CN207212500U - The system of gas turbine inlet air temperature in a kind of control cogeneration of heat and power - Google Patents
The system of gas turbine inlet air temperature in a kind of control cogeneration of heat and power Download PDFInfo
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- CN207212500U CN207212500U CN201720492447.4U CN201720492447U CN207212500U CN 207212500 U CN207212500 U CN 207212500U CN 201720492447 U CN201720492447 U CN 201720492447U CN 207212500 U CN207212500 U CN 207212500U
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- heat
- inlet air
- temperature
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- air temperature
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Abstract
The utility model discloses a kind of system for controlling gas turbine inlet air temperature in cogeneration of heat and power；Including the co-generation unit being connected with power network, gas distributing system；The intake air temperature control system being connected with co-generation unit and inlet air；Co-generation unit provides thermal source, and drives intake air temperature control system to run；Intake air temperature control system is responsible for obtaining the temperature of inlet air, and inlet air is heated or cooled.The system can realize that winter heats gas turbine inlet air, improve intake air temperature, reduce ambient humidity, and then the wet stifled and ice for solving unit gas handling system blocks up problem；Summer by the temperature under high-temperature fuel gas turbine inlet air cooling to ISO design requirements, makes gas turbine be run under the operating mode of optimum efficiency, improves the generated output and safety in operation of gas turbine.The system can effectively control gas turbine inlet air temperature, so as to improve the operating load of gas turbine and generated output, improve the security reliability of unit operation.
Description
Technical field
It the utility model is related to gas turbine inlet air in combined thermal power generation energy supply system, more particularly to a kind of control cogeneration of heat and power
The system of temperature.
Background technology
Co-generation unit mainly by gas turbine, waste heat boiler, Steam Turbine into.High temperature caused by combustion of natural gas is high
Flue gas is pressed by gas turbine power generation, the flue gas after generating enters back into waste heat boiler production high steam and delivers to steam turbine power generation,
Some vapor is extracted from steam turbine provide production heat and winter heating heat, or supply refrigeration plant system to heat user simultaneously
It is cold.
Gas turbine in co-generation unit is a kind of dynamic power machine, and it is mainly by compressor, combustion chamber and turbine
This three big part composition.In gas turbine normal work, compressor sucks air from ambient atmosphere, and it is compressed to one
The fuel in combustion chamber with penetrating is sent to after fixed pressure to mix, and is burnt as the combustion gas of high temperature.This strand of HTHP
When combustion gas flows through turbine, turbine will be expanded against and rotate work done with the superhigh speed of compressor one.Generally, combustion gas institute in turbine
The mechanical work of work, about 2/3 or so is used to consumption in the compression wasted work of air.
In co-generation unit, the temperature and humidity of inlet air have for the power of gas turbine and its combined cycle
Considerable influence.The wasted work amount of compressor is the proportional change of temperature with the air of suction, with atmospheric temperature
Rise, the density of air diminishes, and causes the mass flow for sucking the air of compressor to reduce, causes combustion gas turbine amount of work
Reduce, and the delivery temperature of combustion gas turbine has increased.Therefore, recirculated water can obtain more energy in waste heat boiler
Amount, makes greater amount of mechanical work into steam turbine, so combined cycle is relatively defeated so as to obtain more steam
It is then gentler than gas turbine to go out the degree of power reduction, and the trend that the relative efficiency of combined cycle is increased slightly on the contrary.
Conversely, when atmospheric temperature declines, the degree of the relative power output increase of combined cycle is then fewer than gas turbine, and combines
The relative efficiency of circulation has the trend being slightly reduced on the contrary.
At present, the performance parameter of gas turbine obtains at iso conditions, and northern China plant gas combustion engine air inlet
System can not well adapt to local climate environmental condition sometimes, especially in the winter time, gas handling system generally occur it is wet stifled and
Ice blocks up phenomenon, and unit has to reduce load operation under the extreme weather conditions such as sleet haze so that compressor itself is born
Lotus changes, and causes mechanical efficiency to change, system operation off-design best efficiency point, even occurs that chaser shows when serious
As；And in summer, inlet air temperature height can cause the reduction of combustion engine efficiency, and this leverages the security and hair of power plant's operation
Electrical power.Therefore the stable performance to whole recycle unit of control gas turbine intake air temperature reaches optimal and system stabilization
Run it is particularly significant, can also safe operation provides important leverage in the winter time and under summer various weather conditions for plant gas.
The content of the invention
The shortcomings that the purpose of this utility model is to overcome above-mentioned prior art and deficiency, there is provided one kind control cogeneration of heat and power
The system of middle gas turbine inlet air temperature.When solving above-mentioned atmospheric temperature deviation ISO design requirements, the density of air becomes
Change, that is, the mass flow of air for sucking compressor changes, and during the extreme weather such as winter sleet, intake air temperature is low, air inlet
There is phenomena such as wet stifled and ice is stifled in system, it has to reduces unit load, or even chaser phenomenon occurs, causes mechanical efficiency
Change, system operation off-design best efficiency point；When summer intake air temperature is high, the problem of combustion engine efficiency is low；The utility model
Co-generation unit can be made to be run under optimum condition.
The utility model is achieved through the following technical solutions：
The system of gas turbine inlet air temperature in a kind of control cogeneration of heat and power, including：
The co-generation unit A1 being connected with power network, gas distributing system；
The intake air temperature control system A2 being connected with co-generation unit A1 and inlet air；
The co-generation unit A1 provides thermal source, and drives intake air temperature control system A2 to run；
The intake air temperature control system A2 is responsible for obtaining the temperature of inlet air, and inlet air is heated or cold
But.
The intake air temperature control system A2 includes such as lower component：
Temperature controller a2；
Heat exchanger a3；
Air flow valve V1；
Water supply flow valve V2；
Residual heat type lithium bromide Double-working-condition unit a1；
Recirculated water in the heat exchanger a3 enters residual heat type lithium bromide Double-working-condition unit a1 by a pipeline and realizes heat exchange
Afterwards, then by being provided with water supply flow valve V2Another pipeline return to heat exchanger a3；
Temperature controller a2 temperature sensor is arranged on heat exchanger (a3) export pipeline, is changed for obtaining to enter
The temperature data of hot device a3 outlet airs；Temperature controller a2 control terminal connection water supply flow valve V2, for controlling the stream that supplies water
Measure valve V2 aperture；
After temperature sensor obtains the temperature data of inlet air, temperature controller a2 is sent to, by being built in temperature control
Signal amplification module in device a2 processed is amplified to it, and after A/D conversions, is realized by control module to water supply flow valve V2
Valve opening be controlled, by residual heat type lithium bromide Double-working-condition unit a1 provide heat or cold water into heat exchanger a3 it is empty with import
Gas is exchanged heat, and inlet air is heated or cooled so as to realize.
The co-generation unit A1 includes such as lower component：
Gas turbine；
Waste heat boiler；
Sucking condensing turbine；
Realize that the air of heat exchange enters gas turbine in heat exchanger a3, flue gas enters waste heat boiler as caused by turbine,
Recirculated water in waste heat boiler is entered sucking condensing turbine after the flue gas；
The residual heat type lithium bromide Double-working-condition unit a1 is flue gas type lithium bromide Double-working-condition unit and/or steam type lithium bromide
Double-working-condition unit；
When using flue gas type lithium bromide Double-working-condition unit, it drives flue gas to come from waste heat boiler；
When using steam type lithium bromide Double-working-condition unit, it drives steam to come from sucking condensing turbine.
For one kind using gas turbine inlet air temperature methods in waste heat control combined thermal power generation energy supply system, it includes following two
Rate-determining steps：
Rate-determining steps during winter
By controlling air flow valve V1Valve opening, obtain stable air mass flow F1；
Temperature sensor obtains corresponding temperature signal t in air1, then the signal by being built in temperature controller a2 puts
Big module is amplified to it, and passes to single-chip microcomputer after A/D conversions；
Set by single-chip microcomputer or given one will not make gas turbine occur the stifled phenomenon of wet stifled and ice in the course of the work
Temperature t2Afterwards, the series of parameters properties such as the enthalpy of air, density, mass flow are obtained and air is heated to t2Required
Heat Q, then obtain now water supply flow valve V2Great valve opening is needed to provide corresponding heat；Finally by temperature
Control module built in controller a2 is realized to water supply flow valve V2Valve opening be controlled, by residual heat type lithium bromide duplex
Condition unit provides hot water and exchanged heat into heat exchanger a3 with inlet air；
Work as t1More than the t of setting2When, then the control module built in temperature controller a2 reduces water supply flow valve V2Valve
Aperture, and then reduce the flow F of hot water2；Work as t1Less than the t of setting2When, then the control module built in temperature controller a2 performs
Increase water supply flow valve V2Valve opening, and then increase hot water flow F2；
Rate-determining steps during summer
By controlling air flow valve V1Valve opening, obtain stable air mass flow F1；
Temperature sensor obtains corresponding temperature signal t in air1, then the signal by being built in temperature controller a2 puts
Big module is amplified to it, and passes to single-chip microcomputer after A/D conversions；
The temperature t under the conditions of an ISO is set or given by single-chip microcomputer2Afterwards, the enthalpy of air, density, quality stream are obtained
Amount etc. and cools air to t at series of parameters property2Required cold Q, then obtain now water supply flow valve V2Need much
Valve opening corresponding cold could be provided；Realized finally by the control module built in temperature controller a2 to water supply flow
Valve V2Valve opening be controlled, by residual heat type lithium bromide Double-working-condition unit provide cold water into heat exchanger a3 with inlet air
Heat exchange；
Work as t1More than the t of setting2When, then the control module built in temperature controller a2 increases water supply flow valve V2Valve
Aperture, and then increase the flow F of cold water2；
Work as t1Less than the t of setting2When, then the control module built in temperature controller a2 reduces water supply flow valve V2Valve
Aperture, and then reduce the flow F of cold water2。
The utility model is had the following advantages and effect relative to prior art：
Analyzed in terms of security, the utility model can solve that winter atmospheric temperature is relatively low or the extreme weather such as sleet haze
In the case of, there is situations such as wet stifled and ice is stifled in gas handling system, and gas turbine unit is had to reduce load operation or even is drawn
The chaser problem risen.Meanwhile summer makes gas turbine unit be run under design conditions, can effectively extend unit uses the longevity
Life.
Analyzed in terms of generated output, the utility model co-generation unit by low-quality heat energy recycle in refrigeration,
Cooling gas turbine inlet air temperature, effective utilization of the energy was both realized, it is possibility to have the raising gas turbine of effect is done
Function power.
Brief description of the drawings
Fig. 1 is the system structure diagram that the utility model controls gas turbine inlet air temperature in cogeneration of heat and power.
When the higher inlet air temperature of Fig. 2 expressions and corresponding humidity decline temperature are arrived under ISO temperature conditionss, cogeneration of heat and power system
Uniting A1 institutes can increased generated output.
Embodiment
The utility model is more specifically described in detail with reference to Fig. 1, Fig. 2 and specific embodiment.
By taking northern somewhere as an example, it is assumed that this area's summer mean temperature is 37.8 DEG C, and mean winter temperature is -1 DEG C.
In co-generation unit A1, gas turbine is 255.6MW natural gas power unit, and its important technological parameters is as shown in table 1；
The important technological parameters of waste heat boiler are as shown in table 2；Steam turbine be 141MW generating set, its important technological parameters such as institute of table 3
Show.
The gas turbine unit important technological parameters of table 1
The waste heat boiler important technological parameters of table 2
The steam-turbine unit important technological parameters of table 3
Residual heat type lithium bromide Double-working-condition unit a1 from 2 steam type water chiller-heater units (maximum cooling capacity 18.6MW, most
Great heating capacity is 15.4MW), its important technological parameters is as shown in table 4.
The steam type water chiller-heater unit important technological parameters of table 4
As shown in figure 1,512.9m3/ s air enters in compressor after heat exchanger a3 is heated (cooling)
Row compression, obtain HTHP air enter combustion chamber in 20.0Nm3/ s natural gas is burnt, caused by after burning
High temperature and high pressure flue gas promotes turbine rotation work done at a high speed, and a part is used for driving compressor, a part of then surfed the Net for generating electricity.Make
600 DEG C or so of high-temperature flue gas after work(cools by waste heat boiler heat cycles water, and the flue gas after cooling can be used for driving
Residual heat type lithium bromide Double-working-condition unit a1.And it is changed into high-temperature high-pressure steam after circulating water heating, water vapour pushing turbine again
Work done, which generates electricity, surfs the Net or carries out to extract some vapor to heat user offer production heat and winter heating heat.
Some vapor is extracted from waste heat boiler to be input in residual heat type lithium bromide Double-working-condition unit a1 steam type unit,
Drive train is run arrives required temperature by the temperature heating (cooling) of inlet air.
The residual heat type lithium bromide Double-working-condition unit, flue gas formula unit also can be selected, driving heat source now is then waste heat
The flue gas of boiler.
, can be with inlet air without heating (drop in order to preferably embody the security and generated output in implementation process
Temperature) situation contrasted.
1) winter rate-determining steps：
When temperature is less than the temperature under the conditions of ISO, the mass flow increase of inlet air, co-generation unit does function
Power increases.But temperature is too low or even when under extreme weather conditions, it is stifled and wet stifled that ice easily occurs in gas turbine unit
Situation, therefore will to inlet air carry out heat temperature raising.In this patent calculates case, to prevent inlet air from ice can occur
It is stifled and wet stifled, 5 DEG C are heated to it.
It is -1 DEG C that temperature controller a2 measures inlet air temperature first, humidity 78.0%, and obtains air now
Density and enthalpy, corresponding mass flow can be calculated for 660.5kg/s and required confession when being heated to 5 DEG C by computer
The thermic load given is 3.90MW.Because steam type unit a1 is in the situation of specified heating capacity all the time, and inlet air is heated to 5
Heat needed for DEG C only need to be by controlling hot water supply valve V2Corresponding hot water flow is obtained to obtain with heat exchanger heat exchange.Last temperature
Degree controller a2 sends the hot water supply valve V of Signal Regulation again2Aperture for 53.1% come meet heat demand (it is assumed that heat exchanger imitate
95%) rate is.Specified heating capacity according to steam type unit a1 is 7733kW and heating COP is 2.30, can be calculated required take out
The steam flow taken is 1.59kg/s.(when wherein, inlet air temperature is less than -6.9 DEG C, i.e., required thermic load is higher than 7733kW
When, it is necessary to use two steam type units simultaneously)
When the expression inlet temperature of table 5 is -1 DEG C, co-generation unit A1 is used and the contrast situation without using the system.
The co-generation unit of table 5 uses and the contrast without using the system
By comparing calculation, extract some vapor and inlet air is heated, although generated output can subtract
It is few, but unit heavy-duty service all the time under extreme weather conditions can be effectively ensured, chaser phenomenon, security will not be caused
It is good.
2) during summer
Temperature controller a2 measures that inlet air temperature is 37.8 DEG C and humidity is 15.6% first, and obtains sky now
Air tightness and enthalpy, corresponding mass flow can be calculated as 577.8kg/s by computer and cool to ISO temperature when institute
The refrigeration duty for needing to supply is 14.29MW.Because steam type unit a1 is in the situation of rated cooling capacity, and inlet air all the time
Being cooled to the cold needed for ISO temperature only need to be by controlling cold water supply valve V2Corresponding cold water flow is obtained to exchange heat with heat exchanger
Obtain.End temperature controller a2 sends the cold water supply valve V of one unit of Signal Regulation again2Aperture be 100%, Ling Yitai
Meet heat demand (it is assumed that heat exchanger efficiency is 95%) for 56.5%.Rated cooling capacity according to steam type unit a1 is
9300kW and refrigeration COP is 1.40, and the steam flow that can be calculated required extraction is 6.34kg/s, now needs to use two machines
Group.(wherein, inlet air temperature at 15~29.5 DEG C, it is necessary to open a steam type unit, the steam flow of required extraction
For 3.17kg/s；Inlet air temperature is at 29.5~44 DEG C, it is necessary to open two steam type units)
Table 6 represent inlet temperature be 37.8 DEG C when, co-generation unit A1 use with the contrast situation without using the system,
Fig. 2 then represents higher inlet air temperature and when corresponding humidity declines temperature and arrived under ISO temperature conditionss, co-generation unit A1 institutes
Can increased generated output.
The co-generation unit of table 6 uses and the contrast without using the system
By comparing calculation, extract a small amount of steam and inlet air is cooled down, both gas turbine can be allowed to set
Run under meter operating mode, the service life of unit can be extended to a certain extent, while generated output can be increased again, so
It is highly significant that summer, which carries out cooling to the inlet air of high temperature,.
3) transition period
Except during summer described above and winter extreme condition under, under remaining environment temperature as 5-15 DEG C when, can not be to entering
The temperature of mouth air is handled, and now the stifled and wet stifled feelings for waiting influence unit normal operation of ice will not both occur for inlet air
Condition, compared to can also possess higher generated output under ISO temperature conditionss.
As described above, it can preferably realize the utility model.
Embodiment of the present utility model is simultaneously not restricted to the described embodiments, and other are any without departing from of the present utility model
Spirit Essence with made under principle change, modification, replacement, combine, simplification, should be equivalent substitute mode, be included in
Within the scope of protection of the utility model.
Claims (2)
- A kind of 1. system for controlling gas turbine inlet air temperature in cogeneration of heat and power, it is characterised in that including：The co-generation unit (A1) being connected with power network, gas distributing system；The intake air temperature control system (A2) being connected with co-generation unit (A1) and inlet air；The co-generation unit (A1) provides thermal source, and drives intake air temperature control system (A2) to run；The intake air temperature control system (A2) is responsible for obtaining the temperature of inlet air, and inlet air is heated or cold But；The intake air temperature control system (A2) includes such as lower component：Temperature controller (a2)；Heat exchanger (a3)；Air flow valve (V1)；Water supply flow valve (V2)；Residual heat type lithium bromide Double-working-condition unit (a1)；Recirculated water in the heat exchanger (a3) enters residual heat type lithium bromide Double-working-condition unit (a1) by a pipeline and realizes heat exchange Afterwards, then by being provided with water supply flow valve V2Another pipeline return heat exchanger (a3)；The temperature sensor of the temperature controller (a2) is arranged on heat exchanger (a3) export pipeline, enters heat exchange for obtaining The temperature data of device (a3) outlet air；The control terminal connection water supply flow valve (V of temperature controller (a2)2), supplied for controlling Water flow valve (V2) aperture；After temperature sensor obtains the temperature data of inlet air, temperature controller (a2) is sent to, by being built in temperature control Signal amplification module in device (a2) is amplified to it, and after A/D conversions, is realized by control module to water supply flow valve (V2) valve opening be controlled, by residual heat type lithium bromide Double-working-condition unit (a1) provide heat or cold water into heat exchanger (a3) Exchange heat with inlet air, inlet air is heated or cooled so as to realize.
- 2. the system of gas turbine inlet air temperature in cogeneration of heat and power is controlled according to claim 1, it is characterised in that the heat Cogeneration system (A1) includes such as lower component：Gas turbine；Waste heat boiler；Sucking condensing turbine；Realize that the air of heat exchange enters gas turbine in heat exchanger (a3), the flue gas as caused by turbine enters waste heat boiler, remaining Recirculated water in heat boiler is entered sucking condensing turbine after the flue gas；The residual heat type lithium bromide Double-working-condition unit (a1) is that flue gas type lithium bromide Double-working-condition unit and/or steam type lithium bromide are double Operating mode unit；When using flue gas type lithium bromide Double-working-condition unit, it drives flue gas to come from waste heat boiler；When using steam type lithium bromide Double-working-condition unit, it drives steam to come from sucking condensing turbine.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720492447.4U CN207212500U (en) | 2017-05-05 | 2017-05-05 | The system of gas turbine inlet air temperature in a kind of control cogeneration of heat and power |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720492447.4U CN207212500U (en) | 2017-05-05 | 2017-05-05 | The system of gas turbine inlet air temperature in a kind of control cogeneration of heat and power |
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| Publication Number | Publication Date |
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| CN207212500U true CN207212500U (en) | 2018-04-10 |
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ID=61810988
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201720492447.4U Expired - Fee Related CN207212500U (en) | 2017-05-05 | 2017-05-05 | The system of gas turbine inlet air temperature in a kind of control cogeneration of heat and power |
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| CN (1) | CN207212500U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107420204A (en) * | 2017-05-05 | 2017-12-01 | 华南理工大学 | The system and method for gas turbine inlet air temperature in a kind of control cogeneration of heat and power |
| CN110986067A (en) * | 2019-12-06 | 2020-04-10 | 上海电气燃气轮机有限公司 | Blow pipe system for combined cycle power plant boiler and operation method thereof |
-
2017
- 2017-05-05 CN CN201720492447.4U patent/CN207212500U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107420204A (en) * | 2017-05-05 | 2017-12-01 | 华南理工大学 | The system and method for gas turbine inlet air temperature in a kind of control cogeneration of heat and power |
| CN107420204B (en) * | 2017-05-05 | 2023-02-14 | 华南理工大学 | System and method for controlling gas turbine inlet air temperature in combined heat and power generation |
| CN110986067A (en) * | 2019-12-06 | 2020-04-10 | 上海电气燃气轮机有限公司 | Blow pipe system for combined cycle power plant boiler and operation method thereof |
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| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
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Granted publication date: 20180410 Termination date: 20190505 |