基于IIR小波滤波器的涡街流量计数字信号处理系统  

Digital signal processing system based on IIR wavelet filter for vortex flowmeter

作　　者：黄云志[1] 徐科军[1] 

机构地区：[1]合肥工业大学自动化研究所

出　　处：《仪器仪表学报》2007年第12期2142-2146,共5页Chinese Journal of Scientific Instrument

基　　金：国家863计划(2007AA04Z180)资助项目

摘　　要：涡街流量计被广泛应用于过程工业,但是,由于易受由管道振动和流场扰动等因素干扰,现场测量精度无法保证,测量小流量困难。本文将小波滤波器组应用于涡街流量计信号处理中,研究基于小波滤波的涡街信号处理方法,分析了小波滤波器的幅频特性对信号分析的影响,构造了幅频特性好的IIR型小波滤波器组。本文研制了基于ADSP2181的涡街流量计数字信号处理系统,并进行了气体流量和水流量标定实验,实验结果表明,基于小波滤波的涡街流量计数字信号处理系统有良好的适配性能,性能指标优于常规的涡街流量计处理系统。Vortex flowmeter is widely used in process industry. However, it is subjected to noise disturbance caused by pipe vibration and fluid turbulence. The measurement accuracy in the field cannot be ensured, and also the low velocity flow is difficult to be detected. This paper applies wavelet filter to the signal processing of vortex flowmeter. A digital signal processing method based on wavelet filter is studied, the influence of its frequency response on signal processing is analyzed, and Butterworth wavelet filter with good amplitude-frequency characteristic is constructed. A real-time digital signal processing system was developed based on a DSP chip ADSP2181, and calibrations experiments for gas and water flow rates were performed, respectively. Experimental results show that the digital signal processing system with wavelet filter possesses better performance and adaptability than those of conventional signal processing system.

关 键 词：涡街流量计 小波滤波 IIR滤波器组 信号处理 

分 类 号：TH814[机械工程—仪器科学与技术] TP23[机械工程—精密仪器及机械]