基于数字滤波与自相关的涡街流量计抗强振动方法改进  

Improvements of Anti-strong-vibration Method Combing Digital Filter with Auto-correlation for Vortex Flowmeter

作　　者：徐科军[1,2] 王沁[1] 方敏[1] 邵春莉 

机构地区：[1]合肥工业大学电气与自动化工程学院,安徽合肥230009 [2]工业自动化安徽省工程技术研究中心,安徽合肥230009

出　　处：《计量学报》2014年第5期449-454,共6页Acta Metrologica Sinica

基　　金：国家自然科学基金（61074164）;致谢：感谢重庆川仪自动化股份有限公司提供实验条件和涡街流量计一次仪表.

摘　　要：涡街流量计容易受到管道振动的干扰，对测量精度造成较大影响，特别是当振动噪声的功率大于涡街信号的功率时，采用通常的数字信号处理方法也无法得到正确的涡街频率。为此，提出将数字滤波和自相关相结合的算法，运用于涡街流量传感器的信号处理，从含有强振动干扰的信号中识别出流量信息。针对该方法在实际实现中遇到的问题，对已有系统软件进行改进和完善。基于MSP430F5418单片机，使用汇编语言编制实数FFT算法实现了自相关函数的运算。Vortex flowmeter is susceptible to the interference of pipe vibration, which affects on the measurement accuracy greatly. Adopting normal digital signal processing methods cannot obtain the accurate vortex frequencies when the power of vibration noise is larger than that of the vortex signal. Therefore a digital signal processing technique combining digital filter with autocorrelation was proposed to apply the signal processing of vortex flow sensor for extracting the flow rate information from the signal containing strong vibration interference. Aiming at the implementing problems of this method in practice application, the existing system software is improved. The autocorrelation function is calculated by using real number FFT algorithm with assemble language based on MSP430F5418 MCU in order to speed up computation.

关 键 词：计量学 涡街流量计 数字滤波 自相关 强振动干扰 FFT 单片机 

分 类 号：TB937[一般工业技术—计量学]