On the Control Effort in Output Feedback Sliding Mode Control of Sampled-Data Systems
For control engineers designing sampled-data sliding mode controllers, this method reduces transient control effort and noise sensitivity.
The paper addresses high control effort in output feedback sliding mode control of sampled-data systems, proposing a disturbance approximation strategy that reduces control effort from O(1/T) to O(1), avoiding deadbeat phenomena and improving noise sensitivity.
In this paper, the problem of output feedback sliding mode control of linear sampled-data multi-input multi-output systems is considered. Existing sliding mode control schemes can attenuate the influence of an external disturbance by driving system states onto a sliding surface. However, they can exhibit high gains during transients, which can be $O(1/T)$ where $T$ is the sampling time period. To address this problem, a new strategy, which employs disturbance approximation, is proposed so that the control effort will be $O(1)$. The new method avoids deadbeat phenomena and hence, it will be less sensitive to noise. Theoretical analysis is provided to show the convergence and robustness of the proposed method. Simulations were conducted to show the efficiency of the proposed approach.