基于d-q变换的时栅位移传感器补偿算法研究

时栅位移传感器是一种新型的栅式位移传感器,它不依赖于空间等分性,通过对时间脉冲进行计数而间接实现位移测量,从而达到高精度测量。介绍了传感器信号变形的原因,将非理想信号分为幅度不均、相位偏移、谐波叠加、波形变形四大类;针对幅度不均的情况,将电机学中的d-q变换引入误差分析,推导出其对寄生式时栅位移传感的误差影响;同时在d-q变换原理的视角下重新审视了时栅传感器的测量过程。提出了一种基于变换空间下的误差补偿算法,d轴的差分项与q轴误差项变化趋势一致,利用变化规律对测量误差进行实时修正。在安装有寄生式时栅位移传感器的实验台上进行了实验并获取到不同情况下的误差曲线,实验结果表明,该补偿算法可以消除幅度不均带来的二次误差,误差压制量达到90%。这种算法完全利用信号本身的特性,无需复杂的运算,将误差部分进行了补偿达到了比较理想的效果,对于寄生式时栅位移传感器的实际应用具有重要意义。

Research on compensation algorithm of time grating sensor using d-q transformation

Time grating sensor is a novel sensor and it can achieve very high accuracy owing to a special way that measure time using pulse with high frequency. In this paper, the reasons of signal distortion have been introduced firstly, including the imbalance of amplitude, imperfect quadrature, inductive of harmonics. In particular, aim to the angular deviation from the imbalance of amplitude, the letter introduces the d q transform from electrical machinery to solve it and deduces the angular deviation. The process of measuring is analyzed using rotating coordinate system where an error compensation algorithm has been proposed. The error would be corrected with a simply way due to the fact that the algorithm utilizes the characteristic of signal completely. Finally, the proposed method was applied to the experimental system and the error of sensor was obtained under different circumstances. Experimental results indicate the curve of error consist of 2th harmonic because of the imbalance of amplitude. The deviation of angular information from the imbalance of amplitude will be eliminated if the algorithm is applied .it will get good result with the algorithm and it will be make sense for time grating sensor.