On-line calibration system for redundant temperature sensors

Abstract

Automated plant instrumentation system for cross calibration based on data stored by a plant computer and data storage unit or a plant monitoring system. The automated system includes a processor executing software for retrieving data, determining average temperatures, determining deviations, and determining new calibration curve coefficients for deviating instruments. In another embodiment, the processor executes software for loading the historical data, selecting data points, removing deviate data, analyzing the data, reporting the data, and for recalibrating instruments that were determined to be deviating.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] Not Applicable STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0002] Not Applicable BACKGROUND OF THE INVENTION [0003] 1. Field of Invention [0004] This invention pertains to methods and apparatus for performing RTD and thermocouple cross-calibration in nuclear power plants. More particularly, this invention pertains to using data acquired by a plant monitoring system to calibrate hot leg and cold leg temperature instrumentation in a pressurized water reactor. [0005] 2. Description of the Related Art [0006] Pressurized water reactors (PWRs) produce heat through a nuclear reaction in a reactor vessel. The heat is extracted from the reactor vessel by pumping water from the reactor vessel to one or more steam generators. The steam generator is a heat exchanger that extracts the heat from the reactor water into steam that drives a turbine. The piping carrying the heated water from the reactor vessel is called the hot leg, a...

AI Technical Summary

Benefits of technology

The automated system enhances data availability during calibration, reduces manual intervention, and minimizes downtime, enabling continuous monitoring and improving the efficiency of the calibration process.

Problems solved by technology

However, if the deviation exceeds the acceptance limits, the sensor is considered out of calibration and its use for plant operation must be evaluated.

These prior art methods have the disadvantage of removing the instruments from service for the period measurements are taken, resulting in less information being provided to the plant operators.

Additionally, the prior art methods require time and manpower to perform the cross calibrations.

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