| Multi-way valve is the core control component of the hydraulic system of construction machinery,which determines the performance of host operation to a large extent,such as accuracy,comfort,reliability and energy efficiency.Because of the late start of the hydraulic technology in China,the technical level of multi-way valve is low.Compared with mature foreign multi-way valve,the basic performance including micro-motion characteristics of domestic products is poor,which result in it difficult to meet users’ requirements.Therefore,it’s necessary to study multi-way valve for domestic technicians.This paper took a series of load-sensing multi-way valves as the research object,the quantitative analysis was carried out according to the existing problems on micro-motion characteristics,and the simulation analysis and experimental research are carried out.This paper complete the following aspects:Firstly,after understanding the working principle of the load-sensitive multi-way valve and the function of the pressure compensation valves,a Power Bond Graph model of the pressure compensation system is built and the corresponding state equations are deduced based on the Bond Graph Theory,theoretical expression of system parameters such as flow area of the valve port and steady flow force are established,which lay the theoretical foundation for the construction of the system simulation platform and trajectory sensitivity analysis.Secondly,a corresponding first-order trajectory sensitivity analysis model is deduced based on the mathematical model of the load-sensing multi-way valve pressure compensation system,the mathematical model of pressure compensation system and the first-order trajectory sensitivity analysis model are solved by using MATLAB dynamic simulation program,the first-order trajectory sensitivity of the main valve port pressure difference to each parameter in the pressure compensation system model is analyzed,the influence of the parameters of the pressure compensation valve on the main valve port pressure is calculated by defining a sensitivity measure and the key parameters affecting the micro-motion characteristics of the main valve are determined.Thirdly,based on the results of sensitivity analysis,the key parameters affecting the main valve port pressure of the pressure compensation valve,such as spring compliance,spring preload,fluid resistance in control chamber,port over-flow area and outlet volume of two-way pressure compensation valve are studied by using the MATLAB dynamic simulation program,and the influence of the key parameters on the micro-motion characteristics of the main valve is analyzed.Finally,based on the multi-function test bed of proportional multi-way valve,a load-sensing proportional multi-way valve experimental system is built,the effect of the pressure compensation valve on the micro-motion characteristics is studied,which verify the correction of the simulation platform. |
PDF Full Text Request