基于铂电阻的温度高精度测量研究

针对采用铂电阻对温度进行高精度测量，从硬件电路和曲线拟合2个方面进行了研究。电路上采用同一个电压给传感器恒电流驱动电路和A／D转换电路作参考电压，保证了温度检测的精度，并用最小二乘法直接拟合了描述采样值一温度关系的曲线，弥补了Pt100测温时信号从铂电阻到A／D转换的过程中各个中间环节所产生的偏差。该方法可使测量偏差优于0．05℃，并已在研制的高精度温度温差控制系统中得到应用。

Study of high-precision temperature measurement based on platinum resistance

The high-precision measurement of temperature in platinum resistance is introduced,its research covers two aspects,such as the hardware circuit and curve fitting.In hardware circuits sensor constant current drive circuit and A/D converter circuit use the same voltage as a reference voltage,so it guarantees the temperature measurement accuracy.In curve fitting,it fits the curve which describes the relations of sampling value-temperature by using least squares method,It compensates the deviation which occurs in each middle part of the signal from platinum resistance to the A/D conversion in the temperature measurement of Pt100.This method can make measurement error superior to 0.05℃,and now it applies to the development of high-precision temperature thermal control system.