一种提高数据采集系统精度的方法

数据采集系统对采集精度要求极高,但采用12位的高精度模数转换器AD774BKN,直接利用标称值元器件设计的数据采集系统仍然存在系统误差.尽管使用传统的线性参数标度变换可以消除系统误差,但数据采集系统必须是线性系统.如果存在饱和非线性,最好在多种输入情况下分段处理测量的若干数据,饱和区采用传统的标度变换法,非饱和区应用最小二乘法拟合的线性关系进行标度变换得到测量值.实验结果证明该方法比传统的标度变换计算的测量值要明显准确,达到提高系统精度的良好效果.

Method for Increasing Accuracy of Data Acquisition System

Data acquisition system requires high accuracy. When the data acquisition system designed with 12-byte high resolution AD774BKN and directly used the nominal value components, it still existed system error. The traditional linear parameters scale transform method can eliminate system error, but it happens when the data acquisition is linear system. If there is a saturation of nonlinearity, it is better to measure several data in a variety of input cases and make segment handling. Using the traditional scale transformation to deal with the saturation data and using the linear relationship by the least squares fitting scale transform with non-saturation can get the measured values. The experimental results show that calculation measurements using this method are much better accurate than the traditional scale transformation. It can get good effect to improve the system accuracy.