Adaptive Robust Control of Pump-Controlled Hydraulic Erecting System under Overload Conditions

Due to the mechanical structure and layout limitations, the hydraulic pump-controlled erecting system in engineering faces overload conditions during the erecting process. The use of open-loop control, velocity feedforward PID control, or cascade PID control results in poor control accuracy, and it cannot reduce the hydraulic shock during the braking process of the hydraulic system, which can cause system instability. To address this issue, a robust adaptive control strategy based on Lyapunov theory is proposed, taking into account the dynamic characteristics of the effective bulk modulus for hydraulic oil. Simulation results show that the proposed adaptive robust control strategy effectively improves the control accuracy of the whole erecting process. The adaptive robust control strategy effectively suppresses the shock in the system and reduces the vibration amplitude and vibration time of the hydraulic system when the normal condition is changed to the overload condition, thus improving the stability of the system.