Study on the modified nonlinear integral sliding mode control for the valve-controlled cylinder electro-hydraulic position servo system

To enhance the position tracking accuracy of valve-controlled cylinder electro-hydraulic position servo systems, an improved nonlinear integral sliding mode control method is proposed. Firstly, a nonlinear mathematical model of the electro-hydraulic position servo system is established. Subsequently, a nonlinear integral sliding mode controller is designed, where a nonlinear integral error function is introduced on the sliding surface and the reaching law is modified to suppress chattering. The controller stability is rigorously validated using Lyapunov stability theory. Finally, a simulation model of the electro-hydraulic servo position control system is constructed using Simulink software. The designed controller is verified through simulations, and its control performance under different input signals is comprehensively analyzed. The results demonstrate that the proposed nonlinear integral sliding mode control algorithm effectively enhances the position tracking accuracy, transient performance, and disturbance rejection capability of the electro-hydraulic position system, exhibiting superior robustness and improved control effectiveness.