CN103852183B - A kind of method improving thermal resistance thermometer certainty of measurement - Google Patents

Abstract

The present invention relates to, specifically disclose a kind of method improving thermal resistance thermometer certainty of measurement, comprise the following steps: 1 chooses m point as temperature correction datum mark within the scope of the measurement of a thermal resistance thermometer, and wherein the output temperature value of the n-th datum mark is Y_n；2 gather the resistance value R of the n-th temperature correction datum mark according to the tables of data of this thermal resistance thermometer_n；3 obtain the input temperature values X that the n-th temperature correction datum mark is corresponding_n；Described in 4, m temperature correction datum mark constitutes m-1 temperature range section, as the temperature value T that thermal resistance thermometer is measured_iGain A when being in i-th temperature range section, according to the i-th temperature range section that step 3 obtains_iWith biasing B_i；The temperature value T that 5 pairs of thermal resistance thermometers are measured_iIt is calibrated revising, is calibrated correction temperature value T_i'.The present invention improves the certainty of measurement of nuclear power plant's thermal resistance thermometer；Reduce the error of whole temperature measuring channel, improve safety and the economy of power plant.

Description

A kind of method improving thermal resistance thermometer certainty of measurement

Technical field

The invention belongs to nuclear power station fields of measurement, be specifically related to a kind of method improving nuclear power plant's thermal resistance thermometer certainty of measurement.

Background technology

Temperature signal is the key monitoring parameter of whole nuclear power plant; status monitoring for process system and equipment has important effect with control; a lot of temperature signals are for the protection shutdown of equipment protection stoppage in transit or even reactor; being the necessary information of operator's safety significant operations, the accurately measurement of temperature signal is the important guarantee of the safe and reliable of nuclear power plant and economical operation.Therefore the certainty of measurement improving thermometer is very important.

The extensive use of current RTD thermal resistance PT100 thermometer domestic nuclear power plant, it manufactures foundation for standard IEC 60751, due to the precision of thermometer itself, often there is certain difference between its real data and standard.And the assembly of collecting temperature signal or the conversion of its signal of fastener are according to all in accordance with IEC standard or other equivalence margins in power plant; thus the difference between resulting in the data and the thermometer real data that participate in subsequent arithmetic in real time is transmitted or strengthens further; although the precision of thermometer meets the requirement of manufacturer's standard, but for much participating in this difference of temperature signal controlled with protection the criterion calls being unsatisfactory for nuclear power plant.

Owing to traditional nuclear power plant is all based on analogue technique design, assembly for collection site temperature signal is all the conversion completing signal according to ICE60751 standard, the process of follow-up signal also all completes within hardware, but due to the binding character of hardware, generally it is difficult to from source by arranging the certainty of measurement improving thermometer and reducing the difference between manufaturing data and the standard that thermometer is actual.Thus the control pressure of passage precision is all added on the assembly such as subsequent mathematical, logical operations.

Extensive use along with digitizing technique, such as domestic ridge Australia is the second stage of, red along the river, Ningde, Yangjiang, Fuqing, Fan family Shan Deng nuclear power plant just have employed the DCS instrument control platform of total digitalization, it is all the conversion carrying out resistance temperature signal according to IEC60751, DIN or SAMA standard for the fastener of collection site temperature signal, although this collection fastener is hardware, it is impossible to by fastener arranged the deviation reduced between thermometer real data and standard.

Summary of the invention

It is an object of the invention to provide a kind of temperature utilizing thermal resistance thermometer to gather fiducial temperature point, by the method for calibration calculations and then raising nuclear power plant thermal resistance thermometer certainty of measurement.

Realize technical scheme as follows: comprise the following steps:

Step one, choose within the scope of the measurement of a thermal resistance thermometer m point as temperature correction datum mark, wherein the output temperature value of the n-th datum mark is Y_n, n=1,2,3 ..., m；

Step 2, tables of data according to this thermal resistance thermometer gather the resistance value R of the n-th temperature correction datum mark_n；

Step 3, the n-th temperature correction datum mark collected according to step 2 resistance value R_n, and then obtain, by following formula, the input temperature values X that the n-th temperature correction datum mark is corresponding_n；

R_n=R₀(1+AX_n+BX_n ²)；

Step 4, described m temperature correction datum mark constitute m-1 temperature range section, as the temperature value T that thermal resistance thermometer is measured_iGain A when being in i-th temperature range section, according to the i-th temperature range section that step 3 obtains_iWith biasing B_i；

Wherein, i=1,2,3 ..., m-1； $A_i=\frac{Y_{i+1}-Y_i}{X_{i+1}-X_i};$ $B_i=-\frac{Y_{i+1}-Y_i}{X_{i+1}-X_i}{X}_{i+1}+Y_{i+1};$

Step 5, the temperature value T that thermal resistance thermometer is measured_iIt is calibrated revising, is calibrated correction temperature value T '_i；

T‘_i=A_iT_i+B_i。

In described step 3, R₀=100 Ω, when according to IEC6075 standard, A=3.9083 × 10^-3°C^-1, B=-5.775 × 10^-7°C^-2；When according to DIN43760-1980 standard, A=3.90802 × 10^-3℃^-1, B=--5.80201 × 10^-7°C^-2；

Having the beneficial effect that acquired by the present invention:

(1) certainty of measurement of nuclear power plant's thermal resistance thermometer is improved；

(2) reduce the error of whole temperature measuring channel, improve safety and the economy of power plant.

Detailed description of the invention

A kind of method improving thermal resistance thermometer certainty of measurement of the present invention, comprises the following steps:

Step one, choose within the scope of the measurement of a thermal resistance thermometer m point as temperature correction datum mark, wherein the output temperature value of the n-th datum mark is Y_n, n=1,2,3 ..., m；

Step 2, each thermal resistance thermometer all with tables of data, gather the resistance value R of the n-th temperature correction datum mark when dispatching from the factory according to the tables of data of this thermal resistance thermometer_n；

Step 3, the n-th temperature correction datum mark collected according to step 2 resistance value R_n, and then obtain, by following formula, the input temperature values X that the n-th temperature correction datum mark is corresponding_n；

R_n=R₀(1+AX_n+BX_n ²)；

Wherein, R₀=100 Ω, when according to IEC6075 standard, A=3.9083 × 10^-3℃^-1, B=-5.775 × 10^-7°C^-2；When according to DIN43760-1980 standard, A=3.90802 × 10^-3°C^-1, B=--5.80201 × 10^-7°C^-2；

Step 4, described m temperature correction datum mark constitute m-1 temperature range section, as the temperature value T that thermal resistance thermometer is measured_iGain A when being in i-th temperature range section, according to the i-th temperature range section that step 3 obtains_iWith biasing B_i；

Wherein, i=1,2,3 ..., m-1； $A_i=\frac{Y_{i+1}-Y_i}{X_{i+1}-X_i};$ $B_i=-\frac{Y_{i+1}-Y_i}{X_{i+1}-X_i}{X}_{i+1}+Y_{i+1};$

Step 5, the temperature value T that thermal resistance thermometer is measured_iIt is calibrated revising, is calibrated correction temperature value T '_i；

T‘_i=A_iT_i+B_i。

Instantiation is as follows:

1、m=8

Temperature correction datum mark Y is chosen within the scope of RTD thermometer measure₁..., Y₈And gather each temperature correction datum mark correspondence resistance value, as follows:

Y1

Y2

Y3

Y4

Y5

Y6

Y7

Y8

0℃

60℃

120℃

180℃

240℃

290℃

350℃

400℃

100.049Ω

123.314Ω

146.153Ω

168.567Ω

190.555Ω

208.554Ω

229.763Ω

247.112Ω

2, the X that each temperature correction datum mark is corresponding is obtained₁..., X₈, as follows:

X1

X2

X3

X4

X5

X6

X7

X8

0.0553℃

60.1889℃

120.2265℃

180.2408℃

240.2274℃

290.1972℃

350.1349℃

400.0591℃

3, the gain A of each temperature range section is determined_iWith biasing B_i, final calibration correction is as follows:

4, calibration correction temperature broken line graph is drawn according to the broken line gain calculated with biasing.

5, the temperature value T measured according to thermal resistance thermometer_i, it is calibrated correction temperature value T '_i, as shown in the table:

Claims (2)

1. the method improving thermal resistance thermometer certainty of measurement, it is characterised in that: comprise the following steps:

Step one, choose within the scope of the measurement of a thermal resistance thermometer m point as temperature correction datum mark, wherein the output temperature value of the n-th datum mark is Y_n, n=1,2,3 ..., m；

Step 2, tables of data according to this thermal resistance thermometer gather the resistance value R of the n-th temperature correction datum mark_n；

Step 3, the n-th temperature correction datum mark collected according to step 2 resistance value R_n, and then obtain, by following formula, the input temperature values X that the n-th temperature correction datum mark is corresponding_n；

$R_n=R_0(1+{\mathrm{AX}}_n+{\mathrm{BX}}_n^2);$

Step 4, described m temperature correction datum mark constitute m-1 temperature range section, as the temperature value T that thermal resistance thermometer is measured_iGain A when being in i-th temperature range section, according to the i-th temperature range section that step 3 obtains_iWith biasing B_i；

Wherein, i=1,2,3 ..., m-1； $A_i=\frac{Y_{i+1}-Y_i}{X_{i+1}-X_i};B_i=\frac{Y_{i+1}-Y_i}{X_{i+1}-X_i}{X}_{i+1}+Y_{i+1};$

Step 5, the temperature value T that thermal resistance thermometer is measured_iIt is calibrated revising, is calibrated correction temperature value T_i'；

T_i'=A_iT_i+B_i。

2. the method improving thermal resistance thermometer certainty of measurement as claimed in claim 1, it is characterised in that: in described step 3, R₀=100 Ω, when according to IEC6075 standard, A=3.9083 × 10^-3℃^-1, B=-5.775 × 10^-7℃^-2；When according to DIN43760-1980 standard, A=3.90802 × 10^-3℃^-1, B=-5.80201 × 10^-7℃^-2。