高压非共地信号采集系统设计及误差标定分析

Design and Error Calibration Analysis of High‑Voltage Non‑Common Ground Signal Acquisition System

针对引信电路板拼板测试需求,设计了一种多通道高压非共地信号采集系统。建立了信号调理电路和模数转换电路的误差模型,提出了增益误差校准算法,解决了信号采集电路在小电压范围内相对误差过大的问题,保证了全电压范围内的采集精度。同时,提出了信号调理电路模块化标定技术,通过最小二乘法求出标定最优解,实现了对信号调理电路的软件校准,解决了因分压电阻阻值误差、运放失调电压产生的误差问题。经试验验证表明,数据采集系统能够精确复现多通道信号波形,全电压范围内的相对误差不超过1%,满足测试系统精度需求,大大简化了多通道调理电路标定步骤。

Aiming at the test requirements of fuze circuit board panels,a multi-channel high-voltage noncommon ground signal acquisition system is designed.The error model of the signal conditioning circuit and analogue-to-digital conversion circuit is established,and the gain error calibration algorithm is proposed,which solves the problem of excessive relative error of signal acquisition circuit in small voltage range and ensures the acquisition accuracy in the full voltage range.At the same time,the modular calibration technology of the signal conditioning circuit is proposed,and the optimal solution for calibration is obtained by the least squares method,which realizes the software calibration of the signal conditioning circuit,and solves the error problem caused by the resistance error of the voltage division resistor and the offset voltage of the op-amp.The experimental verification shows that the data acquisition system can accurately reproduce the multi-channel signal waveform,and the relative error in the full voltage range does not exceed 1%,which meets the accuracy requirements of the test system and greatly simplifies the calibration steps of the multi-channel conditioning circuit.