超声波传感器谐振规律的实验研究

由于晶体超声波谐振子泛音的存在,谐振频率点并不唯一。而超声波测量系统频率的选择至关重要。为确定用于流量测量的超声波传感器的谐振频率,设计了实验测试方案,即用函数信号发生器给发射传感器输入幅度相同、频率不同的方波激励信号,用示波器观测接收传感器输出信号,记录接收探头随频率递增时,幅度较大极值点所对应的频率。然后,以数据拟合的方法寻求晶体超声波谐振子各谐振频率点分布的规律。实验结果表明：根据这些幅度较大极值点寻求的谐振频率点分布的拟合线,基本符合一般极值点对应频率的分布规律,反过来证明了研究所得的该种传感器谐振频率点分布规律的正确性,这为流量测量中超声波频率设定提供依据。

Experimental Study for the Resonance Law of the Ultrasonic Sensor

Because of the ultrasonic resonator overtone,the resonant frequency of ultrasonic sensor is not unique. It is critical for the ultrasonic measurement system frequency selection. To determine the resonant frequency of the ul-trasonic sensor for flow measurement,a test program is designed,which are using function signal generator to input the same sensor amplitude and different frequency square wave,as the excitation signal,and using an oscilloscope to observe the receive-sensor output signal,then record the receiving probe with the frequency increasing,the lar-ger amplitude in the extreme points corresponding frequency. Moreover,for seek the law of distribution about each crystal resonator resonant frequency by data fitting method. The experimental results showed that the fitted line ask-ing these extreme magnitude larger resonant frequency distribution,in line with the general distribution of extreme points corresponding frequency,which in turn proves the Institute was kind of sensor resonant frequency distribution rule is correctness,which provide the basis of settings ultrasonic frequency for flow measurement.