Backstep control of electro-hydraulic servo double-cylinder synchronous lifting system
Aiming at the problems of complex control and strong nonlinearity of the electro-hydraulic servo dual-cylinder synchronization system,a backstepping control algorithm was proposed.The semi-physical simulation technology was used to complete the synchronization accuracy of the electro-hydraulic servo synchronization system and the simulation verification of the backstepping controller.Firstly,the mathematical model of electro-hydraulic servo dual-cylinder synchronous system was studied.The nonlinear state space equation of electro-hydraulic servo synchronous system was derived according to the basic equation of valve-controlled cylinder and the dynamic equation of beam.Through coordinate transformation,the equation was sorted into matrix form and sorted into strict feedback form,which met the application conditions of backstepping control law.Then,according to the Lyapunov stability theory and the backstepping control principle,the backstepping control law was derived for the electro-hydraulic servo dual-cylinder synchronous system,and the backstepping controller was programmed by C language.Finally,the experimental verification of the backstepping control strategy of the electro-hydraulic servo dual-cylinder synchronous system was completed on the semi-physical simulation platform composed of industrial computer and advantech USB-4704 data acquisition card.The experimental results show that comparing with the conventional PID control,the error between the actual displacement and the expected displacement of the hydraulic cylinder is smaller.The displacement tracking error of the single hydraulic cylinder is reduced from 6.5 mm to 2.3 mm,which is reduced by 64.6%.The maximum synchronization error of the two-cylinder synchronous system is reduced from0.25 mm to 0.21 mm,which is reduced by 16%.The designed backstepping controller significantly improves the control accuracy and system stability of the two-cylinder synchronous control system.
valve-controlled cylinderbackstepping control algorithmbackstepping controllernonlinear state space equationdynamic equation of beamhardware-in-the-loop simulation