格型陷波器和DTFT科氏流量计信号处理方法

Signal Processing Method for Coriolis Mass Flowmeter Based on Lattice Notch Filter and DTFT

频率、幅度和相位均按随机游动模型变化的时变信号模型,更为真实地描述科氏流量计信号的实际特性。基于时变模型,提出用于科氏流量计的信号处理方法。采用自适应格型陷波器对频率、幅度和相位均按随机游动模型变化的科氏流量计信号进行滤波,得到频率及增强信号;通过短窗截取,采用DTFT法计算2路信号的相位差和时间差。仿真结果表明,方法具有很好的跟踪效果,且计算量小,可用于科氏流量计的实时信号处理。

A novel signal processing method for Coriolis mass flowmeter is proposed based on time-varying signal model. First, an adaptive lattice notch filter is applied to filter the output signal, whose frequency, amplitude and phase are time-varying based on the random walk model, of Coriolis mass flowmeter to get its frequency and enhanced signal. Then, by short window intercepting, the DTFT algorithm with negative frequency contribution is introduced to calculate the real-time phase difference between two enhanced signals. With the frequency and the phase difference, the time interval between two signals is calculated. Simulation results show that the proposed method is efficient. Furthermore, the computation of algorithms is simple so that it can be applied to real-time signal processing for Coriolis mass flowmeter.