Test the method for calibration of standard flow based on the steam turbine performance of auxiliary flow measurement
Technical field
The present invention relates to a kind of steam turbine performance of measuring based on auxiliary flow and test the method for calibration of standard flow.
Background technology
In the steam turbine performance test, standard flow adopts feedwater flow or condensing water flow usually, and power plant's feedwater flow measurement mechanism all is in High Temperature High Pressure and measures state, and its accuracy is difficult to guarantee behind the long-play.Though condensing water flow measurement mechanism measuring condition is better relatively, calculated by condensing water flow in the process of feedwater flow, also be subjected to the influence of other measurement parameter.If the accuracy of standard flow can be carried out verification by a kind of extra method, then can significantly improve the accuracy of standard flow in the performance test.
This important parameter of standard flow generally lacks the verification means in the steam turbine performance test at present, guarantees its accuracy.Therefore definite a kind of steam turbine performance of measuring based on auxiliary flow is tested the method for calibration of standard flow, and is necessary.
Summary of the invention
The object of the present invention is to provide a kind of steam turbine performance of measuring based on auxiliary flow to test the method for calibration of standard flow, hydrophobic data on flows and other associated hot force parameter that it can be surveyed to the oxygen-eliminating device pipeline according to well heater, calculate corresponding feedwater flow and condensing water flow, means and the method for verification finally can be provided the standard flow of steam turbine performance test.
The present invention solves its technical matters and adopts following technical scheme:
A kind of steam turbine performance of measuring based on auxiliary flow is tested the method for calibration of standard flow, and it comprises that step is as follows:
Step 1: to the hydrophobic pipeline of oxygen-eliminating device flow measuring sensor is installed at high-pressure heater, the installation of sensor should guarantee that its upstream and downstream have enough straight lengths; Utilize flow measuring sensor, the actual measurement high-pressure heater enters the hydrophobic flow W of oxygen-eliminating device
5d
Step 2: according to energy and the mass balance equation of oxygen-eliminating device and each high-pressure heater, adopt alternative manner to calculate corresponding to the hydrophobic flow W of actual measurement
5dFeedwater flow W
fAnd condensing water flow W
c
Step 3: the feedwater flow W that relatively calculates
fAnd measured performance test benchmark feedwater flow W
FtIf there is bigger deviation, to measured performance test benchmark feedwater flow W
FtRevise;
Step 4: the condensing water flow W that relatively calculates
cAnd measured performance test benchmark condensing water flow W
CtIf there is bigger deviation, to measured performance test benchmark condensing water flow W
CtRevise.
As a further improvement on the present invention, described step 2 is calculated by following formula:
Wherein:
W
f---feedwater flow, the t/h of unit;
W
8---No. eight high-pressure heater admission flows, the t/h of unit;
W
7---No. seven high-pressure heater admission flows, the t/h of unit;
W
6---No. six high-pressure heater admission flows, the t/h of unit;
W
5---oxygen-eliminating device admission flow, the t/h of unit;
W
5d---high-pressure heater is to the hydrophobic flow of oxygen-eliminating device, the t/h of unit;
W
Dout---oxygen-eliminating device water flow, the t/h of unit;
W
Level---the equivalent flow that deaerator level changes, the t/h of unit; Water level when rising be on the occasion of, be negative value during water level decline;
W
Ss---superheater desuperheating water flow, the t/h of unit;
W
Rs---reheater desuperheating water flow, the t/h of unit;
W
Si---Sealing Water for Feedwater Pump flow of inlet water, the t/h of unit;
W
So---Sealing Water for Feedwater Pump water flow, the t/h of unit;
W
c---oxygen-eliminating device incoming condensing water flow, the t/h of unit;
h
Fo8---No. eight high-pressure heater outlet Enthalpy of Feed Water, the kJ/kg of unit;
h
Fo7---No. seven high-pressure heater outlet Enthalpy of Feed Water, the kJ/kg of unit;
h
Fo6---No. six high-pressure heater outlet Enthalpy of Feed Water, the kJ/kg of unit;
h
Fo5---oxygen-eliminating device outlet Enthalpy of Feed Water, the kJ/kg of unit;
h
Fi8---No. eight high-pressure heater import Enthalpy of Feed Water, the kJ/kg of unit;
h
Fi7---No. seven high-pressure heater import Enthalpy of Feed Water, the kJ/kg of unit;
h
Fi6---No. six high-pressure heater import Enthalpy of Feed Water, the kJ/kg of unit;
h
Fi5---oxygen-eliminating device incoming condensing water enthalpy, the kJ/kg of unit;
h
8---No. eight high-pressure heater inlet steam enthalpies, the kJ/kg of unit;
h
7---No. seven high-pressure heater inlet steam enthalpies, the kJ/kg of unit;
h
6---No. six high-pressure heater inlet steam enthalpies, the kJ/kg of unit;
h
5---oxygen-eliminating device inlet steam enthalpy, the kJ/kg of unit;
h
8d---No. eight hydrophobic enthalpies of high-pressure heater, the kJ/kg of unit;
h
7d---No. seven hydrophobic enthalpies of high-pressure heater, the kJ/kg of unit;
h
6d---No. six hydrophobic enthalpies of high-pressure heater, the kJ/kg of unit.
The good effect of invention is as follows: the hydrophobic data on flows and other associated hot force parameter that adopt the inventive method to survey to the oxygen-eliminating device pipeline according to well heater, finally calculate corresponding feedwater flow and condensing water flow, means and the method for verification finally can be provided the standard flow of steam turbine performance test.
Solve the check problem based on standard flow in the steam turbine performance test, can provide foundation for the standard flow of accurately determining the steam turbine performance test, for the calculating of power plant's performance driving economy index provides accurate data, and be the energy-saving and cost-reducing foundation that provides of power plant.Standard flow to the power plant steam turbine performance test carries out continuous or periodic verification, guarantees the accuracy of its measurement.
Description of drawings
Accompanying drawing 1 is the hydrophobic flow sensor arrangenent diagram of the present invention.
Accompanying drawing 2 is for the present invention relates to the synoptic diagram of oxygen-eliminating device and high-pressure heater system.
In the accompanying drawing: 1, high-pressure heater 2, oxygen-eliminating device 3, hydrophobic flow sensor 4, hydrophobic operation valve 5, No. six high-pressure heaters 6, No. seven high-pressure heaters 7, No. eight high-pressure heaters.
Embodiment
At first on-the-spot high-pressure heater 1 is arranged to the hydrophobic pipeline of oxygen-eliminating device 2 and carried out suitable change, increase hydrophobic flow sensor 3.Hydrophobic flow sensor 3 is installed in before the hydrophobic operation valve 4, and the flow development length Lu before the hydrophobic flow sensor 3 are no less than 25 times of pipe diameter length, and hydrophobic flow sensor 3 backs are not less than 10 times of calibers to hydrophobic operation valves distance, and namely L is no less than 35 times of calibers.Can be referring to accompanying drawing 1.
Computing method and the step of standard flow are as follows:
Typical oxygen-eliminating device and high-pressure heater system as shown in Figure 2.There are following quality and energy-balance equation.
To No. eight high-pressure heaters 7, exist:
Wherein:
W
f---feedwater flow, the t/h of unit;
W
8---No. eight high-pressure heater admission flows, the t/h of unit;
h
Fo8---No. eight high-pressure heater outlet Enthalpy of Feed Water, the kJ/kg of unit;
h
Fi8---No. eight high-pressure heater import Enthalpy of Feed Water, the kJ/kg of unit;
h
8---No. eight high-pressure heater inlet steam enthalpies, the kJ/kg of unit;
h
8d---No. eight hydrophobic enthalpies of high-pressure heater, the kJ/kg of unit.
To No. seven high-pressure heaters 6, exist:
(2)
Wherein:
W
7---No. seven high-pressure heater admission flows, the t/h of unit;
h
Fo7---No. seven high-pressure heater outlet Enthalpy of Feed Water, the kJ/kg of unit;
h
Fi7---No. seven high-pressure heater import Enthalpy of Feed Water, the kJ/kg of unit;
h
7---No. seven high-pressure heater inlet steam enthalpies, the kJ/kg of unit;
h
7d---No. seven hydrophobic enthalpies of high-pressure heater, the kJ/kg of unit.
To No. six high-pressure heaters 5, exist:
Wherein:
W
6---No. six high-pressure heater admission flows, the t/h of unit;
h
Fo6---No. six high-pressure heater outlet Enthalpy of Feed Water, the kJ/kg of unit;
h
Fi6---No. six high-pressure heater import Enthalpy of Feed Water, the kJ/kg of unit;
h
6---No. six high-pressure heater inlet steam enthalpies, the kJ/kg of unit;
h
6d---No. six hydrophobic enthalpies of high-pressure heater, the kJ/kg of unit.
Wherein:
W
5d---high-pressure heater is to the hydrophobic flow of oxygen-eliminating device, the t/h of unit.
To oxygen-eliminating device 2, exist:
Wherein:
W
5---oxygen-eliminating device admission flow, the t/h of unit;
W
Dout---oxygen-eliminating device water flow, the t/h of unit;
W
Dlevel---the equivalent flow that deaerator level changes, the t/h of unit; Water level when rising be on the occasion of, be negative value during water level decline;
W
Ss---superheater desuperheating water flow, the t/h of unit;
W
Rs---reheater desuperheating water flow, the t/h of unit;
W
Si---Sealing Water for Feedwater Pump flow of inlet water, the t/h of unit;
W
So---Sealing Water for Feedwater Pump water flow, the t/h of unit;
h
Fo5---oxygen-eliminating device outlet Enthalpy of Feed Water, the kJ/kg of unit;
h
Fi5---oxygen-eliminating device incoming condensing water enthalpy, the kJ/kg of unit;
h
5---oxygen-eliminating device inlet steam enthalpy, the kJ/kg of unit.
To condensing water flow, mass balance exists:
(7)
Wherein:
W
c---oxygen-eliminating device incoming condensing water flow, the t/h of unit.
Calculation procedure is as follows:
Step 1: suppose a feedwater flow, according to other known thermal parameter, find the solution W by formula (1) respectively
8Find the solution W by formula (2)
7Find the solution W by formula (3)
6Find the solution W by formula (4)
5d
Step 2: the value W that relatively calculates
5dHydrophobic flow value W with actual measurement
5dtIn allowed band, then Jia Ding feedwater flow is the calculated value of feedwater flow as both errors; If error is bigger, then suppose feedwater flow again, go on foot from (1) and recomputate;
Step 3: according to the feedwater flow calculating value of determining, according to other known thermal parameter, find the solution W by formula (5) and formula (6)
5Find the solution condensing water flow W by formula (7)
c
The verification of standard flow is carried out as follows:
(1) the feedwater flow W that relatively calculates
fAnd measured performance test benchmark feedwater flow W
FtIf there is bigger deviation, to measured performance test benchmark feedwater flow W
FtRevise;
(2) the condensing water flow W that relatively calculates
cAnd measured performance test benchmark condensing water flow W
CtIf there is bigger deviation, to measured performance test benchmark condensing water flow W
CtRevise.
Embodiment 1:
Certain 600MW unit, measured data is as shown in the table, and the symbol implication is the same in the table:
Symbol |
Unit |
Numerical value |
W
5d |
t/h |
305.521 |
W
level |
t/h |
-0.366 |
W
ss |
t/h |
78.303 |
W
rs |
t/h |
6.338 |
W
si |
t/h |
4.500 |
W
so |
t/h |
4.500 |
h
fo8 |
kJ/kg |
1216.304 |
h
fo7 |
kJ/kg |
1092.593 |
h
fo6 |
kJ/kg |
942.794 |
h
fo5 |
kJ/kg |
791.557 |
h
fi8 |
kJ/kg |
1092.593 |
h
fi7 |
kJ/kg |
942.794 |
h
fi6 |
kJ/kg |
831.159 |
h
fi5 |
kJ/kg |
604.018 |
h
8 |
kJ/kg |
2999.451 |
h
7 |
kJ/kg |
2930.802 |
h
6 |
kJ/kg |
3406.405 |
h
5 |
kJ/kg |
3232.877 |
h
8d |
kJ/kg |
1112.492 |
h
7d |
kJ/kg |
954.210 |
h
6d |
kJ/kg |
861.701 |
Suppose different feedwater flow values, calculate according to abovementioned steps, until calculating W
5d, compare with measured value in the above-mentioned table; Repeat to revise the feedwater flow value, until the W that calculates
5dCoincide with the measured value in the above-mentioned table.Each flow rate calculation value that obtain this moment is as follows:
Symbol |
Unit |
Final calculated value |
W
f |
t/h |
1745.643 |
W
8 |
t/h |
114.446 |
W
7 |
t/h |
123.131 |
W
6 |
t/h |
67.944 |
W
5 |
t/h |
100.596 |
W
dout |
t/h |
1830.284 |
W
c |
t/h |
1424.533 |
The performance test benchmark feedwater flow W of field measurement
FtValue is 1762.4t/h, therefore the performance test benchmark feedwater flow W of actual measurement
FtCorrection be: 1745.64-1762.4=-16.76t/h;
The performance test benchmark condensing water flow W of field measurement
CtValue is 1432.36t/h, therefore the performance test benchmark feedwater flow W of actual measurement
FtCorrection be: 1424.533-1432.36=-7.83t/h.
Above embodiment is only unrestricted in order to technical scheme of the present invention to be described, although with reference to preferred embodiment the present invention is had been described in detail, those of ordinary skill in the art is to be understood that, can make amendment or be equal to replacement technical scheme of the present invention, and not breaking away from the spirit and scope of technical solution of the present invention, it all should be encompassed in the middle of the claim scope of the present invention.