基于希尔伯特变换的科氏流量计信号处理

针对科氏流量计输出的时变信号处理,研究采用基于希尔伯特变换的数字信号处理方法。先后通过多相抽取滤波以及IIR型椭圆带通滤波器对科氏流量计传感器信号进行滤波,再结合信号及其希尔伯特变换,构建原信号的解析信号,通过共轭相乘计算两信号间的相位差,实现流体质量流量的测量。对多种实现希尔伯特变换的方法进行总结优化和仿真比较,仿真和实验结果表明该方法实时性好,满足计量要求。

Signal Processing for Coriolis Mass Flowmeter Based on Hilbert Transform

In order to process the time-varying output signals of Coriolis mass flowmeter, the method based on Hilbert transform is adopted and investigated. Polyphase decimation filter and band-pass filter are applied to filter out noise respectively, then the original signal is combined with the output of its Hilbert transform to build the analytic signals. By co-conjugate multiplying them the phase difference is calculated, and the fluid mass flow measurement is implemented. A variety of methods are summarized and optimized to realize the Hilbert transform,while simulations are carried out for comparing them. The simulation and experimental results show that the method gets a good real-time performance and meets the measurement requirements.