Design And Implementation Of Low Power Consumption Gas Ultrasonic Flowmeter

Natural gas is one of the main energy sources in China,with the advantages of clean,high heat generation and low price,and is an important part of the construction of a clean,low-carbon,safe and efficient system.Scientific and efficient metering is a top priority in all aspects of gas production,supply,storage and marketing.With the development of flowmeter,among the many flowmeter,ultrasonic flowmeter has been developed rapidly in recent years.But with the widespread use of ultrasonic flowmeter,its high power consumption,data transmission difficulties and other problems have also been exposed,and these problems seriously limit the future development of ultrasonic flowmeter.Currently,the ultrasonic flowmeter market is always occupied by foreign products.The measurement accuracy of domestic flowmeter is relatively low and the power consumption is high,which is insufficient in the field of high-precision measurement.In this paper,a low-power,high-precision ultrasonic gas flow meter is designed for low-pressure gas measurement.The flow meter is available in two models for DN50 and DN80 pipe sizes.In this thesis,the principle of time-varying measurement is used,using a two-channel measurement method.Using the C8051F960 microcontroller as the control module core and the TDC-GP22 as the time measurement chip,the ultrasonic flow meter was designed.In the flowmeter design,this paper proposes a low-power design scheme and completes the chip selection and hardware circuit design according to this scheme.According to the size and nature of each signal is different,this paper uses three PCB boards,respectively,the main control board,transceiver board and interface board.In addition,for ease of maintenance,a separate ultrasonic acquisition and emission circuit and a signal processing circuit are designed herein,which are placed on a separate PCB board and connected to the transceiver board via a pluggable interface.Paper adopts a time-sharing program structure,dividing the entire program into multiple modules,running only one function in each time interval,reducing the coupling between programs,so that the power consumption of each part can be intuitively displayed.Multiple time intervals have been set aside to facilitate subsequent system upgrades.The flowmeter was validated and tested using an experimental platform and the power consumption was measured.The flowmeter is calibrated mathematically by error analysis.After calibration,the accuracy level of the flowmeter has reached the national standard 1.0 level and the operating current is 1.265 mA,which is in line with the design index.