双电桥在精密温度测量系统中的应用研究

Application of double bridge circuit in precise temperature measurement system

针对传统单电桥测温精度已不满足精密温度测量系统需求的问题,在分析双电桥测量微小电阻值原理的基础上,从线性度、准确度和灵敏度角度考虑,通过研究改进,完成了基于四线制的双电桥精密温度测量电桥的设计,用于配合铂电阻Pt1000实现捷联航姿系统温控系统的精密温度测量;通过计算机仿真和工程试验对线性度、准确度和灵敏度进行了分析验证.计算机仿真和工程试验结果证明采用双电桥能有效地完成精密温度测量.

The measurement precision of traditional single bridge circuit cannot satisfy the demand of precise temperature measurement system. Based on the analysis of the principle of measuring tiny resistance with double bridge circuit, considering the linearity, accuracy and sensitivity of the circuit, this paper has achieved the design of a high precision temperature measurement circuit based on four-wire resistance-connection double bridge circuit, which is used to work with Pt1000 resistance to realize accurate temperature measurement for strap down attitude reference system. The computer simulation and project testing data show that this double bridge circuit can achieve high precision temperature measurement.