时栅角位移传感器中的多普勒效应影响及其抑制方法研究

Study on the influence of Doppler effect and its suppressing method in time grating angular displacement sensor

为了适应更多应用场合,时栅角位移传感器需具备动态测量能力,即在传感器动测头转动时进行测量,但传感器的动测头相对于旋转磁场的速度会影响其输出信号的频率和幅值,该现象是一种特殊的多普勒效应。由于动测头信号频率发生变化,所以电路的相频特性和幅频特性使动态测量精度下降。从理论和实验两方面详细分析了这种多普勒效应及其对时栅传感器的影响,并介绍了对该多普勒效应影响的抑制方法。其中,提高旋转磁场速度的方法通过实验验证使动态测量误差减小达90%。

In order to fit more applications,time grating angular displacement sensor needs to have the ability of dynamic measurement,i.e.taking measurement when the moving sensor-head is rotating.The speed of the moving sensor-head relative to rotating magnetic field in time grating sensor has an effect on the frequency and amplitude of its output signal,this phenomena is a special kind of Doppler effect.The phase-and amplitude-frequency characteristics of the circuit decrease the dynamic measurement accuracy because the frequency of moving sensor-head output signal changes.The special Doppler effect and its influence on time grating sensor are analyzed in detail from both theoretical and experimental aspects,followed by introducing the methods to reduce the influence,within which the method of increasing magnetic field rotating speed is verified in actual experiment,it can decrease the dynamic measurement error by 90％.