一种船用超声液位传感器的优化设计模型

摘要

针对一种船用超声液位传感器数学建模和多目标优化设计的问题,提出了一种基于等效电路和遗传算法的优化设计方法.将电-力-声类比的方法应用到建模中,由此建立了传感器的等效电路模型,并推导出传感器频率和输出特性参数的相关方程.在等效电路模型的基础上,以压电陶瓷尺寸、保护膜厚度和工作间隙为设计变量,以输出电压的峰-峰值和信号特征值为优化目标,建立了超声液位传感器的多目标优化模型.采用遗传算法(GA)进行优化计算,并利用MATLAB和GA优化工具箱进行求解.实例分析表明,优化后传感器性能得到了显著提高,数值计算结果和实测结果吻合良好,从而证明了等效电路模型的准确性.%An equivalent circuit-genetic algorithm based modelling and optimal design approach was proposed to solve the problem of modeling and multi-objective optimal design for ultrasonic liquid level transducers. The equivalent circuit for an ultrasonic liquid level transducer was estab-lished by applying the electro-mechanical-acoustic analogy method, and the frequency response function and the output response function of the transducer were derived. In the multi-objective optimal design for the ultrasonic liquid level transducer, the dimensions of piezoelectric ceramics, the protection film thickness, and the gap between the transmitting probe and the receiving probe were chosen as the design variables! the peak-to-peak and the eigenvalue of output voltage were defined as the objective functions; two optimization tools, MATLAB and GA, were employed. The simulation results are in reasonable good agreement with the experimental data and the trans-ducer performance increases significantly. It seems that the equivalent circuit approach can pro-vide a useful tool for modeling ultrasonic liquid level transducers.