed approach. |
| Key words: Disturbance rejection, extended observer, robust stability, sector-bounded nonlinear systems |
