热电阻的动态响应特性

热电阻是最普遍使用的测温元件之一,工程中一般给出热电阻测量的滞后时间,而对测量的过渡过程缺乏深入的分析。以WZP1500型、WZP120型和有导热油的WZP120型Pt100热电阻为例,研究了它们的过渡过程。通过对实验数据的分析综合、参数辨识,得到了它们的阶跃时间响应函数和传递函数。同时,对影响热电阻数学模型结构的因素、影响数学模型参数大小的因素进行了分析,得到的结论可用于新热电阻数学模型的建立。

Dynamic Response Characteristic of Thermal Resistances

Thermal resistance (RTD) is one of the sensors of temperature measurement most widely used now. In engineering,the lag time of temperature measurement is provided by manufacturers commonly, but the transient process of temperature measurement is short of systematical study. Taking Pt100 thermal resistance, type WZP1500, type WZP120 and WZP120 soaked in heat conducting oil, as examples, the transient processes are investigated thoroughly. Through carrying out analysis and synthesis on the experiment data and identification of parameters of math models, their responses against step input and its transfer functions are obtained. Meanwhile, further investigation on the factors which have influence on the structure of math models of thermal resistances and on the factors which have influence on the size of parameters in the math models of thermal resistances are carried out. The reached conclusions can be used in an establishment of math model of new thermal resistance.