Dynamic calibration method of temperature sensor based on Quasi‐δ pulse temperature excitation

Abstract

AbstractAiming at the existing problems in the dynamic calibration method of temperature sensor, Quasi‐δ pulse temperature dynamic calibration method is proposed. The Quasi‐δ pulse dynamic calibration principle was described, the characteristics of Quasi‐δ pulse function were analyzed, and the relationship among pulse width of Quasi‐δ signal, frequency range that can be calibrated, and calibration precision was obtained. Quasi‐δ pulse temperature dynamic calibration system was built using the laser as the heat source which generates the excitation temperature required for dynamic calibration. In the system, optical focusing system was designed using ellipsoidal mirror which has a better conjugate imaging property. Applying the dynamic calibration system, a K‐type armored thermocouple was calibrated dynamically, and mathematical model of the calibrated thermocouple was established by generalized least squares method based on a special whitening filter. Dynamic characteristics of the thermocouple in time domain and frequency domain were analyzed.