Research On The Reliability Of FAST Hydraulic Actuator Group System

The FAST hydraulic actuator group system is a typical local large-scale electromechanical-hydraulic integration system.As the most important moving component group in the active reflective surface system of the FAST radio telescope,its reliable operation is an important basis for normal observation of the radio telescope.Vibration,hydraulic oil pollution,aging of components and harsh external working environment in the system will accelerate the occurrence of system failures and component failures in the hydraulic actuator group,affecting the normal observation work of the FAST radio telescope.This article takes the hydraulic actuator group system as the research object,and relies on the FAST large-scale radio telescope project that has been put into use to carry out research work on reliability-related issues.First,the reliability acceleration degradation test is carried out for a single hydraulic actuator test prototype.By analyzing the failure problems and phenomena that occur in the actuator prototype during the test,the failure form and type of the basic unit of the hydraulic actuator group system Preliminary understanding,preliminary analysis shows that hydraulic actuators are prone to failures,including bidirectional gear pumps,hydraulic oil pollution,and system pipelines.After analyzing the factors of prototype failures in the system,corresponding solutions are proposed,and The fluid simulation software was used to verify the solution,which finally solved the failure problem of the hydraulic system of the sample prototype and laid the foundation for analyzing the reliability of the group system.Then based on the relevant data of hydraulic oil pressure,hydraulic oil temperature and position accuracy error of hydraulic cylinder and cylinder rod monitoring during radio telescope operation,using T-S fuzzy fault tree theory knowledge,a hydraulic actuator group was established.The fuzzy fault tree of the system proposes the fault search decision of the group system through the algorithm and the solution process of importance,which reduces the complexity of the daily maintenance process and fault resolution mechanism of the radio telescope,and provides support for the normal operation and post-maintenance of the FAST project,Enrich and improve the engineering system of the reliability analysis of complex engineering systems such as actuator groups,and provide theoretical and technical support for the design and construction of other similar projects.