超声波流量计的阻抗匹配设计

doi:10.16180/j.cnki.issn1007-7820.2025.03.009

摘要/Abstract

摘要：

为提高超声波流量计测量精度,需要对激励信号源和超声波压电换能器之间进行阻抗匹配,但现有超声波压电换能器的阻抗匹配装置依赖进口,存在操作复杂、灵活性不佳等缺点。为降低制造和维护成本并提升操作的方便性,文中设计了串联电感、并联电感两种阻抗匹配电路。文中设计模拟开关电路实现超声波信号的收发控制,信号放大电路负责放大超声波信号,单片机实现模拟开关电路的通道切换和超声波传播时间的数据采集。仿真结果表明,串联电感阻抗匹配优化了输入信号波形,提高了超声波压电换能器的驱动效率。实验结果表明,串联电感阻抗匹配后,单片机测量的超声波传播时间数据提前了50 μs,提高了超声波传播时间数据的准确性。但是激励信号源内阻较小,因此并联电感阻抗匹配效果不佳。

关键词: 气体流量计量, 超声波时差法, 超声波压电换能器, 阻抗匹配, 等效电路, 谐振频率, 测量精度, 信号分析

Abstract:

To improve the measurement accuracy of ultrasonic flow meters,it is necessary to match the impedance of excitation signal source and ultrasonic piezoelectric transducer. However, the existing impedance matching devices of ultrasonic piezoelectric transducers not only rely on imports but also have the disadvantages of poor operation and flexibility. In order to meet the requirements of low manufacturing, maintenance cost and convenient operation, two impedance matching circuits of series inductor and parallel inductor are designed in this study. An analog switch circuit is designed to realize the transmission and reception control of ultrasonic signals, a signal amplifier circuit is responsible for the amplification of ultrasonic signals, and a single-chip microcomputer is used to realize channel switching of the analog switch circuit and data collection of ultrasonic propagation time. The simulation results show that the series inductor impedance matching optimizes the input signal waveform and improves the driving efficiency of the ultrasonic piezoelectric transducer. The experimental results show that after the series inductor impedance matching, the ultrasonic propagation time data measured by the microcontroller is advanced by 50 μs, the accuracy of the ultrasonic wave propagation time is improved. But the internal resistance of the excitation signal source is small, and the parallel inductance impedance matching effect is not good.

Key words: gas flow measurement, ultrasonic transit-time difference method, piezoelectric transducer, impedance matching, equivalent circuit, resonant frequency, measurement precision, signal analysis

中图分类号:

TN64

扶艺辉, 刘瑜, 肖汉林, 王明杰. 超声波流量计的阻抗匹配设计[J]. 电子科技, 2025, 38(3): 68-74.

FU Yihui, LIU Yu, XIAO Hanlin, WANG Mingjie. Design of Ultrasonic Piezoelectric Transducer Impedance Matching[J]. Electronic Science and Technology, 2025, 38(3): 68-74.

图/表 17

图1

图2

图3

图4

图5

图6

图7

表1

图8

图9

图10

图11

图12

图13

图14

表2

表3

参考文献 18

[1]	赵成海. 我国天然气流量测量技术标准体系的建立[J]. 石油与天然气化工, 2016, 45(1):92-95.
	Zhao Chenghai. Establishment of natural gas flow measurement technical standard system in China[J]. Chemical Engineering of Oil and Gas, 2016, 45(1):92-95.
[2]	王荣晓, 张守阳, 章宦辉, 等. 气体涡轮流量计在不同温度下的计量性能研究[J]. 仪器仪表用户, 2022, 29(11):12-15.
	Wang Rongxiao, Zhang Shouyang, Zhang Huanhui, et al. Research on measurement performance of gas turbine flowmeter at different temperatures[J]. Instrumentation, 2022, 29(11):12-15.
[3]	王杰, 孟然, 陈长江, 等. 天然气回流对孔板流量计上下游截面压力影响分析[J]. 广州化工, 2021, 49(10):127-128.
	Wang Jie, Meng Ran, Chen Changjiang, et al. Analysis on influence of natural gas reflux on upstream and downstream section pressure of orifice flow-meter[J]. Guangzhou Chemical Industry, 2021, 49(10):127-128.
[4]	刘扬, 杜明. 涡街流量计在贸易计量上的应用[J]. 自动化与仪表, 2021, 36(12):99-102.
	Liu Yang, Du Ming. Application of vortex in trade measurement[J]. Automation and Instrumentation, 2021, 36(12):99-102.
[5]	Fabian Manuel B, Septimiu L, Ioan L. Calibration of time-of-flight ultrasonic flow meters[C]. Timisoara: IEEE the Twenty-seventh International Symposium for Design and Technology in Electronic Packaging,2023:358-361.
[6]	Brassier P, Hosten B, Vulovic F. High-frequency transducers and correlation method to enhance ultrasonic gas flow metering[J]. Flow Measurement and Instrumentation, 2001, 12(3):201-211.
[7]	高飞. 超声波流量计诊断技术在天然气计量中的应用[J]. 石油化工自动化, 2020, 56(5):64-67.
	Gao Fei. Application of ultrasonic flowmeter diagnosis technology in natural gas metering[J]. Automation in Petro-chemical Industry, 2020, 56(5):64-67.
[8]	胡之勇. 基于飞行时间差的高精度超声波气体流量计的研究[D]. 郑州: 郑州大学,2022:9-11.
	Hu Zhiyong. Anovel differential time-of-flight algorithm for high precision ultrasonic as flow measurement[D]. Zhengzhou: Zhengzhou University,2022:9-11.
[9]	Chenyu D. Design of anultrasonic gas flow measurement circuit based on the time-difference method[C]. Xi'an:The Third International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field,2021:369-373.
[10]	张锐. 基于时差法的超声波气体流量测量系统的设计与实现[D]. 西安: 西安电子科技大学,2020:13-15.
	Zhang Rui. Design and implementation of the ultrasonic gas wave flow measurement system[D]. Xi'an: Xidian University,2020:13-15.
[11]	李晓, 宋雁鹏, 王志斌, 等. 压电换能器等效模型分析与阻抗匹配设计[J]. 应用声学, 2016, 35(1):13-19.
	Li Xiao, Song Yanpeng, Wang Zhibin, et al. The analysis of a piezoelectric transducer equivalent impedance model and the design of an impedance matching circuit[J]. Journal of Applied Acoustics, 2016, 35(1):13-19.
[12]	施浩然, 孔淑婷, 高桂玲, 等. 功率超声换能器压电元件阻抗匹配装置的设计与制作[J]. 电子设计工程, 2021, 29(21):27-32.
	Shi Haoran, Kong Shuting, Gao Guiling, et al. Design and fabrication of impedance matching device for high power piezoelectric ultrasonic transducer elements[J]. Electronic Design Engineering, 2021, 29(21):27-32.
[13]	王玉江, 王志斌, 宋雁鹏, 等. 压电超声换能器阻抗特性分析与匹配设计[J]. 压电与声光, 2016, 38(4):633-638.
	Wang Yujiang, Wang Zhibin, Song Yanpeng, et al. Impedence characteristic analysis and matching design of piezoelectric ultrasonic transducer[J]. Piezoelectrics and Acoustooptics, 2016, 38(4):633-638.
[14]	韩丽轩, 于保华, 胡小平. 功率超声压电换能器阻抗匹配电路参数化设计[J]. 压电与声光, 2015, 37(4):713-716,720.
	Han Lixuan, Yu Baohua, Hu Xiaoping. Parametric design of impedance matching circuit for power ultrasonic piezoelectric transducer[J]. Piezoelectrics and Acoustooptics, 2015, 37(4):713-716,720.
[15]	徐晓伟. 压电超声换能器的阻抗匹配分析[J]. 压电与声光, 2014, 36(5):745-747.
	Xu Xiaowei. Analysis on the matching impedance of piezoelectric ultrasonic transducer[J]. Piezoelectrics and Acoustooptics, 2014, 36(5):745-747.
[16]	Kredba J, Holada M. Precision ultrasonic range sensor using one piezoelectric transducer with impedance matching and digital signal processing[C].Donostia:IEEE International Workshop of Electronics,Control,Measurement,Signals and their Application to Mechatronics,2017:1-6.
[17]	杨佳婷. 螺栓对压电换能器有效机电耦合系数影响的研究[D]. 西安: 陕西师范大学,2018:23-25.
	Yang Jiating. Research on the influence of bolts on the effective electromechanical coupling coefficient of piezoelectric transducers[D]. Xi'an: Shaanxi Normal University,2018:23-25.
[18]	高岩. 基于匹配电路的低功耗气体超声波流量计激发接收电路研究[D]. 杭州: 浙江大学,2019:27-28.
	Gao Yan. Research of driving and receiving circuit of low-power gas ultrasonic flowmeter based on matching network[D]. Hangzhou: Zhejiang University,2019:27-28.

引脚电平	通道选择	说明
100	A₀	A路连接A₀通道
101	A₁	A路连接A₁通道
11x	A₂	A路连接A₂通道
000	B₀	B路连接B₀通道
001	B₁	B路连接B₁通道
01x	B₂	B路连接B₂通道

温度/℃	匹配后时间/μs
31	172.42	198.62	223.42	248.62	273.42	298.72
31	172.10	198.70	223.30	248.70	273.32	298.82
31	173.05	198.52	223.02	248.62	273.30	298.95
31	173.25	198.55	223.07	248.55	273.42	298.72
31	172.25	198.52	223.37	248.72	273.35	298.75

温度/℃	匹配后时间/μs
31	222.39	248.61	273.35	298.62	323.37	348.76
31	222.12	248.67	273.27	298.71	323.36	348.82
31	223.08	248.44	273.07	298.62	323.32	348.95
31	223.21	248.48	273.02	298.55	323.45	348.74
31	222.20	248.57	273.47	298.77	323.37	348.75