Research On Hydraulic System Of Fast Electro-hydraulic Actuator

FAST is the abbreviation of Five-hundred-meter Aperture Spherical radio Telescope.The research object of the paper is the electro-hydraulic actuator applied to the FAST.The electro-hydraulic actuator is the power unit of the active reflector system of the radio telescope,and functions to control the surface shape of the radio telescope.In order to make the electro-hydraulic actuator work better,the hydraulic system of this type of electrohydraulic actuation is analyzed.Based on the overall understanding of the electro-hydraulic actuator,the working principle and application environment of this type of electro-hydraulic actuator are combined with the expertise of fluid mechanics to analyze the hydraulic system of the electro-hydraulic actuator.And The way is proposed to increase the flow channel of the hydraulic system.In order to analyze reasonably and efficiently,this paper uses a variety of tools for auxiliary research.The AMESim simulation software was used to model and analyze the hydraulic system of the electro-hydraulic actuator.According to the actual working conditions of the electro-hydraulic actuator,the basic parameters of the appropriate components,the model pipeline parameters and the transmission medium parameters are selected.Only changing the diameter of the pipe,The pressure changes of the critical parts of the hydraulic system under different operating conditions before and after optimization are calculated.The two-dimensional analysis model of the gear pump in the hydraulic system is established.The model is analyzed the internal flow field under different inlet pressure conditions with the dynamic mesh and multi-phase flow simulation model of the FLUENT simulation module in ANSYS.In the case,at the same simulation time point,the gas phase distribution in the gear pump are studied.The FAST electro-hydraulic actuator loading test bedstand is built.The bedstand can simulate the actual stress conditions of the electro-hydraulic actuator.Under the same test conditions,the electro-hydraulic actuators before and after optimization are tested and studied.The performance of the electro-hydraulic actuator before and after optimization are analyzed from different aspects.At the last,the correctness of the optimization method is obtained.