Series structure-based resistance thermometry readouts offer several advantages for multi-point temperature measurements. However, because of the diversity of nonlinear error sources and differences among channels in such readouts, existing nonlinear error correction methods are ineffective. In view of this situation, a nonlinear error correction method based on error source analysis is proposed. The proposed method first determines the impacts of error sources by analyzing the circuit architecture. The contributions of the common-mode rejection ratio and the mismatch between positive and opposite exciting currents are then eliminated using resistance bridge calibrators. Finally, the residuals are fitted to various polynomial functions. The results of experiments show that correction based on the proposed method results in a maximum nonlinear readout error of 1.87 × 10-5, compared with 4.01 × 10-5 using the classical method. Thus, the proposed method of nonlinear error correction is effective for series structure-based resistance thermometry readout.

中文翻译：

---

校正基于串联结构的电阻测温读数中的非线性

基于串联结构的电阻测温读数为多点温度测量提供了多种优势。然而，由于这种读出中非线性误差源的多样性和通道之间的差异，现有的非线性误差校正方法是无效的。针对这种情况，提出了一种基于误差源分析的非线性误差校正方法。所提出的方法首先通过分析电路架构来确定误差源的影响。然后使用电阻桥校准器消除共模抑制比的影响以及正反向励磁电流之间的失配。最后，残差适合各种多项式函数。实验结果表明，基于所提出方法的校正导致最大非线性读数误差为 1.87 × 10-5，而使用经典方法的误差为 4.01 × 10-5。因此，所提出的非线性误差校正方法对于基于串联结构的电阻测温读数是有效的。