Electro-hydraulic Servo Valve Test System

Electro-hydraulic servovalve is the part of high precision with the combination of the mechanical, electronic, and hydraulic technology, electro-hydraulic servovalve is the key component of electro-hydraulicservoystem the performance of which has direct efects on or even determines the performance of the entire electro-hydraulic servo system.The characteristic of electro-hydraulic servovalve includes two respects of the stable state characteristic and dynamic characteristic. Main stable state performance has characteristic of flow with loads, unloaded flow characteristic, pressure characteristic and inside leakage characteristic;Main dynamic performance is as follows,frequency response characteristic and steps response characteristic.In addition, because servovalve often works in zero areas,so the zero areas characteristic is very important,involving zero excursion and zero float characteristic, zero point threshold value and discernment ratio.Firstly, the test method and principle of electro-hydraulic servo valve were studied in this dissertation, It mainly introduces the capability standard of electro-hydraulic servovalve static and dynamic state characteristic and it also tells the basic theory of test principle, data acquisition and signal processing.Secondly,this paper studys the scheme of electro-hydraulic servovalve static and dynamic state characteristic test system,the paper conducts the hardware designing of the testing system,which mainly complete the configuration of various kinds of hardware in the system .The paper also does researches on the peripheral problems of the testing system, such as the composition of the hydraulic part of the testing system of the electro-hydraulic servovalve and its control,the anti-jamming design of the testing system, hydraulic system pollution control ,etc.,to provide insurance for the reliable operation of the testing system.Thirdly, detailed analysis was done in the elements of the dynamic state testing system, through the study on the main component and principle, and the mathematics models of every elements and the displacement-feedback system were founded,and then the emulation of system characteristic property and the performance of the servovalve was carried on based on the modelsin the MATLAB and AMESim software At last,the testing system is adopted for the static and dynamic characteristic tests on SFL-14B electro-hydraulic servovalve, the tested results are analyzed and the causes of the error have been found out.The paper also drew the conclusion,and prospected in the future.