基于虚拟仪器的超声换能器阻抗分析仪设计

A Design of Ultrasonic Transducer Impedance Analyzer Based on Virtual Instrument

利用常规的信号发生器、数字示波器等测量仪器,结合计算机控制原理,从导纳圆图法测量换能器阻抗特性参数的原理出发,基于虚拟仪器的设计方法,通过计算机控制信号发生器产生换能器的激励信号,经信号调理电路处理,数字示波器采集换能器工作时的电压及电流,分析换能器的电流和电压信号及其相位差,求出阻抗特性参数。多组实验数据显示,设计的系统基本上达到了商用仪器的测量精度,能测量换能器主要特性参数,开发成本低,拓展了超声换能器性能参数的测量方法。

Utilizing the conventional signal generator,digital oscilloscope and other measuring instruments,combining with the computer control theory,using the theory of admittance circle diagram to measure the transducer impedance parameters,and based on the design method of the virtual instrument,we can get the impulse signal through the signal generator,which is controlled by computer.After being processed by the signal conditioning circuitry,the digital oscilloscope gathers the voltage and current during the transducer working,then the current and voltage signals as well as the phase difference of the transducer were analyzed,then the impedance parameters were calculated.The multiple sets of experimental data showed that the proposed system has achieved the measuring accuracy of the commercial instrument basically and the main characteristics parameters of the transducer can be measured.The proposed system is characterized by the feature of low development and expanding the measurement method of the ultrasonic transducer performance parameters.