故障信号检测虚拟示波器数据采集系统设计

Design of data acquisition system for virtual oscilloscope to detect fault signal

为了获取虚拟示波器故障信号数据,设计一种故障信号检测虚拟示波器的数据采集系统,该系统主要由衰减保护控制电路、信号调理电路、A/D转换、数据缓存和单片机5部分组成。通过减少信号调理电路使输入信号和A/D模块满量程值之间的差异达到理想的精确度。利用单片机ATmega32和AD574组成的A/D转换电路对数据进行转换和采集。在系统的输入端设计比例衰减与过压保护电路,避免因电压幅值过大造成芯片损坏。软件设计中,详细分析A/D采集的主程序及相关实现代码。实验结果表明,所提系统采集精度高,所需时间短,具有很高的采集性能。

In order to acquire the fault signal data of virtual oscilloscope, a data acquisition system for virtual oscilloscope to detect fault signal was designed. The system is mainly composed of the attenuation protection and control circuit, signal conditioning circuit, A/D conversion, data cache and single chip microcomputer. The difference between the full scale value of A/D module and input signal is reduced through the signal conditioning circuit to make the D/A conversion achieve the desired accu- racy. The A/D conversion circuit composed of ATmega32 and AD574 is used to convert and acquire the data. The proportion damping and overvohage protection circuit are designed for input end of the system to avoid the chip damage caused by excessive voltage amplitude. In software design, the correlation implementation code and main program acquired by A/D are analyzed in detail. The experimental results show that the proposed system has high acquisition precision, short acquisition time, and high acquisition performance.