透镜式聚焦压电换能器超声功率测试分析

Ultrasonic power measurement and analysis of lens style focused piezoelectric transducer

从声学原理出发推导了作用于锥面反射靶的超声功率和辐射压力之间的关系，在此基础上设计了一种新型超声功率计，该超声功率计采用反射靶加吸收靶的结构形式，避免了反射声束之间的相互干扰．用校正螺母对该功率计进行了校准和误差分析，并采用3个不同角度的反射靶对该声功率计进行了验证．理论分析和实验表明：在0—200W的测量范围内，采用3个不同角度的反射靶测量结果基本吻合，最大相对误差为10％左右；被测量的透镜式聚焦压电换能器的电功率、声功率随着驱动电压的升高而增大，且声功率增加逐渐变缓，呈一定的非线性．

A novel ultrasonic power meter is designed according to the relationship between ultrasonic power and radiation pressure deduced from ultrasonic theory, it utilizes the structure of reflecting target plus absorbing target, which prevents the sound beam from intervening. It is calibrated by weights and validated by the reflecting targets with three different angles. The results demonstrate that the measuring results of reflecting targets with three different angles agree within the calibrated range of 200 W. And the overall uncertainty of the measuring results is below 10%. Also the results show that the electric power and the ultrasonic power of the transducer rise along with the driving voltage, while the increase of the ultrasonic power gradually shows down, showing a nonlinear character.