科氏流量计测量管固有频率在线预测方法

摘要

提出了一种基于幅值变化期信号特征参数识别的科氏流量计测量管固有频率在线预测方法,该方法对测量管固有频率变化时引发的过渡期振动信号进行两次整周期采样,进而通过傅里叶变换获得反映所采样信号特征的虚部与实部参数,并根据所建立的基于信号特征参数的固有频率改变量计算模型,计算出测量管当前固有频率.对所提出方法进行了实验验证.该方法可用于科氏流量计振动控制中,帮助其将驱动频率快速、精准地调整到固有频率上,从而提高科氏流量计在复杂多变工况下的测量可靠性.%A tube natural frequency online determination is presented based on amplitude of signal characteristic parameters identification for the Coriolis flowmeter (CMF).The transition period of vibration signal that caused by the natural frequency of vibration signal measurement tube changed,is whole period sampled twice.The method obtains the imaginary and real part of parameters containing the sampled signal characteristics through the Fourier transform,and the natural frequency of the measuring tube is calculated according to the calculation model based on the natural frequency of the signal characteristic parameters changing.The proposed method is verified by the experiment,and the method can be used in vibration control of Coriolis flowmeter,helpping the driving frequency quickly and accurately adjusted to the natural frequency,so as to improve the Coriolis mass flowmeter in the complicated and changeable conditions of measurement reliability.