一种基于PSD的转速测量新方法

转速测量方法如机械转速测量法、霍尔效应法等,其测量速度与动态测量范围有限。基于线阵CCD图像传感器实现的转速测量方法实时性受限,并易受振动、器件倾斜、亮条纹宽度等因素的影响。为了解决这些问题,提出了一种基于一维位置敏感器(position sensitive detector,PSD)的新型转速传感器。通过被测轴上的反射材料,将转轴的转速转变成光斑在PSD上的位置移动,利用PSD高速、高分辨率的特点,结合数字化的采集方案,实现了高、低大范围、非接触、高精度、实时性的转速测量,测量的最大转速达105r/s;当转速发生变化时,测量的波形能够在一个周期内进行调整,实时性可靠性高;实验在0~50 000 r/min内平均相对误差为0.079 1%,最大误差为0.168%,线性度优于1.1%,满足高精度测量的要求。

New method of speed measurement based on PSD

The speed measurement method has mechanical speed measuring method,Hall Effect method,etc.,its measuring speed and dynamic measuring range is limited.The speed measurement method based on linear CCD image sensor,which is limited in its real-time measurement,is easily influenced by vibration,tilting and light stripe width.In order to solve these problems,this paper proposes a novel speed sensor based on one dimensional position sensitive device （PSD）.By using the high resolution and high response speed of PSD and combined with STM32 chip with high processing speed the reflecting material on the shaft of being measured transfers the rotational signal into a mobile signal on PSD.A wide range of speed measurement of non-contact,high precision,real-time from high speed to low speed is attainable.It is able to measure the biggest transfer of 105 r/s.When speed changes,the measurement waveform is able to adjust in a cycle,its reliability and real-time are very high.In the experiment between the speed of 0 r/min and 50 000 r/min the average relative error of the new type of speed sensors is 0.0791％,maximum error is 0.168％,linearity is better than 1.1％,which meets the requirements of measurement.