Design Of Virtual Instrument And Parameter Calibration System For Flowmeter Production

In the global environment of advocating the Internet of everything,automated production and real-time monitoring have become the main direction of scientific and technological development.Flowmeter as an important product of automatic real-time monitoring and early warning,has a wide range of applications in daily life,small to domestic water,large to natural gas transportation can see its figure.It can be said that it is just like the traffic police on the road,monitoring and collecting the various parameters of the detected system,so that it can operate more accurately within the expected range.With the wide application of flowmeters,the market demand for flowmeters is increasing,which puts forward higher requirements for the batch calibration speed of flowmeters.Due to the subtle difference of the sensor,the traditional flowmeter calibration process has many shortcomings such as long calibration time cycle,high requirements for the professional degree of the calibration personnel and poor calibration effect.Based on the ultrasonic flowmeter successfully developed by the teaching and Research Office,a flowmeter calibration system is developed by using virtual instrument,MySQL and STM32 as the core controller.Specifically,the following work was completed in the project:1.Use the RS232 communication of the flowmeter to communicate with the host computer,complete the real-time display of the parameters of the flowmeter by the host computer,and use the host computer to deliver the calibration parameters of the flowmeter,and then modify the calibration parameters of the flowmeter.2.STM32F103 EV is selected as the core controller,AD9220 and the designed filter circuit are used as the data acquisition system,and W5500 module is selected as the network transmission module to realize the network transmission between the acquisition circuit and the host computer,and the waveform display interface of the host computer is used to display the collected waveform.And the realization of waveform analysis,the measurement of the waveform of the time class parameters and amplitude class parameters,convenient waveform analysis.3.The interconnection between the host computer and MySQL is realized.Use MySQL to store calibrated historical parameters,and store parameters as well as repeatability errors between actual and expected values.And in the case that the scaler is not sure of the optimal parameter,the historical record can be queried to find the optimal parameter of the historical theory to calibrate the flowmeter.4.Using LabWindows/CVI to complete the development of upper computer,and realize the parameter display and modification function,database query system,parameter display interface and the design of virtual oscilloscope,the virtual oscilloscope functions include parameter measurement,cursor measurement,waveform display and gain adjustment,TCP network communication and other functions.Finally,based on the above work,the calibration system is used to calibrate the flow meter,which shows that the calibration system greatly reduces the technical level requirements of the calibration personnel and realizes the rapid calibration of the flow meter by the technical personnel.