超低频信号测量中ADC系统的设计与实现

Design and implementation of the ADC system for ultra-low-frequency signal measurement

本文分析了超低频交流信号的测量方法,设计了一种基于采样计算方式的ADC采集系统,设计了ADC采样电路及单端转差分驱动电路,分析了ADC量化误差对交流信号测量准确度的影响,提出了交流信号有效值测量准确度与ADC分辨率位数和采样点数的定量关系式。对所设计并实现的ADC采集系统进行了测试,测试数据经线性修正后的相对误差小于等于0.0011%,满足设计目标要求。

Analyzed the measuring methods of ultra-low-frequency AC signal,and designed an ADC acquisition system based on sampling-calculation.Designed the ADC sampling circuit,and designed the single-to-differential input driver circuit.Analyzed the impact of the AC signal measurement accuracy by the ADC quantization error,and proposed the quantitative relationship among the AC signal RMS measurement accuracy,the number of ADC bits,and the number of sampling points.Tested the ADC acquisition system,and the relative error of the test data by linear correction was less than or equal to 0.0011%which was met the project requirements.