Method for improving measuring precision of thermal resistance thermometer

Abstract

The invention relates to and particularly discloses a method for improving measuring precision of a thermal resistance thermometer. The method comprises the following steps that 1, m points are selected within the measuring range of one thermal resistance thermometer as temperature correction datum points, and the output temperature value of the nth datum point is Yn; 2, the resistance value Rn of the nth temperature correction datum point is collected according to the data table of the thermal resistance thermometer; 3, an input temperature value Xn corresponding to the nth temperature correction datum point is acquired; 4, m-1 temperature intervals are formed by the m temperature correction datum points, and when a temperature value Ti measured by the thermal resistance thermometer is within the ith temperature interval, the gain Ai and polarization Bi of the ith temperature interval are obtained according to the step 3; 5, the temperature value Ti measured by the thermal resistance thermometer is calibrated and corrected, and a calibrated and corrected temperature value Ti' is obtained. According to the method, the measuring precision of the thermal resistance thermometer of a nuclear power plant is improved, the error of a whole temperature measuring channel is lowered, and the safety and economical efficiency of the power plant are improved.

Description

technical field [0001] The invention belongs to the field of nuclear power plant measurement, and in particular relates to a method for improving the measurement accuracy of thermal resistance thermometers in nuclear power plants. Background technique [0002] The temperature signal is a key monitoring parameter of the entire nuclear power plant. It plays an important role in the status monitoring and control of the process system and equipment. Many temperature signals are used for equipment shutdown and reactor protection shutdown. It is necessary for operators to operate safely and effectively. Information, accurate measurement of temperature signals is an important guarantee for the safe, reliable and economical operation of nuclear power plants. Therefore, it is very necessary to improve the measurement accuracy of the thermometer. [0003] At present, the RTD thermal resistance PT100 thermometer is widely used in domestic nuclear power plants, and its manufacturing ba...

AI Technical Summary

Problems solved by technology

[0005] With the wide application of digital technology, for example, domestic nuclear power plants such as Ling'ao Phase II, Hongyanhe, Ningde, Yangjiang, Fuqing, and Fangjiashan have adopted a fully digital DCS instrument and control platform, which is used to collect on-site temperature signals. The cards are all based on IEC60751, DIN or SAMA standards for resistance-temperature signal conversion. Although the acquisition card is hardware, it is impossible to reduce the deviation between the actual data of the thermometer and the standard by setting the card.

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