Design Of Ultrasonic Fluid Flowmeters Based On FPGA

The flow measurement is always playing an important role in industrialproduction and daily life. Ultrasonic flowmeters as a new type meters appearing inrecent tens of years are widely used in fields of oil, electronic power, medicine, waterresources management and so on with the features of non-contacting measurement,wide range, simple installment and very suitability for liquid flow measurement ofbig diameters and danger. However, due to the limitation of recent technology, mostof ultrasonic flowmeter productions have common problems like high costs and lowaccuracy which need to have a further development.With FPGA as the signal processing core, this paper detailedly analyzed anddesigned hardware circuit needed by the system. The transmitting circuit of goodperformance matching, the D/A switching circuit, the receiving circuit, the A/Dswitching circuit, the display circuit as well as the storage circuit were designed afterconsidering parameters calculation and devices selection. At the same time, themanipulation of outer devices and the calculation of liquid flow were realized bydesigning stimulating signals generation, high-speed counting, logical control anddata processing module in FPGA’s inner part. Moreover, the design and therealization process of the algorithm of measuring ultrasonic’s transmission time weregiven. This paper used VHDL hardware description language to implement eachmodule’s function and then conducted simulation experiment.Ultrasonic flowmeters based on FPGA develop and improve existing technologyto make productions’ working performance more stable and to have largermeasurement reliability with the help of FPGA’s strong function in data processing,logical calculation and logical control. Developing ultrasonic flowmeter productionswith independent intellectual property can promote enterprise’s comprehensivecompetitive power, have certain guiding significance for ultrasonic flowmeters’further study and create good social and economic benefits as well.