一种铂电阻测温电路的非线性校正方法

为克服铂电阻温度传感器的非线性带来的误差,在对铂电阻的非线性特性研究的基础上,设计了以恒流源非平衡电桥为基础的测温电路来代替传统的测温电桥.同时,采用分段最小二乘法拟合反向分度函数,以减小铂电阻自身的非线性带来的测量误差.最后给出基于stm32f103vbt6微控制器测温系统的实验结果,结果表明,铂电阻的非线性误差在0.03%以内,测温误差在0.25℃,满足大多数场合需要.

Nonlinear rectification for the circuit of platinum resistor in temperature measurement

In order to overcome platinum resistance temperature sensor error caused by the nonlinear, the circuit of Platinum resistance temperature is designed based on research about nonlinear characteristics of platinum resistance. In circuit, Non-equilibrium Bridge is driven by constant current source. Use sub-least-squares method to fit reverse indexing function to reduce measurement error caused by platinum non-linear. At last, the paper gives the results of the experimental which is temperature measurement system based on stm32f103vbt6, The results show that Non-linear error of Platinum Resistance is less than 0.03%, and temperature error is less than 0.25oC, this can meet the needs of the majority of situations.