基于恒频交流电流法的微电阻精密测量系统

摘要

针对微电阻精密测量问题，设计了基于恒频交流电流法的微电阻精密测量系统，基于欧姆定律，根据被测电阻上的电压电流信号和噪声不相关的特性，把有用的信号提取出来，通过融合双相锁相放大原理和自适应滤波原理这两种检测技术，实现小电阻精密测量。详细介绍了系统三大主模块：主芯片数据处理模块、恒频交流电源模块、弱信号调理模块的软硬件设计。经过测试，该系统满足一般工程的实际应用要求，在电气测量的技术应用上有一定的参考价值和推广价值。%This paper introduced and implemented a low resistance precision measurement system based on the constant fre-quency AC current method and Ohm's Law.According to the non-correlation between the measured signal ( voltage and current through the low resistor) and noise,the useful signal can be extracted,and then we achieved low resistance precision measurement. The paper gave the details about software and hardware design of the system's three modules:CPU module,constant frequency AC source module and weak signal conditioning module.The experimental result verifies the correctness and reliability of the designed system.The system has a certain industrial and promotional value.