CN105241667B - Condenser vacuum condition discrimination method based on k M models - Google Patents
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- 238000012850 discrimination method Methods 0.000 title claims abstract description 7
- 238000012546 transfer Methods 0.000 claims abstract description 43
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- 238000005259 measurement Methods 0.000 claims description 5
- 230000002159 abnormal effect Effects 0.000 claims description 4
- 238000011056 performance test Methods 0.000 claims description 2
- 238000012360 testing method Methods 0.000 abstract description 7
- 238000000034 method Methods 0.000 description 11
- 239000002826 coolant Substances 0.000 description 4
- 238000001816 cooling Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000013528 artificial neural network Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- YBMRDBCBODYGJE-UHFFFAOYSA-N germanium dioxide Chemical compound O=[Ge]=O YBMRDBCBODYGJE-UHFFFAOYSA-N 0.000 description 2
- 238000005457 optimization Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
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- 230000005611 electricity Effects 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000012417 linear regression Methods 0.000 description 1
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Abstract
The present invention relates to a kind of condenser vacuum condition discrimination method based on k M models, based on limited experimentation data, the normal heat transfer coefficient of condenser is set upk c And dimensionless groupMBetween functional relation, and then determine any operating condition of unit under condenser normal heat transfer coefficientk c , by the deviation of relatively normal heat transfer coefficient and actual heat transfer coefficient, judge whether condenser condenser vacuum is normal.Compared with prior art, the present invention is not necessary to know the specific physical dimension of condenser, is determined whether the vacuum of condenser under any stable operating mode is normal using the test data of limited stability operating mode for given actual set.
Description
Technical field
It is more particularly to a kind of solidifying based on k-M models the present invention relates to a kind of condensing steam turbine generator group diagnostic techniques
Vapour device vacuum state method of discrimination.
Background technology
Condenser and its accessory system are Turbo-generator Set cold ends, and operation of its running status to Turbo-generator Set has
It is significant, therefore research on condenser operational diagnostics and optimization is constantly subjected to extensive attention with application.Condenser
Operational diagnostics and the premise of optimization are to judge whether condenser vacuum is normal.Judge all be when whether condenser vacuum state is reasonable
By the way that actual measurement condenser pressure and condenser pressure should be compared to up to value to judge.Condenser pressure should be up to the determination one being worth
As have two class methods.
(1) conventional method:
With condenser pressure PcCorresponding saturated-steam temperature tsIt can be determined by formula (1):
ts=tw1+Δt+δt (1)
T in formulaw1For cooling water inlet temperature, Δ t is cooling water temperature rise, and δ t are condenser terminal difference.
When ignoring into other heats of condenser, the condensation heat amount of steam is equal to the caloric receptivity of cooling water, then cold
But the temperature rise of water can be calculated by (2) formula:
C in formulapFor the specific heat capacity of water, DwFor cooling water flow, DcFor turbine discharge amount, hcFor exhaust enthalpy of turbine, hc′
For condensate enthalpy.
Condenser terminal difference can be calculated by (3) formula:
A is condenser effective heat transfer area in formula, and k is condenser heat transfer coefficient.In traditional determination method, in engineering
Condenser heat transfer coefficient determines that what application was wider at present is that U.S.'s thermal conduction study meeting (HEI) is recommended often through empirical equation
Formula, the other Germania empirical equation of thermal technology institute of the former Soviet Union and Britain's BEAMA formula.
Then after cooling water inlet temperature is determined, condenser pressure P can be determined by (1) formulacCorresponding saturated vapor temperature
Spend ts, and then by (4) formula or look into vapor table and determine condenser pressure Pc。
(2) intelligent diagnostics
Using BP neural network, population BP neural network, based on intelligent algorithms such as vector machine recurrence, data fusions come really
Determine norm vacuum.Its input parameter has to be judged to influence condenser vacuum correlation using the method with multiple linear regression
Big factor;Also have using by parameter-unit current power after the simplification of condenser pressure calculating mechanism, cooling water inlet temperature
Degree, condenser cleaning after the time, put into operation water circulating pump number of units etc.;The turbine discharge that also uses, Inlet Temperature of Circulating Water, follow
Ring water-carrying capacity.On the one hand these methods need great amount of samples to be trained algorithm, and what another aspect input parameter had is difficult to straight
Measurement is connect, what is had has coupling each other, and practical application is inconvenient.
The content of the invention
The present invention be directed to judge the problem of condenser vacuum status method is complicated now, it is proposed that one kind is based on k-M moulds
The condenser vacuum condition discrimination method of type is there is provided a kind of simple and effective method, to determine that condensing steam turbine generator group is coagulated
Vapour device is in a certain operating mode (by unit load Pe, cooling water inlet temperature tw1With cooling water flow DwIt is determined that) under vacuum (or work
Make pressure) it is whether normal.K-M models are that the experiment between condenser heat transfer coefficient k and condenser operating condition relevant parameter M is closed
It is formula.
The technical scheme is that:A kind of condenser vacuum condition discrimination method based on k-M models, specifically include as
Lower step:
1) between the normal heat transfer coefficient of condenser and operating mode dimensionless number M that determine given condensing steam turbine generator group
Relation:
Condenser performance test, measurement data are carried out in the case of given condensing steam turbine generator group normal operation
Including unit load Pe, cooling water flow Dw, condenser pressure pc, cooling water inlet temperature tw1And exit water temperature tw2, and pass through
Table look-up or the mode of software obtains recirculated water specific heat capacity c under each operating modepWith the saturation pressure t under condenser pressures, substitute into
Formula below tries to achieve the normal heat transfer coefficient k of condenserc,
Wherein AcFor the heat exchange area of condenser;
Defining condenser operating condition relevant parameter is
Pass through experimental data, the normal heat transfer coefficient k of fitting condensercRelation between M is:
kc=aMb
Wherein a, b are and cooling water flow DwRelated coefficient, finally obtains fitting kcMaximum relative error be Δ;
2) operating mode, i.e. unit load Pe, cooling water flow D are givenw, cooling water inlet temperature tw1It is normal to condenser is fixed
The determination of heat transfer coefficient:
With the unit load Pe of given operating mode, cooling water inlet temperature tw1, cooling water flow DwDimensionless number M is calculated, by M
Bring normal heat transfer coefficient k after fitting intocFormula can be calculated the normal heat transfer coefficient k of condenser under the operating conditionc;
3) in step 2) determination of the actual heat transfer coefficient of condenser under given operating mode:
In unit load Pe, cooling water flow Dw, cooling water inlet temperature tw1And on the premise of giving, measure condenser pressure
Power pc, coolant outlet water temperature tw2, table look-up or software by way of obtain recirculated water specific heat capacity c under each operating modepWith it is solidifying
Saturation pressure t under vapour device pressures, and then try to achieve the actual heat transfer coefficient k of condenserc',
4) in step 2) give whether condenser vacuum under operating mode normally judges:
The deviation for defining actual heat transfer coefficient and normal heat transfer coefficient is
IfThen condenser vacuum is abnormal;IfThen
Think that condenser vacuum is normal.
The beneficial effects of the present invention are:The condenser vacuum condition discrimination method based on k-M models of the invention, it is and existing
Technology is compared, and the present invention is not necessary to know the specific physical dimension of condenser for given actual set, can according to it is limited just
The test data of normal operating mode can be just judged all operating modes of unit so that the judgement of condenser working condition is more simple
It is single.
Brief description of the drawings
Fig. 1 is the specific measuring method of the present invention and its a typical condensing steam turbine generator system system signal of application
Figure.
Embodiment
The specific measuring method of the present invention as shown in Figure 1 and its an exemplary situations --- the steam turbine generator system of application
System:Steam 1 enters steam turbine 2 expansion work and drives generator 3 to generate electricity, and steam discharge enters condenser 13, the water cooling that is cooled into
It is cooling water inlet pipeline for condensate 12,9,8 be coolant outlet pipeline, and condenser is left after cooling water heating.In cooling
Test point 7, detection coolant outlet water temperature t are set on water outlet line 8w2, two tests are set on cooling water inlet pipeline 9
Point 10,11, detects cooling water inlet temperature t respectivelyw1With cooling water flow Dw, the output end setting test point 4 of generator 3, inspection
Unit load Pe is surveyed, all numbers of test points evidences send computing unit 6,5 to be electromotive power output.The inventive method is concretely comprised the following steps:
(1) relation between the normal heat transfer coefficient of certain unit condenser and operating mode dimensionless number M is determined:
For given condensing steam turbine generator group, Performance of Condensers examination is carried out in the case of unit operation is normal
Test.Measurement data includes unit load Pe, cooling water flow Dw, condenser pressure pc, cooling water inlet temperature tw1And go out saliva
Warm tw2Deng Specifeca tion speeification, and table look-up or software by way of obtain recirculated water specific heat capacity c under each operating modepAnd condensing
Saturation pressure t under device pressures.And then the normal heat transfer coefficient k of condenser is tried to achieve according to formula (5)c。
Wherein AcFor the heat exchange area of condenser.
Defining condenser operating condition relevant parameter is
Pass through experimental data, the normal heat transfer coefficient k of fitting condensercRelation between M is
kc=aMb (6)
Wherein a, b are and cooling water flow DwRelated coefficient, the maximum relative error of fitting formula is Δ.
(2) certain operating mode (i.e. unit load Pe, cooling water flow Dw, cooling water inlet temperature tw1It is given) under condenser it is normal
The determination of heat transfer coefficient:
According to unit load Pe, cooling water inlet temperature tw1, cooling water flow DwCalculate dimensionless number M;
Bring M into normal heat transfer coefficient k that formula (6) can be calculated condenser under the operating conditionc。
(3) determination of the actual heat transfer coefficient of condenser under operating mode is determined in above-mentioned (2):
In unit load Pe, cooling water flow Dw, cooling water inlet temperature tw1On the premise of given, condenser pressure is measured
pc, coolant outlet water temperature tw2Deng Specifeca tion speeification, table look-up or software by way of obtain recirculated water under each operating mode
Specific heat capacity cpWith the saturation pressure t under condenser pressures.And then try to achieve the actual heat transfer coefficient k of condenserc’。
(4) fix whether condenser vacuum normally judges in above-mentioned (2):
The deviation for defining actual heat transfer coefficient and normal heat transfer coefficient is
IfThen condenser vacuum is abnormal;IfThen
Think that condenser vacuum is normal.
This method calculates illustration:
1st, known conditions
By taking the condenser of certain 1000MW Steam Turbine as an example.The supporting condenser model N-54000 of this unit, cooling surface
Product is 54000m2.Due to being configured cooling water, cooling water flow only has a kind of 27.604kg/s.
2nd, k is determined according to accidental conditions experimentcWith M relational expression
Under normal running (operation) conditions, the condenser service data under 5 operating modes of unit is measured with test method(s), as shown in table 1.
And according toWithCalculate kcTable 1, wherein c are included in M valuespAccording to
tw1The specific heat capacity of the water of determination.
Table 1
According to kc=aMbPower function relationship be fitted normal heat transfer coefficient kcRelational expression with M is:kc=94.327M-1.1464
Maximum relative error Δ=1.412% of fitting formula
3rd, under monitoring condenser actual operating mode, the normal heat transfer coefficient of condenser and the actual heat transfer coefficient of condenser are determined
Deviation as shown in table 2, cooling water flow is 27.604kg/s.
The wherein normal heat transfer coefficient k of condenserc=94.327M-1.1464
The actual heat transfer coefficient of condenser
Table 2
Then operating mode 1-3 condenser heat transfer coefficient deviation is more than 1.1 Δ=1.6%, belongs to the abnormal shape of condenser vacuum
Condition;And the condenser heat transfer coefficient deviation of operating mode 4 is less than 1.1 Δ=1.6%, condenser vacuum is normal.This and actual conditions phase
Symbol.
Claims (1)
1. a kind of condenser vacuum condition discrimination method based on k-M models, it is characterised in that specifically include following steps:
1) pass between the normal heat transfer coefficient of condenser and operating mode dimensionless number M of given condensing steam turbine generator group is determined
System:
Condenser performance test is carried out in the case of given condensing steam turbine generator group normal operation, measurement data includes
Unit load Pe, cooling water flow Dw, condenser pressure pc, cooling water inlet temperature tw1And exit water temperature tw2, and by tabling look-up
Or the mode of software obtains the recirculated water specific heat capacity c under each operating modepWith the saturation pressure t under condenser pressures, substitute into following
Formula tries to achieve the normal heat transfer coefficient k of condenserc,
<mrow>
<msub>
<mi>k</mi>
<mi>c</mi>
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</mrow>
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</msub>
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<mi>t</mi>
<mrow>
<mi>w</mi>
<mn>2</mn>
</mrow>
</msub>
</mrow>
</mfrac>
</mrow>
Wherein AcFor the heat exchange area of condenser;
Defining condenser operating condition relevant parameter is
Pass through experimental data, the normal heat transfer coefficient k of fitting condensercRelation between M is:
kc=aMb
Wherein a, b are and cooling water flow DwRelated coefficient, finally obtains fitting kcMaximum relative error be Δ;
2) operating mode, i.e. unit load Pe, cooling water flow D are givenw, cooling water inlet temperature tw1Normally conducted heat to condenser is fixed
The determination of coefficient:
With the unit load Pe of given operating mode, cooling water inlet temperature tw1, cooling water flow DwCalculate condenser operating condition phase
Related parameter M, brings M into after fitting normal heat transfer coefficient kcFormula can be calculated the normal heat transfer system of condenser under the given operating mode
Number kc;
3) in step 2) determination of the actual heat transfer coefficient of condenser under given operating mode:
In unit load Pe, cooling water flow Dw, cooling water inlet temperature tw1On the premise of given, condenser pressure p is measuredc, it is cold
But water out water temperature tw2, table look-up or software by way of obtain recirculated water specific heat capacity c under each operating modepAnd condenser pressure
Under saturation pressure ts, and then try to achieve the actual heat transfer coefficient k of condenserc',
<mrow>
<msup>
<msub>
<mi>k</mi>
<mi>c</mi>
</msub>
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<mi>c</mi>
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</mrow>
<msub>
<mi>A</mi>
<mi>c</mi>
</msub>
</mfrac>
<mo>&CenterDot;</mo>
<mi>l</mi>
<mi>n</mi>
<mfrac>
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<msub>
<mi>t</mi>
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</msub>
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4) in step 2) give whether condenser vacuum under operating mode normally judges:
The deviation for defining actual heat transfer coefficient and normal heat transfer coefficient is
IfThen condenser vacuum is abnormal;IfThen think solidifying
Vapour device vacuum is normal.
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CN108362329A (en) * | 2018-01-23 | 2018-08-03 | 华电国际电力股份有限公司技术服务中心 | Steam condenser of steam turbine set end difference abnormity diagnostic system and method |
CN109580241B (en) * | 2018-12-07 | 2021-01-15 | 宝武集团鄂城钢铁有限公司 | Quantitative analysis method for pollution degree of condenser |
CN112069650B (en) * | 2020-07-21 | 2023-08-18 | 国网河北省电力有限公司电力科学研究院 | Condenser performance evaluation method and terminal equipment |
CN116029134B (en) * | 2023-01-09 | 2023-11-28 | 华能苏州热电有限责任公司 | Method for establishing heat transfer model of condenser under different operation conditions |
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US3882715A (en) * | 1973-07-05 | 1975-05-13 | Treadwell Corp | Air leak detector |
DD148383A1 (en) * | 1979-12-27 | 1981-05-20 | Barbara Ehlig | METHOD FOR LEAK DETECTION OF VACUUM SYSTEMS |
CN101825502B (en) * | 2010-04-16 | 2011-10-05 | 东南大学 | Effluent and drain temperature measurement and calculation method of heater with drain cooler on steam turbine |
CN202024865U (en) * | 2011-04-26 | 2011-11-02 | 山东电力研究院 | On-line detection device for air leakage quantity of vacuum system of steam turbine generator unit |
CN102305553B (en) * | 2011-08-12 | 2012-09-26 | 浙江省电力试验研究院 | Determination method of total heat transfer coefficient of condenser of thermal generator set |
CN102338568B (en) * | 2011-09-20 | 2014-01-08 | 河北省电力建设调整试验所 | Online monitoring system and method for performance of condenser in power plant based on cleanness coefficient index |
CN202471131U (en) * | 2012-03-01 | 2012-10-03 | 河北省电力研究院 | System for carrying out real-time monitoring on performance of steam condenser for power plants |
CN103389743B (en) * | 2013-07-23 | 2015-06-17 | 国家电网公司 | Method for considering real-time operation cleanness factors of condenser and improving efficiency of generating set |
CN103499371B (en) * | 2013-09-27 | 2016-08-17 | 西安热工研究院有限公司 | A kind of measure condenser and method that vacuum system leaks into air mass flow |
CN104992066B (en) * | 2015-07-14 | 2017-08-25 | 上海电力学院 | Condenser heat transfer coefficient computational methods based on two dimensionless numbers |
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