基于数字频谱与模拟带通滤波组的两线制涡街流量计  

Two-wire Vortex Flowmeter Based on Digital Spectral Analysis and Analog Band-pass Filter Group

作　　者：徐科军[1,2] 刘三山[1] 刘家祥[1] 罗清林[1] 

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业技术研究中心,安徽合肥230009

出　　处：《计量学报》2011年第1期25-30,共6页Acta Metrologica Sinica

基　　金：国家自然科学基金（61074164）;美国德州仪器公司创新基金资助项目

摘　　要：基于MSP430F1611单片机，采用数字频谱分析与模拟带通滤波器组相结合的方式，研制新型两线制数字涡街流量计，以扩展量程比，保证现场测量精度，并实现低功耗工作，解决目前此类流量计存在的关键性技术问题。采用低功耗运放和数字电位器组成程控放大器，以适应涡街传感器输出信号强度较大范围的变化；根据少点数FFT计算结果，选择带通滤波器组，既满足涡街传感器信号频率范围变化大的需要，又对涡街信号进行最佳滤波；设计有效的电源管理模块和电流输出电路，为仪表两线制工作提供足够的电流。Combining digital spectral analysis with analog band-pass filter group and adopting the micro-control unit MSP430F1611, a novel digital vortex flowmeter with the two-wire output is developed, which can the measuring range, ensure the measurement accuracy in fields, and operate in low-power. It solves the key technique problem in this kind of flowmeters. A programmable amplifier is constructed by an amplifier with low-power and digital potentiometers in order to adapt large change of amplitude of vortex sensor output. A band-pass filter group is selected by the computation result of small number FFT to cover the variation range of vortex frequency and perform optimal filter for the vortex signal. A power management module and current output circuit are designed to provide enough electrical current for meter operation with two-wire.

关 键 词：计量学 涡街流量计 低功耗 两线制 单片机 数字信号处理 

分 类 号：TB937[一般工业技术—计量学]