基于时差-脉宽调制法的超声波流量计  

Ultrasonic Flowmeter Based on Time Difference Pulse Width Modulation Method

作　　者：谭超[1] 胡诗俊 苏超 王家成 李宗燎 TAN Chao;HU Shi-jun;SU Chao;WANG Jia-cheng;LI Zong-liao(China Three Gorges University,College of Electrical Engineering&New Energy,Yichang 443002,China;CSIC AnPu(HuBei)Instruments Co.,Ltd,Yichang 443000,China)

机构地区：[1]三峡大学电气与新能源学院,湖北宜昌443002 [2]中船重工安谱(湖北)仪器有限公司,湖北宜昌443000

出　　处：《仪表技术与传感器》2018年第4期55-59,108,共6页Instrument Technique and Sensor

摘　　要：论文设计了一款基于时差-脉宽调制法的超声波流量计。鉴于阈值法超声波流量计误识别第一波而引起测量不准确的问题,在研究基于时差法的超声波测量原理的基础上,提出将时差测量转化成脉冲宽度的测量,避免了复杂工业环境中流量计识别超声回波第一波误差问题;在分析检测原理的基础上,以MSP430F435单片机为核心,结合时差-脉宽调制电路和脉宽-电压转换电路,完成了系统硬件设计。实验结果表明:在较强噪声环境中,该流量计测量精度可达1%,达到了工业用仪器仪表0.5级的精度等级。This paper presented an ultrasonic flowmeter based on time difference-pulse width modulation method.The threshold flow meter had a misidentification of the first wave problem,causing the time measurement error.On the basis of studying the principle of ultrasonic measurement of time difference method,this paper put forward the measurement of time difference measurement into pulse width measurement,which avoids the first wave error of ultrasonic echo identification in flowmeter in complex industrial environment.In this paper,based on the analysis of the principle of detection,the MSP430F435 single chip microcomputer as the core,combined with the time difference-pulse width modulation circuit and pulse width-voltage conversion circuit,the system hardware design was completed.The experimental results show that the accuracy of the flowmeter can reach 1%in the strong noise,reaching the industrial instrumentation level of 0.5 grade accuracy.

关 键 词：超声波 流量计 阈值法 首波识别 脉宽调制 电压转换 

分 类 号：TH815[机械工程—仪器科学与技术]