Cat Theories And Experiments Study On Electro-hydraulic Servo Valve Static And Dynamic State Characteristic Test Based On Virtual Instruments

Electro-hydraulic servo valve test is of very importance in scientific research and engineering. The application of computer-aided test (CAT) provides a brilliant future for characteristic test of servo valve and the technique.~of virtual instruments brings CAT into a new developing stage. This dissertation applies virtual instruments technique in the field of servo valve CAT for the first time and makes a servo valve static and dynamic state characteristic test bedstand based on virtual instruments. Relevant theories and methods are also studied. Characteristic of FF102 servo valve is tested and its results are analyzed.The relevant theories ii Jude data acquisition and processing, signal and system, digital signal processing, automatic control, instruments and electronics, hydraulic transmission and control, machining.This dissertation makes an attempt in the loading methods on servo valve and replaces the common throttle valve with a proportional throttle valve. As the computer controls the throttle valve, this method gets rid of the hand randomization, shortens the testing time, lightens the work of lab assistants and makes a progress towards the automatic test. In the pressure characteristic test, a new method of testing pressure difference is brought out. With an entire bridge circuit and two pressure sensors, the structure is simple but the result is of high precision. In the leakage characteristic test, the problem of small leakage flow automatic test is solved with the method of usage of an ellipse gear flow meter and a self-made interface circuit. In the dynamic state characteristic test, frequency sweeping and statistic methods are used and their results are compared with 1250 frequency response analyzer.?1?AbstractThe prevailing virtual instruments programming software 棗LabVIEW 5.11 is used with Windows 98 operating system. The interface is friendly and program structure is clear and easy to maintain. As virtual signal sources produces all the stimulating signals and virtual instruments performs all the testing functions, this testing system saves real instruments and lowers the expenditure.