基于静态峰值分布的超声波回波信号检测方法研究  

Research on ultrasonic echo signal detection method based on static peak distribution

作　　者：冯伦宇 张志君 李跃忠[1,2] 葛城轩 FENG Lunyu;ZHANG Zhijun;LI Yuezhong;GE Chengxuan(School of Mechanical and Electronic Engineering,East China University of Technology,Nanchang 330013,China;Jiangxi New Energy Technology and Engineering Research Center,Nanchang 330013,China)

机构地区：[1]东华理工大学机械与电子工程学院,江西南昌330013 [2]江西省新能源工艺与工程技术研究中心,江西南昌330013

出　　处：《中国测试》2023年第1期43-49,共7页China Measurement & Test

基　　金：国家自然科学基金(61663001);江西省教育厅科技项目(GJJ170456,GJJ200173);江西省新能源工艺及设备工程术研究中心开放基金(JXNE2018-08)。

摘　　要：超声波气体流量计在气体流量计量方面具有独特的优势而被广泛应用,然而超声波信号在管道内传播,受流速、噪声等因素的影响,超声波回波信号幅值会发生衰减,造成回波信号定位错误导致严重的计量误差。尤其在高流速情况下,使用常用的方法很难确定特征点,导致测量到错误的结果。为此,研究超声回波信号的峰值特性,提出一种基于归一化静态峰值分布的超声波回波信号的超声气体流量计数字信号处理方法。在静态条件下对超声回波信号进行归一化,提取超声波回波信号峰值分布得到静态峰值参考波。在动态条件下,判断回波信号峰值的与静态峰值参考波的对应关系,确定特征点后计算超声波传播时间。该数字信号处理方法在以MSP430微控制器为核心的数字系统中实现,并进行气体流量标定实验,可验证该方法和所开发的数字系统的有效性。Ultrasonic gas flowmeter has unique advantages in gas flow measurement and is widely used.However,the ultrasonic signal propagates in the pipeline and is affected by velocity,noise and other factors,the amplitude of ultrasonic echo signal will attenuate,resulting in the positioning error of echo signal and leading to serious measurement error.Especially in the case of high flow rate,it is difficult to determine the characteristic points by using common methods,resulting in the measurement of wrong results.Therefore,the peak characteristics of ultrasonic echo signal are studied,and a digital signal processing method of ultrasonic gas flowmeter based on normalized static peak distribution of ultrasonic echo signal is proposed.The ultrasonic echo signal is normalized under static condition and the peak distribution of ultrasonic echo signal is extracted to obtain the static peak reference wave.Under dynamic conditions,the corresponding relation between the peak value of echo signal and the reference wave of static peak value is judged,and the propagation time of ultrasonic wave is calculated after the characteristic point is determined.The digital signal processing method is implemented in a digital system with MSP430 microcontroller as the core,and the gas flow calibration experiment is carried out to verify the effectiveness of the method and the developed digital system.

关 键 词：气体超声流量计 回波信号 归一化 静态峰值分布 

分 类 号：TB9[一般工业技术—计量学] TH701[机械工程—测试计量技术及仪器]