Performance Analysis Of Ultra-high-flow Hydraulic Control System And Multi-machine Shared Hydraulic Source

The compression shear tester is mainly used for various bridge plate type,basin type and other rubber bearings to perform mechanical performance tests on the axial radial compression,shear resistance and rotation angle of the rubber bearings under the composite conditions of compression and shear resistance.It is used to detect performance parameters such as compressive elastic modulus,shear elastic modulusand allowable shear angle of the support,etc.With the development of bridge construction,heavy and long-span bridges are increasing day by day,the bearing tonnage requirements for bearings are becoming higher and higher,and the corresponding tonnage requirements for compression shear tester are also becoming higher and higher.In order to meet the requirements for testing the mechanical properties of the rubber bearing of the super-large tonnage bridge,the super-large tonnage static and dynamic multi-directional loading equipment was specially developed.At the same time,in order to reduce the installed power and save space costs,multiple equipments share an oil source system.The hydraulic control and oil source system are the core components of the mechanical test of the whole equipment to achieve compression,shear,allowable shear angle,rotation angle and so on.Its performance is directly related to the performance of the entire equipment.The subject focuses on the research of the hydraulic control system and multi-machine shared hydraulic source.First of all,the domestic and foreign research literatures are sorted out and analyzed.According to the technical requirements,the equipment loading principle,the vertical loading and horizontal shear loading conditions,the system performance of the oil supply mode and the speed regulation mode are analyzed.The analysis lays the foundation for the theoretical calculation and simulation of the subsequent system.Secondly,according to the characteristics of the working conditions of shearing instantaneous large flow rate and multiple devices working at the same time,a common hydraulic source for multiple machines with"accumulator group+hydraulic pumps"combined oil supply is proposed,the static and dynamic loading hydraulic source distribution strategy is analyzed.The pressure reducing valve stabilizes the outlet pressure of the auxiliary power source accumulator group,and the pipeline accumulator absorbs the pressure fluctuation under the disturbance of large flow.AMESim modeling and simulation results show that the multi-machine shared hydraulic source meets the system performance requirements,the pump source and auxiliary power source branch merge normally,the pipeline accumulator can absorb pressure fluctuations well and pressure fluctuation ranges under the circuit large flow disturbance from-8.46%～2.25%to-1.46%～1.04%,and keep the output pressure relatively stable.Then,based on the schematic diagram of the horizontal shear subsystem,a loop mathematical model is established,the transfer function is derived,and the dynamic characteristics are modeled and simulated.The control variable method is used to study the layout strategy of the proportional valve,the diameter and length of the main pipeline,the elastic modulus of proportional valve outlet hose,oil elastic modulus on control performance and gives the necessity of system optimization and correction.Adaptive fuzzy PID control is introduced into system,AMESim-Simulink co-simulation fuzzy controller is designed,and the dynamic characteristics of the system are compared under conventional PID and adaptive fuzzy PID control.The results show that under adaptive fuzzy PID control,the system has better dynamic characteristics.Under the actual sinusoidal conditions,the steady-state deviation of the system displacement drops to-1.32%～1.63%and good x_p-F loading characteristics.Finally,the principle of 60MN equipment synchronization is analyzed,and the mathematical model of vertical loading synchronization circuit is established according to the"master-slave mode"hydraulic synchronization system schematic diagram,and the transfer function is derived.The modeling simulation shows that the system is stable,the maximum synchronization error is 0.69mm,the pressure fluctuation during holding pressure is-0.13%～0.18%and good x_p-F loading characteristics.