| With the continuous development of industrial intelligence and the demand for highstrength loads of large-scale equipment,the application of multi-electro-hydraulic servo actuator system in various fields has become more and more extensive.This paper introduces the research and development status of electro-hydraulic servo system and multi-agent system.It models and analyzes a type of multi-electro-hydraulic servo actuator system.It uses multi-agent theory and nonlinear control theory as tools,and focuses on multi-agent systems distributed tracking synchronization control problem of electro-hydraulic servo actuator system under directional communication topology.The work of this paper is mainly divided into the following aspects:Analyze and introduce the composition and working principle of the multi-electrohydraulic servo actuator system.Use hydraulic transmission theory to establish nonlinear dynamics model,use graph theory to establish communication topology model,and obtain the state space model of N nodes system.In case of the absence of external load disturbance in the system,the distributed synchronization tracking problem of multi-electro-hydraulic servo actuator system is studied.According to the communication relationship between adjacent nodes,the synchronization error and the state error are designed,and the distributed synchronization control law is designed using the nonlinear back-stepping method.The Lyapunov stability theory is used to prove that the controller makes the system asymptotically stable,and the synchronization error and tracking error tend to zero.In case of the external load disturbance and parameter uncertainty of the system,the distributed synchronization tracking problem of the multi-electro-hydraulic servo actuator system is studied.An improved high-gain disturbance observer is designed to observe the total disturbance and avoid the large noise caused by the state variable differentiation.The disturbance observation compensation is added to the distributed synchronous control law to realize the compensation for disturbance and parameter uncertainty.Combining the stability theory and the uniformly ultimately bounded theory,it is proved that the system synchronization error and disturbance observer error are uniformly ultimately bounded and the tracking error is UUB when there is a directed spanning tree with the leader as the root node in the communication topology.Finally,the simulation in Simulink verifies that the distributed synchronization tracking algorithm with disturbance compensation makes the system have better tracking performance.Aiming at the input saturation characteristics of the servo valve,a method to reduce the saturation time of the control law of the multi-electro-hydraulic servo actuator system is studied.By designing the auxiliary system,it is combined with the synchronous control law designed by the nonlinear back-stepping to improve the anti-saturation performance of the system.Combining stability theory and UUB theory,it is proved that the system synchronization error,and auxiliary system variables are ultimately uniform bounded.Finally,the simulation in Simulink verifies the effectiveness of the designed algorithm.Build an experimental platform composed of three electro-hydraulic servo actuators,and introduce the composition and implementation principles of the platform.The three tracking synchronization control algorithms designed in this paper are experimentally verified on this platform.The effectiveness of the proposed algorithm is verified through comparative experiments,and the tracking accuracy of 0.5hz sine trajectory reaches 2.5%-5%. |
