Research On Performance Testing And Analysing System Of Electro-hydraulic Proportional Directional Valve

Electro-hydraulic proportional directional valve is a kind of important electro-hydraulic proportional control element, it's very meaningful to design high performance testing system which both can test and analyze the characteristics of electro-hydraulic proportional directional valve. In this dissertation, on the basis of analyzing the characteristics and test requirement of electro-hydraulic proportional directional valve, a kind of integrated computer aided test system was established, fault and performance analyzing system, based on knowledge reasoning, was promoted, both the above-mentioned system were tested. The chapters of this dissertation are organized as follows.In Chapter 1, the development history of electro-hydraulic proportional technology was discussed, the development status at home and abroad of hydraulic test system and test technology was described, the significance of using CAT to test the the characteristics of electro-hydraulic proportional directional valve was dicussed, then the frequently-used performance analysis method and it's principle was analysed.In Chapter 2, the static and dynamic characteristics of the various components of electro-hydraulic proportional valve were described, such an the proportional electromagnet, the static and dynamic performance test items, test theory, the meaning of the performance indicators and calculation methods of electro-hydraulic proportional valve in the new national standards were researched.In Chapter 3, the overall scheme of electro-hydraulic proportional directional valve test system was presented. A kind of CAT scheme, PC+PLC+touch screen, was proposed. The problem of high-speed, real-time test data collection of dynamic testing process was resolved by using the method of DLL based on Windows operating system, the frequency test method of electro-hydraulic proportional directional valve was researched.In Chapter 4, on the basis of Chapter 3, the hydraulic system and CAT system were achieved, the PC software and PLC software were programed, the anti-jamming measures of the test system were achieved; a part of the performance test results were analyzed, which verified the practicality and reliability of the developed test system.In Chapter 5, the general defects and failure modes of electro-hydraulic proportional directional valve were discussed, the performance analysis expert systems, based on knowledge reasoning was proposed.The main conclusions and achievements are summarized in Chapter 6, and the further research work is put forward.