时差法超声波流量计测量精度的补偿方法*

超声波时差法测量精度的提高,不仅使流量计的测量值更加准确,更能满足工业生产监控的智能化及自动化的需求。文中对时差法流量计的测量原理以及影响因素进行分析,结合超声波接收原理,设计了过零检测电路结构,并在顺逆流的时间差的测量问题上,应用互相关算法,完成对时间测量的自补偿。实验结果显示:在采取以上补偿方法后,能有效改善流量计精度,时差测量误差小于0.8%,并提高了测量实时性。

Compensation method for measuring accuracy of transit-time ultrasonic flowmeter

The improved measurement accuracy of the ultrasonic time difference method not only makes the measured value of the flowmeter more accurate, but also meets the needs of intelligent and automated industrial production monitoring. The paper analyzes the measurement principle of compensation method for flowmeter and influencing factors. Combined with the principle of ultrasonic reception, the zero-crossing detection circuit structure is designed, and the cross-correlation algorithm is applied to the measurement of the time difference between the forward and reverse currents to complete the self-compensation for the time measurement. The experimental results show that after the above compensation method is adopted, the accuracy of the flowmeter can be effectively improved, the measurement error of transit-time method is less than 0.8%, and the real-time measurement is improved.