基于气体超声波流量计的间歇激励和信号处理

Intermittent excitation and signal processing based on ultrasonic gas flowmeter

为了提高气体超声波流量计系统的响应速度,提出一种新的基于相邻峰值最大差值的气体超声流量计信号处理方法。为了进一步提高该信号处理方法的测量精度,又提出一种新的间歇式激励方法。采用间歇式激励方法能得到相邻峰值差值较大的回波信号,并且在不同流量下,相邻峰值最大差值的相对位置始终保持不变。在实际测量中,通过回波信号中相邻峰值最大差值的位置,确定回波信号的到达时刻,进而计算出超声波传播时间,得到气体流量。将间歇式激励方法和基于相邻峰值最大差值的信号处理方法在硬件系统上进行实时实现,并进行标定实验,结果验证了激励方法配合信号处理方法的高效性。

To raise the response speed of the uhrasonic gas flowmeter system, a new signal processing method of uhrasonic gas flowmeter is proposed according to the maximum difference value of adjacent peak. In order to improve the measurement precision of this signal processing method, a new kind of intermittent excitation method is presented. The intermittent excitation method is adopted to obtain the echo signal with the maximum difference value of adjacent peaks. The relative position of the maximum difference value of adjacent peaks in the echo signal is always the same under different flow rates. During the actual measurement, the position of the maximum difference value of adjacent peaks is utilized to determine the arrival time of the echo signal, and then the ultrasonic propagation times are calculated to obtain the gas flow rate. The intermittent excitation method and the signal processing method based on the maximum difference value of adjacent peaks are realized on the hardware system in real time. The calibration experiments are conducted to verify the effectiveness of the excitation method and the signal processing method.