A dynamic calibration system of thermocouple sensor ased on high temperature furnace

摘要

In the field of dynamic temperature measurement, the dynamic characteristics of sensors are critical and should meet test requirements. Thermocouples are widely used for temperature measurement in the harsh conditions due to their low cost, robustness and reliability. But there is a dynamic error in the dynamic temperature measurement, because of the presence of the thermal inertia. So it is important to dynamically calibrate the thermocouples and understand their dynamic characteristics. In this paper, based on the analysis of step and ramp excitation signal, a variety of dynamic calibration methods of thermocouples were introduced. The dynamic calibration system of thermocouple sensor based on high temperature furnace was established, and the dynamic calibration experiment of a bare thermocouple was done. The time constant of the thermocouple was obtained, and its estimation error is less than 1%.