CN109062037A - One kind is based on the dispersion modified fossil power plant auxiliary engine RUNBACK control method of calorific value - Google Patents
One kind is based on the dispersion modified fossil power plant auxiliary engine RUNBACK control method of calorific value Download PDFInfo
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- CN109062037A CN109062037A CN201810705249.0A CN201810705249A CN109062037A CN 109062037 A CN109062037 A CN 109062037A CN 201810705249 A CN201810705249 A CN 201810705249A CN 109062037 A CN109062037 A CN 109062037A
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- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B13/00—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion
- G05B13/02—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric
- G05B13/04—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators
- G05B13/042—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators in which a parameter or coefficient is automatically adjusted to optimise the performance
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Abstract
It is especially a kind of based on the dispersion modified fossil power plant auxiliary engine RUNBACK control method of calorific value the present invention relates to coal-fired power generation field.Pulverizer capacity deficiency and unit RUNBACK target value after burning the lower set auxiliary machinery RUNBACK action triggers of operation are mixed for current coal mismatches contradiction, the present invention provides a kind of based on the dispersion modified fossil power plant auxiliary engine RUNBACK control method of calorific value, burning coal will be mixed particular by calorific value to convert as design coal equivalent, calculate each true load capacity of coal pulverizer, it is added to obtain total fuel capability with the load capacity of each coal pulverizer coal amount corresponding with fuel flow again, fuel load capacity is then scaled by the polygronal function of former logical design；It designs new subsidiary engine RUNBACK target load and calculates control strategy; fuel can on-load ability be lower than former target load design value when switching target load be that Current fuel can on-load; guarantee that unit mixes the major pant item load that surprisingly trips when burning low calorific value coal operation and is down to the load that subsidiary engine can bear, it is ensured that unit is stable, safety.
Description
Technical field
It is especially a kind of based on the dispersion modified fossil power plant auxiliary engine of calorific value the present invention relates to coal-fired power generation field
RUNBACK control method.
Background technique
For the variation for adapting to current power coal market, fossil power plant can all select relatively low low of units of heat price
Medium-heat-value coal reduces production cost.For coal motor group, at present low heat value mix burning mode mainly by low calorific value coal and often
Rule coal is mixed by different mixed-fuel burning proportions or low calorific value coal burns with conventional coal point storehouse, since unit uses coal characteristic
Extensively, a variety of coals may theoretically be used simultaneously in same unit, be that reduction operation complexity is general in actual production
It only mixes and burns a kind of low calorific value coal.At present low heat value mix burning mode mainly by low calorific value coal and conventional coal by different mixed-fuel burning proportions into
Row mixing or low calorific value coal burn with conventional coal point storehouse.The burning of mixing of low calorific value coal will cause coal motor group operating condition when operation
Change, then to subsidiary engine RUNBACK protection tool have a certain impact.Subsidiary engine RUNBACK(RB) it refers to when unit is mainly auxiliary
When machine fault trip causes unit on-load ability to be restricted, to adapt to equipment power output, coordinated control system is forced unit
Load reduces to the process for the load target value that still can bear in the subsidiary engine of operation.After RUNBACK action triggers, coordinate control first
Mode processed automatically switches to turbine follow mode, and unit load is down to target load with the load down rate set.Coal pulverizer
When RUNBACK is acted, target load is set as fuel load capacity, fuel load capacity then by currently running coal pulverizer number of units,
Separate unit coal pulverizer maximum coal-supplying amount and BTU correction coefficient and oil mass are calculated；Primary air fan, give/air-introduced machine, air preheater and
Coal pulverizer trips according to designed sequence when the RUNBACK such as feed pump are acted, and general objectives load is set as 50% rated generation
Power has subtle adjustment according to different unit operating condition differences.
It logically designs in the case where not throwing oil, the maximum coal-supplying amount that current coal-grinding function provides is corrected by BTU
Coefficient is modified to design coal coal amount, is then that load is calculated fuel load capacity using function conversion, every in calculating
Platform coal pulverizer only considers coal-supplying amount without considering that every is ground the coal quality difference used.In operation when the calorific value of coal is lower, separate unit
The unit load that coal pulverizer can undertake is unable to reach the load capacity of conventional coal under identical coal amount, especially mixes burning feelings in Fen Cang
Under condition, load capacity may sharply decline, and in turn result in the practical load capacity of coal pulverizer and calculate the unmatched feelings of load capacity
Condition；Meanwhile the subsidiary engine RUNBACK target load of former logical design is relatively simple, and coal pulverizer occurs surprisingly to trip to be fuel
Then target load can on-load decision according to fuel by RUNBACK；Primary air fan send/air-introduced machine, air preheater and feed pump RB target
Load value is then preset value.But in actual motion, when primary air fan, send/air-introduced machine, air preheater and feed pump RB action triggers,
Coal pulverizer trips according to logical design sequence and delay time, according to the target load of original RUNBACK logic setting, works as reservation
Coal pulverizer be possible to can not be with the target load of full design for fuel capability when using low calorific value coal；Further, from coal pulverizer
From the point of view of safe operation, unit operations staff can tend to keep using as far as possible the coal pulverizer steady-state operation of low calorific value coal,
To prevent coal dust to be trapped in spontaneous combustion in coal pulverizer, pulverizer capacity deficiency and machine after subsidiary engine RUNBACK action triggers are thereby resulted in
Group RUNBACK target value is unmatched particularly thorny, seriously affects the stability and safety of unit operation.
Summary of the invention
The technical problem to be solved in the present invention and the technical assignment of proposition are to solve current low calorific value coal to mix machine under burning is run
Pulverizer capacity deficiency and unit RUNBACK target value be not after group protection control problem, especially subsidiary engine RUNBACK action triggers
Matched conspicuous contradiction provides a kind of based on the dispersion modified fossil power plant auxiliary engine RUNBACK control method of calorific value, the control
Method calculates control strategy by designing new fuel capability, specifically calculates in set auxiliary machinery RUNBACK action triggers
The fuel capability of remaining coal pulverizer, and suitable subsidiary engine RUNBACK target load is selected to export, make so that flexible adaptation is currently practical
Coal quality situation.
The present invention solves the technical solution that technical problem uses: one kind is based on the dispersion modified fossil power plant auxiliary engine of calorific value
RUNBACK control method, including fuel load capacity counter circuit step and design subsidiary engine RUNBACK control strategy step,
It is characterized in that the fuel load capacity counter circuit step includes the following contents:
(1) calculate each coal pulverizer load capacity, the load capacity of each coal pulverizer by each coal pulverizer maximum can with coal amount with
The calorific value correction coefficient of current coal pulverizer is multiplied to obtain, and the calorific value correction coefficient is the current coal pulverizer that operator is manually entered
Coal quality calorific value is converted to obtain through design coal calorific value, and the maximum of the coal pulverizer can be with coal amount by the manually or automatically shape of feeder
State determines, is current coal amount when manual mode, is the maximum load capacity of current coal pulverizer when auto state；
(2) it is added the load capacity of each coal pulverizer coal amount corresponding with fuel flow to obtain total fuel capability, then is patrolled by original
The polygronal function for collecting design is scaled fuel load capacity；
The design subsidiary engine RUNBACK control strategy step includes the following contents:
Subsidiary engine RUNBACK trigger while calculate do not trip coal pulverizer Current fuel can on-load, and in former relay protective scheme
The RUNBACK target load of design is compared, and the subsidiary engine RUNBACK target load finally exported is determined, if Current fuel
Can on-load be more than or equal to the target load of unit original logical design, subsidiary engine RUNBACK target load keeps former design value output；
If Current fuel can on-load be less than the target load of former logical design, subsidiary engine RUNBACK target load output valve is selected as working as
Preceding fuel can on-load.
The invention proposes one kind based on the dispersion modified fossil power plant auxiliary engine RUNBACK control method of calorific value, solves
Interference of the coal quality to coal pulverizer load capacity when burning different medium-heat-value coals is mixed, the coal quality that the method fully considers that every mill uses is poor
It is different, burning coal will be mixed particular by calorific value and is converted as design coal equivalent, calculates the true load capacity of each coal pulverizer, then use
The load capacity of each coal pulverizer coal amount corresponding with fuel flow is added to obtain total fuel capability, then passes through former logical design
Polygronal function is scaled fuel load capacity；New subsidiary engine RUNBACK target load is designed simultaneously and calculates control strategy, in fuel
Can on-load ability when being lower than former target load design value switching target load be Current fuel can on-load, guarantee that unit mixes burning
The major pant item load that surprisingly trips is down to the load that still can bear in the subsidiary engine of operation when low calorific value coal is run, it is ensured that current real
The stability and safety of border work unit operation.In addition, the calorific value correction coefficient in (1) step is exactly that current coal-fired calorific value removes
It is obtained with standard hot value；(2) polygronal function of the former logical design in step is existing operation function formula, is set by generating set
Counting the debugging stage determines, due to fuel quantity and unit load be not it is in a linear relationship, design the debugging stage in generating set
It can determine whether the corresponding fuel quantity polygronal function of several main loads points, actually the function composition of multistage Y=aX+b, according to listing
Several endpoint values, functional expression is calculated by the value of two endpoints respectively, such as 500MW load corresponds to how many fuel quantity, 600MW
Load corresponds to how many fuel quantity, the then Y=aX+B function meter according to determined by two endpoints of the load within the scope of two endpoints
Corresponding fuel quantity is calculated, 600MW to 700MW is another section of Y=aX+b function again, and different generating set performances is different, institute
Be with the corresponding fuel quantity of each load point of different units it is different, this is state of the art.
Detailed description of the invention
Fig. 1: fuel load capacity calculates schematic diagram in embodiment of the present invention.
Fig. 2: subsidiary engine RUNBACK target load output valve calculates schematic diagram in embodiment of the present invention.
Specific embodiment
The present invention is described further with specific embodiment for explanation with reference to the accompanying drawing.
As shown in Fig. 1~2, one kind is based on the dispersion modified fossil power plant auxiliary engine RUNBACK control method of calorific value, including combustion
Material strip loading capability counter circuit step and design subsidiary engine RUNBACK control strategy step, it is characterized in that the fuel load capacity
Counter circuit step includes the following contents:
(1) calculate each coal pulverizer load capacity, the load capacity of each coal pulverizer by each coal pulverizer maximum can with coal amount with
The calorific value correction coefficient of current coal pulverizer is multiplied to obtain, and the calorific value correction coefficient is the current coal pulverizer that operator is manually entered
Coal quality calorific value is converted to obtain through design coal calorific value, and the maximum of the coal pulverizer can be with coal amount by the manually or automatically shape of feeder
State determines, is current coal amount when manual mode, is the maximum load capacity of current coal pulverizer when auto state；
(2) it is added the load capacity of each coal pulverizer coal amount corresponding with fuel flow to obtain total fuel capability, then is patrolled by original
The polygronal function for collecting design is scaled fuel load capacity；
The design subsidiary engine RUNBACK control strategy step includes the following contents:
Subsidiary engine RUNBACK trigger while calculate do not trip coal pulverizer Current fuel can on-load, and in former relay protective scheme
The RUNBACK target load of design is compared, and the subsidiary engine RUNBACK target load finally exported is determined, if Current fuel
Can on-load be more than or equal to the target load of unit original logical design, subsidiary engine RUNBACK target load keeps former design value output；
If Current fuel can on-load be less than the target load of former logical design, subsidiary engine RUNBACK target load output valve is selected as working as
Preceding fuel can on-load.
For control method of the present invention in the unit application of somewhere 2, No. 2 units are ultra supercritical 1000MW coal burning machine
Group, the unit boiler are B&W company Ultra-supercritical Boiler, configure six coal pulverizers, and five operations one are spare；Mix burning coal
It kind is Indonesia's Import Coal, high-moisture high volatile, different batches coal calorific value mixes burning in 2800 ~ 3600kcal/kg, using a point storehouse, and 2
~ 3 coal pulverizers mix burning low calorific value coal.As shown in fig. 1, according to boiler design coal and calorific value, the separate unit of mixing burning low calorific value coal
Coal pulverizer maximum coal-supplying amount converses separate unit coal pulverizer to coal equivalent, reflects the true load capacity of low calorific value coal mill, wherein
Zhoushan coal No. 2 unit boiler design coal calorific values of electricity are 5378kcal/kg, mix the grinding belt loading capability about design for burning low calorific value coal
Between the 52% ~ 67% of coal.
When mixing burning trial operation, 2 middle layer coal pulverizers use low calorific value coal, and the coal calorific value for mixing burning is low, under the same load
Coal amount increased significantly, and need to start spare mill when unit load is higher, according to the intrinsic RUNBACK relay protective scheme of unit,
When primary air fan ,/air-introduced machine, air preheater and feed pump RUNBACK action triggers are sent, RUNBACK target load is 500MW, is jumped
3 coal pulverizers of lock, respectively two upper layers mill and a bottom mill, and five mill operations when using conventional coal, subsidiary engine RUNBACK are jumped
2, lock mills, coal amount increase so that mix burn low calorific value coal operating condition fan operation next time pressure it is larger, mix burning in low calorific value coal
The RUNBACK verification experimental verification of the primary air fan validity of the method for the present invention is scheduled between trial run period.Coal motor group AGC at present
Range of operation temporarily transfers load lower limit to 400MW before test between 50% ~ 100%, and carries out under coordinated control mode
Load change test between 400MW-500MW confirmed that unit is in the stable of the load setting under coordinated control mode
Property.
It is clapped in test by operations staff and stops a primary air fan, large-size screen monitors show primary air fan RUNBACK movement, and coal pulverizer is pressed
According to design sequence and time interval automatic trip, remains two and use low calorific value coal mill and a conventional coal mill operation, such as Fig. 1
With the fuel load capacity for calculating current operation coal pulverizer shown in Fig. 2, calculated result is obtained according to coal calorific value in test
For 447MW, being less than RUNBACK target load 500MW, RUNBACK target load final output value is 447MW, fuel, air quantity and
Water supply is rapidly decreased to target load respective value, and as the decline of main vapour pressure and pitch turn down, unit load is with the speed of 2000MW/min
The automatic load down of rate, when steady load is down to 490MW, operations staff's hand resetting RUNBACK is acted, unit RUNBACK process
In each parameter do not fluctuate widely, run primary air fan electric current, primary air pressure, master, reheat steam temperature, combustion chamber draft
Fluctuated within controlled range.
Claims (1)
1. one kind is calculated based on the dispersion modified fossil power plant auxiliary engine RUNBACK control method of calorific value, including fuel load capacity
Loop step and design subsidiary engine RUNBACK control strategy step, it is characterized in that the fuel load capacity counter circuit step packet
Include the following contents:
(1) calculate each coal pulverizer load capacity, the load capacity of each coal pulverizer by each coal pulverizer maximum can with coal amount with
The calorific value correction coefficient of current coal pulverizer is multiplied to obtain, and the calorific value correction coefficient is the current coal pulverizer that operator is manually entered
Coal quality calorific value is converted to obtain through design coal calorific value, and the maximum of the coal pulverizer can be with coal amount by the manually or automatically shape of feeder
State determines, is current coal amount when manual mode, is the maximum load capacity of current coal pulverizer when auto state；
(2) it is added the load capacity of each coal pulverizer coal amount corresponding with fuel flow to obtain total fuel capability, then is patrolled by original
The polygronal function for collecting design is scaled fuel load capacity；
The design subsidiary engine RUNBACK control strategy step includes the following contents:
Subsidiary engine RUNBACK trigger while calculate do not trip coal pulverizer Current fuel can on-load, and in former relay protective scheme
The RUNBACK target load of design is compared, and the subsidiary engine RUNBACK target load finally exported is determined, if Current fuel
Can on-load be more than or equal to the target load of unit original logical design, subsidiary engine RUNBACK target load keeps former design value output；
If Current fuel can on-load be less than the target load of former logical design, subsidiary engine RUNBACK target load output valve is selected as working as
Preceding fuel can on-load.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810705249.0A CN109062037A (en) | 2018-07-02 | 2018-07-02 | One kind is based on the dispersion modified fossil power plant auxiliary engine RUNBACK control method of calorific value |
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| CN201810705249.0A CN109062037A (en) | 2018-07-02 | 2018-07-02 | One kind is based on the dispersion modified fossil power plant auxiliary engine RUNBACK control method of calorific value |
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Cited By (2)
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| CN109718943A (en) * | 2019-01-22 | 2019-05-07 | 华润电力（海丰）有限公司 | A kind of pulverized coal preparation system control method and device |
| CN111077765A (en) * | 2019-12-17 | 2020-04-28 | 浙江浙能技术研究院有限公司 | Auxiliary machine RUNBACK protection control method for deep peak shaving working condition of thermal power generating unit |
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