Research On Intelligent Active Test Theory And Method Of Hydraulic System

Hydraulic system is characterized by high power density,quick response and high precision.It is the most widely used driving mode and the heart of control and power transmission of various kinds of equipment in the fields of heavy industry,light industry,agriculture,forestry,fishery,navigation,aerospace and military industry.With the combaination of mechanical,electrical and hydraulic field,the hydraulic equipment structure is more and more complex,and its function is more and more powerful,resulting in the difficulty of observing and testing hydraulic health problems and fault.If a misdiagnosis occurs,it will cause immeasurable economic losses.In order to improve the working reliability of hydraulic system,domestic and foreign industry experts are committed to the quick and accurate hydraulic system fault testing and method research.They develop a variety of instruments or device of hydraulic system diagnosis methods,basing on different principles,structures,characteristics.However,a considerable part of those research work is still theoretical research and laboratory experiments.In real hydraulic context,energy-saving and intelligent test instruments are rare.Therefore,developing a new level of hydraulic testing system theory and corresponding methods is an important engineering field.Basing on the current development of oversea and domestic researches,this paper focuses on the theory and methods of hydraulic active test system,which enjoys independent intellectual property right in engineering field,to meet the need of quick and convenitent hydraulic test system.By summing up the commonly used various hydraulic system test technology,the characteristics of those methods,this paper uses AEMSim simulation technology to analyze the defects of the first generation of hydraulic active tester,puts forward an optimized scheme for increasing accuracy of 2nd generation tester which adopts output flow closed loop control system,lays the foundation for more accurate detection for hydraulic system leakage;According to the classification of hydraulic system,this paper also establishes the open and closed loop hydraulic system and carries out corresponding theory research.The attachment library of hydraulic system detection is created,which lays a theoretical foundation for the application of hydraulic intelligent active testing technology.The accurate calculation model of the new testing method of hydraulic system and the relationship with other key parameters are studied,which lays a theoretical foundation for the design and control of the new hydraulic testing device.On the basis of further research,this paper develops the 2nd generation of hydraulic active tester,using MySQL software to build a database of hydraulic leakage components,realizing intelligent active test of hydraulic system leakage,perfecting the theory and method of hydraulic active test.After studying the new adaptation problem of the hydraulic pressure test method and all kinds of hydraulic equipment,intelligent test method is put forward in order to realize high adaptability of hydraulic testing technology,improve the test precision of the hydraulic test equipment.The leakage detection and fault diagnosis of typical hydraulic components,such as electro-hydraulic directional valve,proportional relief valve and axial piston pump,are completed by using hydraulic active testing technology.According to the national standard and other product samples produced by foreign hydraulic components manufacturers,such as parker and rexroth,this paper creats a variety of hydraulic components factory test leakage data,establishing the hydraulic components health leakage database,as well as hydraulic system leakage health intelligent active detection system.The hydraulic intelligent test system is used to detect the leakage health status of the hydraulic system,such as 100 T platform truck,hydraulic straightening cutting machine,forging hydraulic press and China Tian-yan FAST hydraulic actuator group,the availability of the hydraulic active intelligent test system is verified,it can realize to detect rapidly and accurately the hydraulic system leakage health status and various hydraulic fault locations,provides the conditions for scientific maintenance.