管道传输气体超声波流量计的新设计方法  

New Design Method of Ultrasonic Flowmeter for Pipeline Gas Transmission

作　　者：董雅琳 裴小静 刘涛[1] 仲崇权[2] DONG Ya-lin;PEI Xiao-jing;LIU Tao;ZHONG Chong-quan(Institute of Advanced Control Technology,Dalian University of Technology,Dalian 116000,China;Institute of Computer Control and Information Technology,Dalian University of Technology,Dalian 116000,China)

机构地区：[1]大连理工大学先进控制技术研究所,辽宁大连116000 [2]大连理工大学计算机控制与信息技术研究所,辽宁大连116000

出　　处：《控制工程》2020年第12期2210-2218,共9页Control Engineering of China

基　　金：国家自然科学基金(61633006);辽宁省兴辽英才计划项目(XLYC1902030)。

摘　　要：采用超声波技术检测工业管道流量是一种新发展的流量测量方法,由于超声波在气体中传播衰减较大,易受到环境的干扰,现有的超声波检测方法难以保证测量精度。基于时差法测量原理,提出了一个新的X型超声波气体传感器设计方案,通过使用三阈值电路对接收到的超声波信号进行检测点校正,可降低由超声波缺波与陷波造成的测量误差,从而提高测量精度。采用小波阈值滤波方法对测量得到的超声波飞行时间进行数字滤波,以提高抗噪和检测信号稳定性。并且给出一个MALLAT快速算法以实现小波分析在单片机上实时应用。通过在一个组装的单片机实时检测装置上进行气体流量测试,有效地验证了所提出的设计方法的准确性和可靠性。The use of ultrasonic technology for detecting industrial pipeline flow is a newly developed flow measurement method.Because the ultrasonic wave is largely attenuated in the air and easily affected by environmental disturbances,the existing ultrasonic detection methods could hardly guarantee the measurement accuracy.Based on the time difference principle for ultrasonic measurement,this paper proposes a new X-type sensor design scheme.A three-threshold circuit is used to rectify the detected points of the received ultrasonic wave,the measurement error arising from the ultrasonic wave loss and/or notch can be reduced,and therefore,the measurement accuracy can be further improved.The wavelet threshold filtering method is used to digitally filter the measured flight time of ultrasonic wave,so as to improve anti-disturbance performance and stability of measured signal.Moreover,a fast algorithm named MALLAT is given to implement the wavelet analysis on a single-chip microcomputer for real-time application.Real-time measurement tests are made for the gas flow based on an assembled single-chip microcomputer,which effectively demonstrate the accuracy and reliability of the proposed design method.

关 键 词：气体超声波流量计 超声波检测 时差法测量 三阈值比较法 小波分析 

分 类 号：TP29[自动化与计算机技术—检测技术与自动化装置]