级联自适应陷波器设计及不同步脉冲计数补偿

Design of Cascade-Connection Adaptive Notch Filter and Counting Compensation of Asynchronous Pulses

为减小计数误差及实现多路不同步异频脉冲信号的高精度测量,设计了一款可实时估计周期脉冲信号相位的级联自适应陷波器(CANF).首先在前端固定一自适应因子为0的Liu型自适应陷波器(LANF),然后将LANF的输出作为Mojiri型自适应陷波器(MANF)的输入,再利用MANF的估计频率实时调整LANF,最后在流量计标准装置中实现CANF的相位实时估计,并对两路不同步脉冲信号进行精度补偿.仿真实验结果表明CANF的计数误差小于±0.047个脉冲,工程应用实验结果表明CANF的计数误差小于±0.045个脉冲,说明了文中通过实时计算信号相位进行计数补偿的方法能有效提高脉冲计数检定精度和多路并行检定的实用性.

In order to reduce counting error and implement high-accuracy measurement of multi-channel asynchronous impulse signals with different frequencies,a cascade-connection adaptive notch filter（ CANF） for realtime phase estimation is proposed. In CANF,firstly,an ANF designed by Liu（ LANF） with an adaptive factor of0 is set in the front of ANF,and the output of LANF is used as the input of an ANF designed by Mojiri（ MANF）.Secondly,the estimated frequency of MANF is used to adjust the frequency of LANF in real time. Then,CANF is applied to a multi-station flowmeter calibration equipment and is used to calculate the real-time phase of two channels of asynchronous impulse signal. Finally,simulation and practical application of CANF are carried out,with the corresponding counting errors being less than ± 0. 047 and ± 0. 045, respectively, which means that the counting error compensation via real-time phase calculation effectively improves the counting accuracy of asynchronous pulses and the practicability of multi-channel parallel calibration.