用于高精度光栅信号的零相移滤波器设计  

Design of zero phase shift filter applied to high-precision grating signal

作　　者：严刚峰[1,2,3] 唐勇 YAN Gangfeng;TANG Yong(Chengdu University,Chengdu 610106,China;Anhui Polytechnic University,Wuhu 214000,China;State Key Laboratory of Large Electric Transmission System and Equipment Technology,Tianshui 741020,China)

机构地区：[1]成都大学,四川成都610106 [2]安徽工程大学,安徽芜湖214000 [3]大型电气传动系统与装备技术国家重点实验室,甘肃天水741020

出　　处：《中国测试》2023年第10期135-139,147,共6页China Measurement & Test

基　　金：安徽省重点实验室开放研究基金资助项目(JCKJ2021B04);国家重点实验室开放基金课题(SKLLDJ022020003)。

摘　　要：为实现光栅的低成本、高精度测量,以栅距为20μm的光栅为研究对象,分别讨论光栅输出信号振幅、相位、直流漂移以及3次谐波存在时,与理想输出信号对比所导致测量误差的情况,发现光栅信号3次谐波、相位波动(非正交)引起的测量误差比较大。由此提出先采用零相移滤波器进行光栅信号处理,然后再细分测量的方法,并详细给出零相移滤波器的设计过程和参数选择方法。通过实测结果,比较测量精度为0.1μm的位移传感器的测量结果,光栅信号直接128倍细分的测量结果,以及零相移滤波后的光栅信号进行128倍细分的测量结果,其最大误差由0.0011 mm减少到0.0003 mm。在低成本的情况下,实现较高精度的光栅测量。In order to realize the low-cost and high-precision measurement of the grating,the grating with a grating pitch of 20μm is used as the research object,the measurement errors caused by the comparison with the ideal output signal when the grating output signal amplitude,phase,DC drift and the existence of the 3rd harmonic are discussed respectively.It is found that the measurement error caused by the 3rd harmonic of the grating signal and the phase fluctuation(non-orthogonal)is relatively large.Therefore,a method of first using zero-phase-shift filter to process grating signal,and then subdividing measurement is proposed,and the design process and parameter selection method of zero-phase-shift filter are given in detail.Through the actual measurement results,the measurement results of the displacement sensor with a measurement accuracy of 0.1μm,the measurement results of the grating signal directly subdivided by 128 times,and the measurement results of 128 times subdivision of the grating signal after zero phase shift filtering are compared.The maximum error is reduced from 0.0011 mm to 0.0003 mm.It achieves high-precision grating measurement at low cost.

关 键 词：光栅信号 细分 零相移滤波 分辨率 

分 类 号：TB921[一般工业技术—计量学]