用门延迟法提高超声波流量计的测量精度

摘要

A New method was presented to achieve accurate time-interval. Through measuring the transmission delay gate circuit of CPLD in internal,an accurate flow measurement in small size pipeline and low flow occasion was realized. The accurate measurement of temperature was reached by measuring the discharge time of circuit. The experiment has proved that its accuracy can reach 300ps. This method has more accuracy and less error calculation than the common one. This method also meets the requirement of low consumption.%提出一种精确测量时隙间隔的新方法.通过CPLD内部门电路的传播延迟来进行高精度时间间隔测量,从而实现了小管径、低流速情况下的高精度流量测量.通过测量不同放电回路的放电时间,从而实现了对温度的高精度测量.实验证明其测时隙的精度可达300 ps.该方法比现在常用测量法具有更高的测量精度,更小的测量误差.由于该方法的特点,所以保证了对低功耗的要求.