CN106382615A - Verification system and method for ultra-supercritical unit multi-time reheat steam temperature control strategy - Google Patents
Verification system and method for ultra-supercritical unit multi-time reheat steam temperature control strategy Download PDFInfo
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- CN106382615A CN106382615A CN201610729603.4A CN201610729603A CN106382615A CN 106382615 A CN106382615 A CN 106382615A CN 201610729603 A CN201610729603 A CN 201610729603A CN 106382615 A CN106382615 A CN 106382615A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
- F22B35/00—Control systems for steam boilers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22G—SUPERHEATING OF STEAM
- F22G5/00—Controlling superheat temperature
- F22G5/04—Controlling superheat temperature by regulating flue gas flow, e.g. by proportioning or diverting
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B23/00—Testing or monitoring of control systems or parts thereof
- G05B23/02—Electric testing or monitoring
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- Thermal Sciences (AREA)
- Control Of Steam Boilers And Waste-Gas Boilers (AREA)
Abstract
The invention relates to a verification system and method for an ultra-supercritical unit multi-time reheat steam temperature control strategy. Before a unit is put into operation, through the ultra-supercritical unit multi-time reheat steam temperature dynamic simulation environment, the reheat steam temperature control logics including flue gas recirculation, a swing combustor and a flue gas baffle are verified and optimized, so that the starting adjusting time of the real unit is shortened; and meanwhile, the problem that the optimization and adjustment test is limited by operation conditions when carried out on the real unit after the real unit is put into operation is solved. The system comprises a master computer, a dynamic simulation environment model, a virtual control station computer, the multi-time reheat steam temperature control logics, a virtual controller VDCS, a human-computer interface and I/O communication software. By means of the method of introducing the fineness of pulverized coal, the oxygen content, the n-time reheat steam pressures and the steam temperature correction set value, the reheat steam temperature control logics are optimized, so that high-quality control over the ultra-supercritical unit multi-time reheat steam temperature is achieved, and the needs of the ultra-supercritical multi-time reheat unit for safe, stable and efficient operation are met.
Description
Technical field:
The invention belongs to power station extra-supercritical unit automatic control technology field is and in particular to a kind of extra-supercritical unit is many
Secondary Switching Logic Control of Reheat Steam Temperature policy validation system and method.
Background technology
The resources characteristic of China's " rich coal, oil-poor, few gas ", determines coal fired power generation in China's energy resource structure mainly
Position.In the face of China's rapid economic development, the immense pressure of electricity needs and environmental protection proposes new to China's energy-saving and emission-reduction
Require, and improve the generating efficiency of thermal power plant, reduce gross coal consumption rate, the application of ultra supercritical double reheat technology will be from source
The upper most effective means reducing flue gas pollutant and CO2 emission;And full-fledged with double reheat technology,
It is possible that three thermal technologies again.But the growth of ultra supercritical double reheat power generation sets carbonated drink flow process, Boiler Convection Heating Surface level
Number increases, arrangement is more complicated, and the sound state response characteristic of unit occurs large change, and reheat steam temperature surpasses 600 DEG C and connects simultaneously
Nearly metal material allows temperature upper limit, and Switching Logic Control of Reheat Steam Temperature allowance reduces, and the control of extra-supercritical unit double reheat steam temperature
Method processed changes greatly compared with single reheat unit.Due to system complex, each control loop of machine, stove for example wind, coal, feedwater, steam temperature and
There is very strong nonlinear coupling relationship between spatial load forecasting, and the change influence factor of reheat steam temperature is more.For guaranteeing to surpass
The smooth operation of supercritical double-reheat unit and safe and reliable operation, before actual set debugging, running, to according to theoretical point
The double reheat Superheated Steam Temperature Control Strategy of analysis and engineering experience design is verified and is optimized, and provides reference number for actual set construction
Have very important significance according to guidance, in the urgent need to a kind of effective and reliable method of research.
Domestic to resuperheat unit allocation strategy study of ultra supercritical, before unit operation rest on to part more
Control loop and related therrmodynamic system carry out mechanistic modeling and analysis level, often assume and simplified condition is more, be confined to
Only it is provided that tendency instructs.How to be optimized Adjustment Tests analysis method using to actual set after unit operation, but be subject to
Limit to unit operation condition and can not be tested arbitrarily, at any time in big load range, so far also not at the beginning of Construction of Unit
Phase is directed to the extra-supercritical unit double reheat Superheated Steam Temperature Control Strategy checking system of practical engineering application and the research of method.
Content of the invention
For the problem overcoming above-mentioned prior art to exist, it is an object of the invention to provide a kind of extra-supercritical unit is many
Secondary Switching Logic Control of Reheat Steam Temperature policy validation system and method, passes through the multiple reheat steam temperature of extra-supercritical unit before unit commitment runs
Dynamic simulation environment, control logic to the multiple reheat steam temperature of extra-supercritical unit (include tilting burner, flue gas recirculation,
Gas baffle and spray desuperheating control) verified and optimized, it is debugging and the operation of the multiple reheating embrittlement of extra-supercritical unit
Basic data and guidance are provided, realize shortening unit regulation time, the multiple reheat steam temperature of effective control extra-supercritical unit fair
It is ensured that the purpose of extra-supercritical unit safety, economy and stable operation in the range of being permitted.
To achieve these goals, the present invention employs the following technical solutions:
A kind of multiple Switching Logic Control of Reheat Steam Temperature policy validation system of extra-supercritical unit, communicates soft including master computer 1, I/O
The virtual controlling station computer 3 that part 7 is connected with master computer 1, is dynamic simulation environmental model 2 in described master computer 1, virtual
For multiple Switching Logic Control of Reheat Steam Temperature logic 4, Virtual Controller VDCS 5 and man-machine interface 6 in control station computer 3;I/O communication is soft
Part 7 realizes the real-time data communication between dynamic simulation environmental model 2 and virtual controlling station computer 3;Described master computer 1 from
Virtual controlling station computer 3 obtain operating personnel issue by man-machine interface 6 tilting burner, flue gas recirculation, flue gas keep off
Plate and the instruction of spray desuperheating control operation, and result of calculation is included:Flue gas recirculation baffle opening, tilting burner angle,
Gas baffle aperture and desuperheat spray flow, n reheat steam temperature and unit real time execution analog parameter feed back to virtual controlling station
Computer 3, forms closed-loop control.
With dynamic simulation environmental model 2 as core, dynamic simulation environmental model 2 is overall process dynamic analog to master computer 1
Ultra supercritical multiple reheating embrittlement body process model, realize to reference to unit from cold start to operating mode at full capacity and
From operating mode at full capacity to halted state overall process real time dynamic simulation.
Described dynamic simulation environmental model 2 adopts larger fluid network algorithm, is meeting mass conservation law, the conservation of energy
It is ensured that the integrality of model based on Physical Mechanism, accuracy and real-time on the premise of law, the law of conservation of momentum;Truly
Each physical process of simulation actual set, including the energy conversion process in unit running process and working medium in not equality of temperature
Physical characteristic under degree and pressure.
A kind of verification method of extra-supercritical unit multiple Switching Logic Control of Reheat Steam Temperature policy validation system described above, described
Repeatedly it is attached in Virtual Controller VDCS 5 under Switching Logic Control of Reheat Steam Temperature logic 4, content includes:Flue gas recirculation baffle plate, swing combustion
Burner, gas baffle and spray desuperheating control;Comprise the following steps that:
1st step:Operating personnel set ultra supercritical reheating embrittlement total load by man-machine interface 6;
2nd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is by obtaining dynamic simulation environmental model 2 by I/O bitcom 7
Fineness of pulverized coal, oxygen content measurement signal;
3rd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculates correction factor C according to fineness of pulverized coal, oxygen amount1, C1=(1-
0.02*(R90-18)/18)*(3.35*(O2-O2 r)), wherein R90For fineness of pulverized coal, O2For burner hearth flue gas oxygen content, O2 rRepresent machine
Group declared working condition flue gas oxygen content, the O as unit load≤300MW2 rFor 5.56, O during unit load=500MW2 rFor 4.33,
O during unit load=750MW2 rFor 3.2, O during unit load=1000MW2 rFor 2.74;And to C1Carry out upper lower limit value,
0.992≤C1≤1.008;
4th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is by obtaining dynamic simulation environmental model 2 by I/O bitcom 7
1 ... n reheat pressure, temperature measurement signal;
5th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is according to 1...n reheat pressure, temperature computation correction factor C2;First
Calculate the enthalpy h of corresponding temperature and pressurenF (Pn,Tn), C2K3((h1-h1 r)+(h2-h2 r)+┄+(hn-hn r)), to secondary again
Heat engine group n=2, wherein P are pressure, and T is temperature, and h is enthalpy;Coefficient k3Span 500~510;And to C2Carry out up and down
Limit value, 0.988≤C2≤1.012;
6th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculating reheat steam temperature initial set value X, X=C1*C2*f (x), wherein
F (x) determines according to unit total load, is 480 DEG C as unit total load < 400MW, as unit total load >=400MW and <
When being 545 DEG C during 600MW, when unit total load >=600MW is 623 DEG C;
7th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 carries out high-low limits calculating to reheat steam temperature initial set value X, obtains
Dynamic setting value Ts of reheat steam temperature, wherein higher limit max (x):It is 520 DEG C as unit total load < 400MW, when unit is always born
Lotus >=400MW is 628 DEG C;Lower limit min (x):As unit total load < 400MW be 460 DEG C, when unit total load >=
When being 525 DEG C during 400MW and < 600MW, when unit total load >=600MW is 603 DEG C, min (x)≤Ts≤max (x);
8th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is by obtaining dynamic simulation environmental model 2 by I/O bitcom 7
1 ... n reheat steam temperature measured value T1~Tn;
9th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is by n reheat steam temperature measured value T1~TnAverage computation obtain
Reheat steam temperature measured value T;
10th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculates dynamic setting value T of reheat steam temperatureSWith reheat steam temperature measured value T
Deviation;
11st step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 passes through PID regulator ratio, integration, differential calculation, exports flue gas
Recycle opening amount signal;
12nd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is by obtaining dynamic simulation environmental model 2 by I/O bitcom 7
Steam-water separator pressure measurement signal;
13rd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 sets flue gas recirculation baffle opening and believes as boiler main fuel trip
Number occur when corresponding flue gas recirculation baffle opening definite value;
14th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 sets flue gas recirculation baffle plate when recirculation blower stops and opens as 0%
Degree;
15th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 output flue gas recirculation baffle opening instruction, reaches adjustment flue gas again
Internal circulating load purpose;
16th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 passes through PID regulator ratio, integration, differential calculation, calculates burning
Device swash angle position;
17th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 sets burner swash angle position and sends out as boiler main fuel trip signal
Steam-water separator pressure corresponding definite value when raw;
18th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 output burner swash angle position instruction, thus reach adjustment burner hearth fire
The purpose of flame center;
19th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculates n reheat steam temperature measured value T respectively1~TnWith reheat steam temperature
Dynamic setting value TSDeviation;
20th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculates the mean value of n reheat steam temperature deviation;
21st step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is opened by PID regulator ratio, integration, differential calculation gas baffle
Degree;
22nd step:When boiler main fuel trip signal occurs, multiple Switching Logic Control of Reheat Steam Temperature logic 4 sets gas baffle and opens
Spend for 50%, that is, be maintained at centre position;
23rd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is calculated 1 by partition function~N grade low-temp reheater flue gas keeps off
Plate opening degree instruction;
24th step:Instructed according to flue gas recirculation baffle opening by dynamic simulation environmental model 2 and calculate flue gas recycled amount;
25th step:Furnace flame center is calculated according to burner swash angle position by dynamic simulation environmental model 2;
26th step:By dynamic simulation environmental model 2 according to 1~N level reheater gas baffle aperture calculates passes through 1~N level is low
Warm reheater exhaust gas volumn;
27th step:1~n time reheat steam temperature is calculated by dynamic simulation environmental model 2.
Said method increased fineness of pulverized coal, flue gas oxygen content and n time again in multiple Switching Logic Control of Reheat Steam Temperature logic 4
Hot vapour pressure and the correction to the dynamic setting value of multiple reheat steam temperature for the steam temperature factor, reflect the various of impact reheat steam temperature with this comprehensively
Factor, the high-quality realizing reheat steam temperature controls;Not only it is suitable for ultra supercritical double reheat power generation sets Switching Logic Control of Reheat Steam Temperature strategy to test
Card and optimization, and it is suitable for extra-supercritical unit Switching Logic Control of Reheat Steam Temperature policy validation and the optimization of more stages reheating.
Compared to the prior art relatively, the present invention has the advantages that:
620 DEG C of grade ultra supercritical double reheat Thermal generation unit still belong to tentative unit in the world, and unit is normal
During operation, the nargin between the limiting temperature of metal material and design temperature is less, explores and is suitable for ultra supercritical double reheat power generation sets
Control strategy, can by first and second Switching Logic Control of Reheat Steam Temperature in the reasonable scope, be ultra supercritical double reheat power generation sets stable,
Safety and Effec-tive Function provide reliable reference data and technological guidance.By the present invention:
1. build the multiple reheating embrittlement of ultra supercritical close to Practical Project and run simulated environment, a kind of ultra supercritical is provided
Repeatedly Switching Logic Control of Reheat Steam Temperature policy validation system and method.
2. checking flue gas recirculation, burner pivot angle, the affecting laws to multiple reheat steam temperature for the flue gas distributor aperture,
Verify that it controls the reasonability of configuration logic design and is optimized, provide reference and prediction for practical engineering application.
3. it is the overall control strategy design in startup, normal operation, accident conditions for the multiple reheating embrittlement of ultra supercritical
And offer basic data is provided.
Brief description
Fig. 1 is checking system structure chart.
Fig. 2 is double reheat carbonated drink general flow chart.
Fig. 3 is multiple Switching Logic Control of Reheat Steam Temperature logic diagram.
It is embodied as
The present invention will be described in more detail below in conjunction with the accompanying drawings.
As shown in figure 1, being extra-supercritical unit multiple Switching Logic Control of Reheat Steam Temperature policy validation system construction drawing, including host computer
Machine 1, dynamic simulation environmental model 2, virtual controlling station computer 3, multiple Switching Logic Control of Reheat Steam Temperature logic 4, Virtual Controller VDCS
5th, man-machine interface 6 and I/O bitcom 7.I/O bitcom 7 by I/O map mapping mechanism realize master computer 1 with virtual
Real-time data communication between control station computer 3.Described master computer 1 obtains operating personnel from virtual controlling station computer 3
Tilting burner, flue gas recirculation, gas baffle and the instruction of spray desuperheating control operation being issued by man-machine interface;And will lead
Computer 1 result of calculation, including:Tilting burner angle, flue gas recirculation baffle opening, gas baffle aperture and spray desuperheating
Flow, n reheat steam temperature (to double reheat power generation sets n=2) and unit real time execution analog parameter feed back to virtual controlling station meter
Calculation machine 3, forms close loop control circuit.
Dynamic simulation environmental model 2 is the ultra supercritical double reheat power generation sets body process model of overall process dynamic analog,
Realize with reference to unit from Shang Shui, ventilation, igniting, intensification, boosting, warming-up, grid-connected, load up overall process real time dynamic simulation.Dynamic
State simulated environment model 2 is larger fluid network algorithm, and meeting, mass conservation law, law of conservation of energy, the conservation of momentum are fixed
It is ensured that the integrality of model based on Physical Mechanism, accuracy and real-time on the premise of rule.True simulation actual set
Each physical process, including the energy conversion process in unit running process and working medium physics at different temperatures and pressures
Characteristic.
By virtual controlling station computer 3 software (now unit DCS group is obtained to the translation of unit DCS configuration project file
State completes, but does not have started field adjustable), including man-machine interface 2 and Virtual Controller VDCS 5, the simulation of VDCS 5 software is actual
The calculating process of DPU control logic export operation result in unit DCS system.
It is attached in Virtual Controller VDCS 5 under above-mentioned multiple Switching Logic Control of Reheat Steam Temperature logic 4, content includes:Swing burning
Device, flue gas recirculation, gas baffle and spray desuperheating control;In addition by the adjustment of boiler operating parameter, such as fineness of pulverized coal,
The means such as oxygen amount, burner combination, OFA operation mode of running also can achieve certain reheat steam temperature adjustment effect, this
Bright increased fineness of pulverized coal in multiple Switching Logic Control of Reheat Steam Temperature logic 4, run oxygen amount and n reheat steam pressure and temperature
The correction to the dynamic setting value of multiple reheat steam temperature for the factor.As shown in figure 3, concrete calculation procedure is as follows:
1st step:Operating personnel set ultra supercritical reheating embrittlement total load by man-machine interface 6;
2nd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 obtains dynamic simulation environmental model 2 coal dust by I/O bitcom 7
Fineness, oxygen content measurement signal;
3rd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculates correction factor C according to fineness of pulverized coal, oxygen amount1, C1=(1-
0.02*(R90-18)/18)*(3.35*(O2-O2 r)), wherein R90For fineness of pulverized coal, O2For burner hearth flue gas oxygen content, O2 rRepresent machine
Group declared working condition flue gas oxygen content, the O as unit load≤300MW2 rFor 5.56, O during unit load=500MW2 rFor 4.33,
O during unit load=750MW2 rFor 3.2, O during unit load=1000MW2 rFor 2.74;And to C1Carry out upper lower limit value,
0.992≤C1≤1.008;
4th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 obtains the 1 of dynamic simulation environmental model 2 by I/O bitcom 7 ...
N reheat pressure, temperature measurement signal;
5th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is according to 1...n reheat pressure, temperature computation correction factor C2;First
Calculate the enthalpy h of corresponding temperature and pressurenF (Pn,Tn), C2K3((h1-h1 r)+(h2-h2 r)+┄+(hn-hn r)), to secondary again
Heat engine group n=2, wherein P are pressure, and T is temperature, and h is enthalpy;Coefficient k3Span 500~510;And to C2Carry out up and down
Limit value, 0.988≤C2≤1.012;
6th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculating reheat steam temperature initial set value X, X=C1*C2*f (x), wherein
F (x) determines according to unit total load, is 480 DEG C as unit total load < 400MW, as unit total load >=400MW and <
When being 545 DEG C during 600MW, when unit total load >=600MW is 623 DEG C;
7th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 carries out high-low limits calculating to reheat steam temperature initial set value X, obtains
Dynamic setting value Ts of reheat steam temperature, wherein higher limit max (x):It is 520 DEG C as unit total load < 400MW, when unit is always born
Lotus >=400MW is 628 DEG C;Lower limit min (x):As unit total load < 400MW be 460 DEG C, when unit total load >=
When being 525 DEG C during 400MW and < 600MW, when unit total load >=600MW is 603 DEG C, min (x)≤Ts≤max (x);
8th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 obtains the 1 of dynamic simulation environmental model 2 by I/O bitcom 7 ...
N reheat steam temperature measured value;
9th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is by n reheat steam temperature measured value T1~TnAverage computation obtain
Reheat steam temperature measured value T;
10th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculates dynamic setting value T of reheat steam temperaturesWith reheat steam temperature measured value T
Deviation;
11st step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 passes through PID regulator ratio, integration, differential calculation, exports flue gas
Recycle opening amount signal;
12nd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 obtains dynamic simulation environmental model 2 carbonated drink by I/O bitcom 7
Separator pressure measurement signal;
13rd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 sets flue gas recirculation baffle opening and believes as boiler main fuel trip
Number occur when corresponding flue gas recirculation baffle opening definite value;
14th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 sets flue gas recirculation baffle plate when recirculation blower stops and opens as 0%
Degree;
15th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 output flue gas recirculation baffle opening instruction, reaches adjustment flue gas again
Internal circulating load purpose;
16th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 passes through PID regulator ratio, integration, differential calculation, calculates burning
Device swash angle position;
17th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 sets burner swash angle position and sends out as boiler main fuel trip signal
Steam-water separator pressure corresponding definite value when raw;
18th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 output burner swash angle position instruction, thus reach adjustment burner hearth fire
The purpose of flame center;
19th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculates n reheat steam temperature measured value T respectively1~TnWith reheat steam temperature
Dynamic setting value TSDeviation;
20th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculates the mean value of n reheat steam temperature deviation;
21st step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is opened by PID regulator ratio, integration, differential calculation gas baffle
Degree;
22nd step:When boiler main fuel trip signal occurs, multiple Switching Logic Control of Reheat Steam Temperature logic 4 sets gas baffle and opens
Spend for 50%, that is, be maintained at centre position;
23rd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 is calculated 1 by partition function~N grade low-temp reheater flue gas keeps off
Plate opening degree instruction;
24th step:Instructed according to flue gas recirculation baffle opening by dynamic simulation environmental model 2 and calculate flue gas recycled amount;
25th step:Furnace flame center is calculated according to burner swash angle position by dynamic simulation environmental model 2;
26th step:By dynamic simulation environmental model 2 according to 1~N level reheater gas baffle aperture calculates passes through 1~N level is low
Warm reheater exhaust gas volumn;
27th step:1~n time reheat steam temperature is calculated by dynamic simulation environmental model 2.
Embodiment:
Certain ultra supercritical double reheat power generation sets boiler is direct current this life stove, resuperheat twice.Steam turbine adopt superelevation/height/
Intermediate pressure cylinder combined launch mode, main steam be serial flow, that is, main steam by ultra-high pressure cylinder VHP entrance → steam discharge to one-level reheating
Device → entrance high pressure cylinder HP → high pressure cylinder HP steam discharge is to two grades of reheater → entrance intermediate pressure cylinder IP → low pressure (LP) cylinder LP → condensers, machine
Group carbonated drink general flow chart is shown in Fig. 2.According to unit process engineering ultra supercritical double reheat power generation sets Switching Logic Control of Reheat Steam Temperature logic,
By extra-supercritical unit multiple Switching Logic Control of Reheat Steam Temperature policy validation system, carry out unit starting, stopped process is dynamically imitated in real time
True test, according to flue gas recirculation, the burner pivot angle and gas baffle Different Effects to first and second reheat steam temperature dynamic characteristic
Adjust respectively each PID regulator parameter, the closed-loop control of flue gas recirculation, burner pivot angle and gas baffle is realized with this.Logical
Cross flue gas recirculation, burner pivot angle changes the heat distribution between superheater and reheater;Passed through by gas baffle adjustment
Exhaust gas volumn between I and II low pressure reheater, controls first and second reheat steam temperature deviation to reach setting value.Reheater water injection is only
Use during as reheat steam temperature accident condition, do not use during normal operation, therefore not as the emphasis of checking.In actual set fortune
Before the row debugging stage, the checking of Switching Logic Control of Reheat Steam Temperature logic and optimization are realized by the method it is ensured that first and second reheat steam temperature control
Logic processed had not only met production needs but also can guarantee that equipment safety.
Claims (5)
1. a kind of multiple Switching Logic Control of Reheat Steam Temperature policy validation system of extra-supercritical unit it is characterised in that:Including master computer
(1) virtual controlling station computer (3) that, I/O bitcom (7) is connected with master computer (1), in described master computer (1) be
Dynamic simulation environmental model (2), is multiple Switching Logic Control of Reheat Steam Temperature logic (4), Virtual Controller in virtual controlling station computer (3)
VDCS (5) and man-machine interface (6);I/O bitcom (7) realizes dynamic simulation environmental model (2) and virtual controlling station computer
(3) real-time data communication between;Described master computer (1) obtains operating personnel from virtual controlling station computer (3) and passes through people
Tilting burner, flue gas recirculation, gas baffle and the instruction of spray desuperheating control operation that machine interface (6) issues, and will calculate
Result includes:Flue gas recirculation baffle opening, tilting burner angle, gas baffle aperture and desuperheat spray flow, n reheating
Steam temperature and unit real time execution analog parameter feed back to virtual controlling station computer (3), form closed-loop control.
2. the multiple Switching Logic Control of Reheat Steam Temperature policy validation system of a kind of extra-supercritical unit according to claim 1, its feature
It is:With dynamic simulation environmental model (2) as core, dynamic simulation environmental model (2) is overall process dynamic analog to master computer (1)
Intend ultra supercritical multiple reheating embrittlement body process model, realize to reference to unit from cold start to operating mode at full capacity, with
And from operating mode at full capacity to halted state overall process real time dynamic simulation.
3. the multiple Switching Logic Control of Reheat Steam Temperature policy validation system of a kind of extra-supercritical unit according to claim 1, its feature
It is:Described dynamic simulation environmental model (2) adopts larger fluid network algorithm, is meeting mass conservation law, the conservation of energy
It is ensured that the integrality of model based on Physical Mechanism, accuracy and real-time on the premise of law, the law of conservation of momentum;Truly
Each physical process of simulation actual set, including the energy conversion process in unit running process and working medium in not equality of temperature
Physical characteristic under degree and pressure.
4. the verification method of a kind of extra-supercritical unit multiple Switching Logic Control of Reheat Steam Temperature policy validation system described in claim 1,
It is characterized in that:It is attached in Virtual Controller VDCS (5) under described multiple Switching Logic Control of Reheat Steam Temperature logic (4), content includes:Flue gas
Recycle baffle plate, tilting burner, gas baffle and spray desuperheating to control;Comprise the following steps that:
1st step:Operating personnel set ultra supercritical reheating embrittlement total load by man-machine interface (6);
2nd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) obtains dynamic simulation environmental model (2) coal by I/O bitcom (7)
Powder fineness, oxygen content measurement signal;
3rd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) calculates correction factor C according to fineness of pulverized coal, oxygen amount1, C1=(1-0.02*
(R90-18)/18)*(3.35*(O2-O2 r)), wherein R90For fineness of pulverized coal, O2For burner hearth flue gas oxygen content, O2 rRepresent unit volume
Determine operating mode flue gas oxygen content, the O as unit load≤300MW2 rFor 5.56, O during unit load=500MW2 rFor 4.33, unit
O during load=750MW2 rFor 3.2, O during unit load=1000MW2 rFor 2.74;And to C1Carry out upper lower limit value, 0.992≤
C1≤1.008;
4th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) obtains dynamic simulation environmental model (2) 1 ... by I/O bitcom (7)
N reheat pressure, temperature measurement signal;
5th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) is according to 1...n reheat pressure, temperature computation correction factor C2;First calculate
The enthalpy h of corresponding temperature and pressurenF (Pn,Tn), C2K3((h1-h1 r)+(h2-h2 r)+┄+(hn-hn r)), to double reheat machine
Group n=2, wherein P are pressure, and T is temperature, and h is enthalpy;Coefficient k3Span 500~510;And to C2Carry out bound
Value, 0.988≤C2≤1.012;
6th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) calculates reheat steam temperature initial set value X, X=C1*C2*f (x), wherein f
X () determines according to unit total load, be 480 DEG C as unit total load < 400MW, as unit total load >=400MW and <
When being 545 DEG C during 600MW, when unit total load >=600MW is 623 DEG C;
7th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) carries out high-low limits calculating to reheat steam temperature initial set value X, obtains again
Dynamic setting value Ts of hot vapour temperature, wherein higher limit max (x):It is 520 DEG C as unit total load < 400MW, when unit total load
>=400MW is 628 DEG C;Lower limit min (x):It is 460 DEG C as unit total load < 400MW, as unit total load >=400MW
During with being 525 DEG C during < 600MW, when unit total load >=600MW is 603 DEG C, min (x)≤Ts≤max (x);
8th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) obtains dynamic simulation environmental model (2) 1 ... by I/O bitcom (7)
N reheat steam temperature measured value;
9th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) is by n reheat steam temperature measured value T1~TnAverage computation obtain again
Hot vapour temperature measurements T;
10th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) calculates dynamic setting value T of reheat steam temperaturesWith reheat steam temperature measured value T's
Deviation;
11st step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) passes through PID regulator ratio, integration, differential calculation, and output flue gas is again
Circulation opening amount signal;
12nd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) obtains dynamic simulation environmental model (2) vapour by I/O bitcom (7)
Separator pressure measurement signal;
13rd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) sets flue gas recirculation baffle opening as boiler main fuel trip signal
Corresponding flue gas recirculation baffle opening definite value during generation;
14th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) sets flue gas recirculation baffle plate when recirculation blower stops and opens as 0%
Degree;
15th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) output flue gas recirculation baffle opening instruction, reaches adjustment flue gas and follows
Circular rector purpose;
16th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) passes through PID regulator ratio, integration, differential calculation, calculates burner
Swash angle position;
17th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) sets burner swash angle position and occurs as boiler main fuel trip signal
When the corresponding definite value of steam-water separator pressure;
18th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) output burner swash angle position instruction, thus reach adjustment furnace flame
The purpose of center;
19th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic 4 calculates n reheat steam temperature measured value T respectively1~TnDynamic with reheat steam temperature
Setting value TSDeviation;
20th step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) calculates the mean value of n reheat steam temperature deviation;
21st step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) is opened by PID regulator ratio, integration, differential calculation gas baffle
Degree;
22nd step:When boiler main fuel trip signal occurs, multiple Switching Logic Control of Reheat Steam Temperature logic (4) sets gas baffle aperture
For 50%, that is, it is maintained at centre position;
23rd step:Repeatedly Switching Logic Control of Reheat Steam Temperature logic (4) is calculated 1~n grade low-temp reheater flue gas gear by partition function
Plate opening degree instruction;
24th step:Instructed according to flue gas recirculation baffle opening by dynamic simulation environmental model (2) and calculate flue gas recycled amount;
25th step:Furnace flame center is calculated according to burner swash angle position by dynamic simulation environmental model (2);
26th step:Calculated low by 1~n level according to 1~n level reheater gas baffle aperture by dynamic simulation environmental model (2)
Warm reheater exhaust gas volumn;
27th step:1~n time reheat steam temperature is calculated by dynamic simulation environmental model (2).
5. verification method according to claim 4 it is characterised in that:Multiple Switching Logic Control of Reheat Steam Temperature logic (4) increases
Dynamic setting value is repaiied to multiple reheat steam temperature for fineness of pulverized coal, flue gas oxygen content and n reheat pressure and steam temperature factor
Just, reflect the various factors of impact reheat steam temperature with this, the high-quality realizing reheat steam temperature controls comprehensively;Not only it is suitable for super facing
Boundary's double reheat power generation sets Switching Logic Control of Reheat Steam Temperature policy validation and optimization, and it is suitable for the extra-supercritical unit reheating of more stages reheating
Superheated Steam Temperature Control Strategy checking and optimization.
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