Research On Synchronous Control Strategy Of Multiple Hydraulic Cylinder Positions

The hydraulic servo system has the advantages of large driving force,fast response time and high precision.Multi-hydraulic cylinder position synchronization control system has a wide range of applications in heavy industry as well as aerospace and machinery manufacturing.The existence of parameter uncertainties,disturbances,and nonlinearities in the hydraulic system itself constrains the development of hydraulic technology.Multi-cylinder synchronous control systems are coupled with each other,There is still a great difficulty to achieve fast and high precision synchronous control.In response to the problems,this paper designs a multi hydraulic cylinder position synchronization control strategy.The main work of this paper is as follows:(1)For the problem that it is difficult to establish an accurate mathematical model of hydraulic system,a physical model of multi-hydraulic cylinder position synchronization control system is constructed.In this paper,AMEsim software is used to model the single-cylinder hydraulic system and the multi-cylinder synchronous control system.Using a library of hydraulic components in the software for modeling,the model is more accurate and overcomes problems such as ignoring interference and parameter uncertainty in the mathematical modeling process.Build a joint simulation platform between AMEsim and MATLAB through the joint simulation interface in AMEsim.(2)A New Active Disturbance Rejection Control algorithm with improved particle swarm algorithm is proposed for the problem of many parameters of self-tampering controller and the contradiction between performance and jitter.To design New Active Disturbance Rejection Control for the contradiction of performance and jitter of Active Disturbance Rejection Control itself.And for the Active Disturbance Rejection Control parameters are many and coupled,it is difficult to obtain a set of optimal parameters by conventional empirical rectification.The improved particle swarm algorithm is designed to optimize the parameters of the New Active Disturbance Rejection Control,and finally a set of optimal parameters is obtained.Simulation verification was carried out on a single hydraulic cylinder position control system.The simulation results show the effectiveness of the proposed algorithm,which can ensure a good steady-state accuracy and robustness of the control system,and a significant reduction of the jitter amplitude.(3)To address the problems of jitter and finite time convergence of sliding mode control,a time-varying gain improvement sliding mode control based on sigmoid function is designed.By designing the improved convergence rate based on the sigmoid function,the jitter of the control system is greatly reduced,and the exponential term of the designed sliding mode surface in the improved convergence rate speeds up the convergence of the synchronization error.By designing the improved sliding mode surface based on the nonlinear function fal,the jitter problem is improved and the convergence speed is accelerated.By designing the time-varying gain based on fuzzy rules,the gain changes with the control process,which can suppress the disturbance and reduce the jitter well;finally,the design of synchronous control structure is carried out.In this paper,a deviation-coupled synchronous control structure is designed,which contains the states of all subsystems,so the synchronous performance is better.