CN106948890B - A kind of method of warming up suitable for high pressure combined launch Turbo-generator Set - Google Patents

A kind of method of warming up suitable for high pressure combined launch Turbo-generator Set Download PDF

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Publication number
CN106948890B
CN106948890B CN201710227295.XA CN201710227295A CN106948890B CN 106948890 B CN106948890 B CN 106948890B CN 201710227295 A CN201710227295 A CN 201710227295A CN 106948890 B CN106948890 B CN 106948890B
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warming
turbo
high pressure
generator set
deviation
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CN106948890A (en
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徐章福
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Electric Power Research Institute of Guizhou Power Grid Co Ltd
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Electric Power Research Institute of Guizhou Power Grid Co Ltd
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01KSTEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K13/00General layout or general methods of operation of complete plants
    • F01K13/02Controlling, e.g. stopping or starting
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01KSTEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K7/00Steam engine plants characterised by the use of specific types of engine; Plants or engines characterised by their use of special steam systems, cycles or processes; Control means specially adapted for such systems, cycles or processes; Use of withdrawn or exhaust steam for feed-water heating
    • F01K7/16Steam engine plants characterised by the use of specific types of engine; Plants or engines characterised by their use of special steam systems, cycles or processes; Control means specially adapted for such systems, cycles or processes; Use of withdrawn or exhaust steam for feed-water heating the engines being only of turbine type
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P80/00Climate change mitigation technologies for sector-wide applications
    • Y02P80/10Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier
    • Y02P80/15On-site combined power, heat or cool generation or distribution, e.g. combined heat and power [CHP] supply

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Turbines (AREA)

Abstract

The invention discloses a kind of method of warming up suitable for high pressure combined launch Turbo-generator Set, the present invention is on the basis of unit original revolution speed control system, increase the logic of a set of automatic warming, by to Turbo-generator Set deh control system mesohigh stop valve bit function g (Δ x) and reheat control valve bit function h (the real-time amendment of Δ x), realize the overall process automatic warming of senior school biology unit, that there are warm-up periods is long for the Turbo-generator Set for solving using high pressure combined launch, the insufficient problem of warming-up, it also can solve existing reduction parameter starting warming-up technology while energy-saving and emission-reduction simultaneously and run bring security risk to unit, it can overcome the shortcomings of currently available technology.

Description

A kind of method of warming up suitable for high pressure combined launch Turbo-generator Set
Technical field
The invention belongs to thermal power generating technology fields, are related to a kind of adaptable, high degree of automation, can shorten senior middle school The method for pressing the Turbo-generator Set warm-up period and warming-up effect of combined launch.
Background technique
Basically, steam turbine warming-up effect and the throttle flow of each cylinder body have relationship.It is grid-connected in unit starting warming-up Before, cylinder body throttle flow is only related with revolving speed, and warming-up is that (general Turbo-generator Set warming-up revolving speed divides low speed in a certain determining revolving speed Warming-up, medium-speed warming and high speed warming-up) under complete, if energy needed for unit is certain in the case that warming-up steam parameter is certain, I.e. throttle flow is certain, therefore how each cylinder throttle flow of coordinated allocation becomes key.Existing Turbo-generator Set warming-up technology It is main that warming-up is carried out using reduction warming-up parameter mode, that is, reduce the modes such as master, reheated steam parameter, unit vacuum.Existing skill Art, which has the following deficiencies:, reduces warming-up parameter, and the decline of energy entrained by steam, middle pressure is adjusted in the case that warming-up revolving speed is constant Valve can not turn off greatly to increase throttle flow, until high pressure main stop valve can be just turned on when generating unit speed cannot maintain, this is a kind of More passively adjustment mode.Although the method for drop parameter can make unit starting warming-up obtain good effect, do not consider to drop The unfavorable aspect of other equipment after low parameter.(1) do not consider to reduce (providing for unit to boiler after main, reheated steam parameter Steam) it influences.Boiler combustion load, low load combustion mode will certainly be reduced while steam turbine starting warming-up reduces parameter Lower boiler (especially supercritical once-through boiler) is easy to happen uneven burning, thermal deviation accumulation, back-end surfaces and superheater Overtemperature of tube wall, it is serious when even the problems such as putting out a fire, while reducing and leading, after reheated steam pressure, be easy to cause boiler hydrodynamic(al) Power is unstable, and too low main vapour pressure makes the mass velocity not being able to maintain in water-cooling wall water-cooling wall film boiling occurs, and leads Cause booster.(2) vacuum reduces excessive in unit starting warming-up process, and heat send out thermogenetic in cylinder internal cause air blast can cause metal to surpass Temperature, while being unfavorable for controlling the upper and lower temperature difference of the cylinder of unit, it will lead to rubbing between blade damage or steam turbine sound component when serious It wipes, so that turbine component be caused seriously to damage.
Summary of the invention
The present invention is to increase the logic of a set of automatic warming, by right on the basis of unit original revolution speed control system ((Δ x's) is real-time by Δ x) and reheat control valve bit function h by Turbo-generator Set deh control system mesohigh stop valve bit function g The overall process automatic warming of senior school biology unit is realized in amendment.It solves to send out using the steamer of high pressure combined launch Motor group there are warm-up periods long, the insufficient problem of warming-up also can solve existing reduction parameter starting while energy-saving and emission-reduction Warming-up technology runs bring security risk to unit.
A kind of technical solution provided by the invention are as follows: the side of fast and stable revolving speed after the removal of load for Turbo-generator Set Method, comprising the following steps:
The first step, after Turbo-generator Set reaches warming-up revolving speed, DEH revolving speed control according to setting speed ω1With reality Rotational speed omega2Deviation Δ ω, Turbo-generator Set actual speed value and setting speed value base are controlled by PID controller A always This is consistent;
Second step, operations staff put into warm cylinder mode, select the cylinder body for needing preferentially to warm up, and set heating rate t1Afterwards, DEH Temp measuring system meeting real-time detection center housing temperature and the practical temperature rise rate t for calculating cylinder body2, set heating rate t1With practical heating speed Rate t2Heating rate deviation Δ t is exported more afterwards1
Third step, deviation Δ t1Δ t is exported after height limits module, after deviation Δ t is then inputted PID controller B, The output bias value Δ x after PID controller B calculating2With Δ x3
4th step, deviation Δ x2With Δ x3It is superimposed upon high pressure main stop valve bit function and reheat control valve bit function mould respectively On block, the on or off of main inlet throttle-stop valve and middle pitch is controlled.
The mathematical computations expression formula of the Δ ω are as follows:
Δ ω=ω12
In formula: revolving speed deviation Δ ω, setting speed ω1, with actual speed ω2
The heating rate deviation Δ t1Mathematic(al) representation are as follows:
Δ t=t1-t2
In formula: setting heating rate t1, practical heating rate t2, heating rate deviation Δ t1
The deviation Δ x2With Δ x3Mathematical relationship expression formula and valve correspond to aperture relationship are as follows:
In formula: Δ x1For the comprehensive valve bit instruction that PID controller 1 exports, corresponding number is 0%~100%;Δ x is Δ x1 Valve bit instruction after rate limit, corresponding number are 0%~100%;Δx2、Δx3For the amendment valve of PID controller B output Bit instruction, corresponding number are 0%~100%;g(Δx+Δx2) be and Δ x+ Δ x2Relevant linear function, the corresponding main vapour of high pressure The full pass (0%) of door and standard-sized sheet (100%);h(Δx+Δx3) be and Δ x+ Δ x3Relevant linear function, it is corresponding in press and adjust The full pass (0%) of door and standard-sized sheet (100%).
The cylinder body includes high pressure cylinder and intermediate pressure cylinder.
Using technical solution of the present invention, in high pressure main stop valve bit function g (Δ x) and reheat control valve bit function h (Δ x) A set of logic in parallel before module (for confirming the investment of warm cylinder mode, and selects preferential warm anticyclone cylinder also by warm cylinder selecting module Intermediate pressure cylinder, the module put into whether decide whether this set logic works), cylinder temperature rise rate setting module t1(for setting Desired warm cylinder temperature rise rate), cylinder temperature temperature rise rate computing module t2(for calculating the actual cylinder temperature rise rate of current unit), high limit Module (for judge current cylinder temperature rise rate whether be more than setting limits value), PID controller B (receive input value and by one Output valve is provided after fixed regular operation) composition.
Its warming-up logical action principle are as follows: after Turbo-generator Set reaches warming-up revolving speed, DEH revolving speed is controlled according to setting Rotational speed omega1With actual speed ω2Deviation Δ ω situation (positive value open the door, bear to close the door), steamer is controlled by controller A always Generating set actual speed value is worth almost the same with setting speed.When operations staff puts into warm cylinder mode, selection needs preferential warm Cylinder body (high pressure cylinder or intermediate pressure cylinder), set desired setting heating rate t1Afterwards, DEH temp measuring system can measure cylinder body temperature in real time Spend and calculate the practical temperature rise rate t of cylinder body2, setting value rear output bias value Δ t compared with actual value1, Δ t1After height limits module Δ t is exported, Δ t exports Δ x after inputting PID controller B2、Δx3, Δ x2、Δx3Be superimposed upon respectively high pressure main stop valve bit function and In reheat control valve bit function module, the on or off of main inlet throttle-stop valve and middle pitch is determined.
Compared with the prior art, 2~3 times faster than prior art method of warming up of method of warming up of the invention, by manufacturer's recommended The medium-speed warming time 150 minutes, compared with prior art, the present invention saving between 150 minutes to 300 minutes time, take Between value 225 minutes, be 3.75 hours.Boiler can put into 6~8 oil guns in red switch warming-up process, and every Oil Gun exists 1.0t/h or so, with the minimum output calculation of boiler oil gun, the present invention can save during each cold start of the type unit Fuel oil 6t/h × 3.75h=22.5t, fuel cost 22.5t × 0.8 (Wan Yuan)/t=18 (Wan Yuan).It is designed by producer, the life-cycle The unit can be cold start 300 times in range, and 48,000,000 yuan can be saved for every unit by converting.The whole nation is combined using high pressure opens Motivation group accounts for the half of domestic whole installed capacitys or more, therefore the Technique Popularizing has a extensive future.
Detailed description of the invention
Fig. 1 is the revolution speed control system schematic illustration that the present invention is used for warming-up;
Attached drawing 2 is revolution speed control system schematic illustration;
Attached drawing 3: for turbogenerator thermal system schematic diagram;
Fig. 4 is the high pressure cylinder parameter before prior art warming-up starts;
Fig. 5 is the high pressure cylinder parameter before prior art warming-up terminates;
Fig. 6 is the high pressure cylinder parameter before warming-up of the present invention starts;
Fig. 7 is the high pressure cylinder parameter before warming-up of the present invention terminates.
Specific embodiment
The preferred implementation case that the invention will now be described in detail with reference to the accompanying drawings.
The 660MW supercritical turbine generator group that certain factory is produced by Harbin steam turbine, model N660-24.2/566/ 566: using senior school biology mode.The prior art mainly increases each cylinder to reduce unit starting warming-up parameter Throttle flow, especially to reduce intermediate pressure cylinder steam inlet condition, when intermediate pressure cylinder cannot maintain unit warming-up revolving speed, the height of high pressure cylinder Pressure main inlet throttle-stop valve just can be opened gradually, to achieve the purpose that warming-up, whether high pressure cylinder is sufficiently Turbo-generator Set warming-up into vapour Key.The present invention using high, intermediate pressure cylinder sharing of load ratio is actively changed, can effectively control each cylinder into vapour opportunity and Throttle flow, using flexible.By taking warm anticyclone cylinder as an example: the temperature rise after implementing by the warming-up curve under the prior art and by this patent is bent Line is as shown in attached drawing 4,5,6,7:
2 present invention of table and the prior art are to high pressure cylinder warming-up Contrast on effect
From upper table 2: (1) method for pressing existing reduction starting warming-up parameter, unit warming-up 17 minutes 7 hours, high pressure Vapor (steam) temperature goes up 265 DEG C from 112 DEG C at governing stage in cylinder;0.35 DEG C/min of average temperature rising rate;Governing stage gold in high pressure cylinder Belong to temperature to go up from 110 DEG C to 277 DEG C, 0.38 DEG C/min of average temperature rising rate
(2) press the invention patent method: unit warming-up 4 minutes 2 hours, in high pressure cylinder at governing stage vapor (steam) temperature from 187 DEG C go up to 301 DEG C, 0.92 DEG C/min of average temperature rising rate;Governing stage metal temperature goes up from 148 DEG C to 308 in high pressure cylinder DEG C, 1.29 DEG C/min of average temperature rising rate
(3) 2~3 times faster than prior art method of warming up of method of warming up of the invention, by manufacturer's recommended medium-speed warming when Between 150 minutes, compared with prior art, the present invention save 150 minutes to 300 minutes time between, take median 225 minutes, It is 3.75 hours.Boiler can put into 6~8 oil guns in red switch warming-up process, and every Oil Gun is in 1.0t/h or so, with pot The minimum output calculation of furnace oil rifle, the present invention can saving fuel oil 6t/h × 3.75h during each cold start of the type unit =22.5t, fuel cost 22.5t × 0.8 (Wan Yuan)/t=18 (Wan Yuan).It is designed by producer, the unit can in alllife range Cold start 300 times, 48,000,000 yuan can be saved for every unit by converting.The whole nation accounts for whole dresses using high pressure combined launch unit More than the half of machine capacity, therefore the Technique Popularizing has a extensive future.

Claims (4)

1. a kind of method of warming up suitable for high pressure combined launch Turbo-generator Set, it is characterised in that: the following steps are included:
The first step, after Turbo-generator Set reaches warming-up revolving speed, DEH revolving speed control according to setting speed ω1With actual speed ω2Deviation Δ ω, it is consistent with setting speed value that Turbo-generator Set actual speed value is controlled by PID controller A always;
Second step, operations staff put into warm cylinder mode, select the cylinder body for needing preferentially to warm up, and set heating rate t1Afterwards, DEH thermometric System meeting real-time detection center housing temperature and the practical temperature rise rate t for calculating cylinder body2, set heating rate t1With practical heating rate t2 Heating rate deviation Δ t is exported more afterwards1
Third step, deviation Δ t1Δ t is exported after height limits module, deviation Δ t inputs PID controller B, through PID controller B Output bias value Δ x after calculating2With Δ x3
4th step, deviation Δ x2With Δ x3It is superimposed upon in high pressure main stop valve bit function and reheat control valve bit function module respectively, Control the on or off of main inlet throttle-stop valve and middle pitch;
Deviation Δ x, Δ x2With Δ x3Mathematical relationship expression formula and valve correspond to aperture relationship are as follows:
In formula: Δ x1For the comprehensive valve bit instruction of PID controller A output, corresponding number is 0%~100%;Δ x is Δ x1Through speed Valve bit instruction after rate limitation, corresponding number are 0%~100%;Δx2、Δx3Amendment valve position for PID controller B output refers to It enables, corresponding number is 0%~100%;g(Δx+Δx2) be and Δ x+ Δ x2Relevant linear function, corresponding high-pressure main throttle valve It is complete to close (0%) and standard-sized sheet (100%);h(Δx+Δx3) be and Δ x+ Δ x3Relevant linear function, it is corresponding in pressure adjust door It is complete to close (0%) and standard-sized sheet (100%).
2. a kind of method of warming up suitable for high pressure combined launch Turbo-generator Set according to claim 1, special Sign is: the mathematical computations expression formula of the Δ ω are as follows:
Δ ω=ω12
In formula: revolving speed deviation Δ ω, setting speed ω1, with actual speed ω2
3. a kind of method of warming up suitable for high pressure combined launch Turbo-generator Set according to claim 1,
It is characterized by: the heating rate deviation Δ t1Mathematic(al) representation are as follows:
Δ t=t1-t2
In formula: setting heating rate t1, practical heating rate t2, heating rate deviation Δ t1
4. a kind of method of warming up suitable for high pressure combined launch Turbo-generator Set according to claim 1, special Sign is: the cylinder body includes high pressure cylinder and intermediate pressure cylinder.
CN201710227295.XA 2017-04-10 2017-04-10 A kind of method of warming up suitable for high pressure combined launch Turbo-generator Set Active CN106948890B (en)

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CN109597301B (en) * 2017-09-30 2021-11-16 上海梅山钢铁股份有限公司 Main steam temperature optimization control method for coke dry quenching waste heat boiler
CN110131002B (en) * 2018-02-09 2021-08-06 上海明华电力科技有限公司 High and medium pressure cylinder combined starting control method for subcritical unit based on environmental protection target
CN109356675B (en) * 2018-12-13 2021-10-22 浙江医药高等专科学校 Automatic start control method of feed pump steam turbine
CN111706406B (en) * 2020-06-15 2022-12-06 华能罗源发电有限责任公司 A fast and medium speed warm-up control system
CN116816458A (en) * 2023-02-03 2023-09-29 华电电力科学研究院有限公司 Method for controlling hot start of turbine and method and system for controlling turbine parameters

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Inventor after: Xu Zhangfu

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