磁致伸缩位移传感器反射波电压特性与阻尼参数优化

为了提高磁致伸缩位移传感器的稳定性和测量准确性,降低反射波信号对输出电压有效信号的影响,对反射波电压产生原因及影响因素进行了研究。从阻尼与波导丝之间的弹性压力及其产生的摩擦力对应力波传播影响的角度,构建了阻尼作用下磁致伸缩位移传感器反射波电压模型,计算了磁致伸缩位移传感器的反射波电压幅值,利用搭建的实验平台,通过实验获得不同阻尼参数作用下的反射波电压幅值变化。结果表明,计算结果与实验结果的变化趋势基本一致,阻尼对反射波电压幅值有很大影响。基于反射波电压模型,确定了阻尼长度和邵氏硬度最佳取值范围分别为5~10mm、50~75,在直径为10mm、长度为10mm和邵氏硬度为50的最优阻尼作用下,反射波电压幅值从75mV降低至4mV,此时反射波电压幅值远小于有效信号,从而大大降低了对输出电压有效信号造成的影响。本研究可为磁致伸缩位移传感器阻尼选择提供理论依据。

Voltage Characteristics of Reflected Wave of Magnetostrictive Displacement Sensor and Damping Parameter Selection

In order to improve the stability and measurement accuracy of the magnetostrictive displacement sensor, and reduce the influence of the reflected wave signal on the effective signal of the output voltage, the generation and influence factors of the reflected wave voltage were studied. Based on the analysis of the influence of elastic pressure between damping and waveguide wire and the friction generated on the stress wave propagation, a voltage model of the reflected wave of the magnetostrictive displacement sensor under the action of damping was constructed, and the voltage amplitude of the reflected wave of the magnetostrictive displacement sensor was calculated. The results showed that the change of the damping parameter had a great influence on the amplitude of the reflected wave voltage, and the calculation result was basically consistent with the change trend of the experimental result. Based on the reflected wave voltage model, the optimal values of the damping length and Shore hardness were determined to be 5~10mm and 50~75, respectively, and the damping with a diameter of 10mm, a length of 10mm and a Shore hardness of 50 experimental verification were verified by experiments. Under the damping effect, the amplitude of the reflected wave voltage was reduced from 75mV to 4mV. At this time, the amplitude of the reflected wave voltage was much smaller than that of the effective signal, which greatly reduced the impact on the effective signal of the output voltage. The research result can provide a theoretical basis for the selection of damping parameters of the magnetostrictive displacement sensor.