采用梳状带通滤波的电磁流量计信号处理系统

Digital signal processing system for electromagnetic flowmeter with comb-shaped band-pass filter

提出采用梳状带通滤波和幅值解调的方法,处理高频矩形波励磁下电磁流量传感器输出信号,有效地抑制了各种噪声的干扰。对算法进行了仿真研究,确定梳状带通滤波器的带宽。选用DSP芯片,研制了数字信号处理系统,实时实现上述处理算法。进行了水流量标定实验,结果表明本文所研制系统的测量精度优于0.3%,满足工业测量的要求。

Comb-shaped band-pass filter and amplitude demodulation are used to deal with the output signal of the electromagnetic flowmeter under high frequency square wave exciting mode for suppressing noises effectively. The simu- lations of the algorithm are carried out by Maflab to determine the bandwidth of the filter. A digital signal processing sys- tem is developed with DSP chip, and the algorithm is implemented in real time. The calibration experiment of water flow is performed, and the results show that the measurement accuracy is better than 0.3%, which satisfies the requirements of industrial measurement.