Disturbance Attenuation-Based Global Integral Sliding Mode Control of an Electro-Hydraulic System With Prescribed Performance

Abstract

The uncertainties and external disturbances inevitably reduce the displacement tracking efficiency of an electro-hydraulic system (ELHS). In this paper, the design of observer-based global integral sliding mode control is proposed for an electro-hydraulic system to eliminate the influences of the above-mentioned issues. Firstly, the mathematical model of the ELHS is established in canonical form to compound the impact of lumped disturbances. Then, the enhanced disturbance observer (EDO) is developed to tackle the lumped disturbances with the purpose of ameliorating estimation performance. Furthermore, a global integral sliding-mode surface integrated prescribed performance function is developed, with the goal of boosting global robustness, reducing chattering, and mitigating the significant effects of estimated disturbances error. The evidence of stability is ensured by deploying the Lyapunov principle, and the achievement of finite-time convergence of the ELHS has been attained. By comparing the proposed strategy with other controllers, the comparative experimental studies demonstrate the effectiveness and probability of the suggested method.

Keywords

• Enhanced disturbance observer
• electro-hydraulic system
• prescribed performance
• global integral sliding mode control