Study on Influence Factors of High Stability Temperature Control by AC Bridge in 5~25 K Deep-Low Temperature Region

Abstract: Temperature control stability is one of the key factors affecting the uncertainty of thermodynamic temperature measurement in deep low-temperature regions, the reliability of international comparison of thermodynamic temperatures, and the level of temperature calibration. In order to explore the influencing factors of high stability temperature control in deep low-temperature areas, based on previous research, a temperature control experimental plan for thermometer lead resistance and standard resistance was designed. Relevant temperature control experiments were conducted at 5K and 25K to quantitatively evaluate the disturbance effect of thermometer lead resistance and standard resistance on the average temperature measurement value and temperature control stability in deep low-temperature areas. The results show that the average temperature measurement value is almost unaffected by the lead resistance and standard resistance; The temperature control stability will vary with the lead resistance and standard resistance. The lower the lead resistance, the higher the temperature control stability in deep low-temperature areas, and there is an optimal matching standard resistance. The research results can provide reference for constructing a highly stable low-temperature working environment in deep low-temperature areas.