The Testing System Of Oil-Free Scroll Compressor Dynamic Characteristic Parameters Based On LabVIEW

As a new high performance displacement compressor, scroll compressor hascharacteristics of compact structure, smooth running and low noise. The scrollcompressor has unique advantages compared with other types of compressors in manyfields. With the development of modern manufacture techniques, it has been more andmore widely applied, from refrigeration and air conditioning to oil-free felids, such asmedicine, food and fuel cell. Because of its own structural features and specificmovement way, the dynamic characteristic parameters are reflection of the workingperformance of the important. For real measuring oil-free scroll compressor dynamiccharacteristic parameters, the system for dynamic characteristic parameters test andanalysis is developed in this thesis，which based on PC hardware platform, laboratoryvirtual instrument workbench(LabVIEW) developed by National Instruments assoftware development platform, essential sensor, signal regulation circuit and dataacquisition card.In this paper the key research oil-free scroll compressor dynamic characteristicparameters of the test bed design. Hardware and software of the system design.Formulae for the suction volume, discharge volume, build-in volume ratio are set upbased on the geometric characteristic of scroll teeth. Design mechanical structure ofthe test device based on comprehensive analysis compressor structure and the workingprocess of the influence of compressor performance various factors. First, simpleintroduction all virtual instruments are made in my thesis. Second, the theories ofsignal analysis and signal acquisition are analyzed. Last, hardware and softwareprogramming of measurement system are designed．The superincumbent modulardesign is exhibited evidently in the software system, the signal sampling and dataanalysis are operated by system interface, as well as the result are displayed on thecomputer screen. The main function of the test software is made up of fixed andorbiting plate faces frictional temperature test module, friction test module, Vibrationtest module, axis locus test module. The content involves digital Filter, Windowing,Time Domain Statistical analysis, Auto Correlation analysis, Cross Correlationanalysis, as well as Fast Flourier Transfer, Auto Power Spectrum analysis, Short-timeFlourier Transfer are included in the analysis program． Experiment shows that, test system can realize the function of each test module,have high feasibility and reliability. The results show that, compared with thetraditional signal acquisition system, data acquisition system based on the LabVIEWhas low cost, friendly interface, short development cycle, easy mainten ance and itsdata processing is simple and convenient. This is great significance for characteristicanalysis, theory design and improved the performance of oil-free scroll compressor.