The content of the invention
It is an object of the present invention to provide a kind of generating set, available for a variety of thermoelectric conversion systems, realizes that generating set is efficientThe operation of wide scope, while realize efficiently quick start.
The present invention solves technical problem and adopted the following technical scheme that：A kind of generating set, it includes Systems of Centrifugal Compressor Unit, whirlpoolTake turns unit and generator；
The output shaft of the turbine set is connected with generator drive gear；
The output shaft of the turbine set and the gear wheel of the Systems of Centrifugal Compressor Unit are connected；
The Systems of Centrifugal Compressor Unit is connected with the turbine set by pipeline, and the working medium that the turbine set is discharged is addedAfter pressure, turbine set is re-fed into by regenerator and high temperature heater (HTH), to drive the turbine set to rotate.
Optionally, the Systems of Centrifugal Compressor Unit includes a driving gear shaft and multiple driven gear shafts, the driving toothWheel shaft and driven gear shaft are parallel to each other；Gear wheel is installed on the driving gear shaft, is provided with the driven gear shaftLittle gear, the gear wheel and pinion fits, so as to form step-up drive between driving gear shaft and driven gear shaft；InstituteThe both ends for stating driven gear shaft are connected with centrifugal compressor stage.
Optionally, the quantity of the driven gear shaft is 2, including the first driven gear shaft and the second driven gear shaft；The Systems of Centrifugal Compressor Unit includes main compressor and recompression machine；The main compressor and recompression machine are two-stage compressor,The two-stage centrifugal impeller of the main compressor is connected with the both ends of the first driven gear shaft respectively, and the two of the recompression machineLevel centrifugal impeller is connected with the both ends of the second driven gear shaft respectively；Or the two-stage centrifugal impeller of the main compressorBe connected respectively with the first driven gear shaft and the second driven gear shaft, the two-stage centrifugal impeller of the recompression machine respectively withFirst driven gear shaft and the drive connection of the second driven gear shaft.
Optionally, the air inlet of the main compressor first order connects with the exhaust outlet of turbine set, the main compressorThe exhaust outlet of the first order connects with the air inlet of the main compressor second level, the exhaust outlet and gas of the main compressor second levelThe low-pressure inlet connection of body injector；The air inlet of the recompression machine first order connects with the exhaust outlet of turbine set, describedThe exhaust outlet of the recompression machine first order connects with the air inlet of the recompression machine second level, the exhaust outlet of the recompression machine second levelConnected with the high pressure entry of gas ejector, the exhaust outlet of the gas ejector is entered by high temperature heater (HTH) and turbine setGas port connects.
Optionally, the generating set also includes high temperature regenerator, cryogenic regenerator and cooler；The gas ejectorExhaust outlet connected by high temperature regenerator and high temperature heater (HTH) with the air inlet of turbine set；The exhaust outlet of the turbine setConnected respectively by high temperature regenerator, cryogenic regenerator and cooler with the air inlet of the main compressor first order；And instituteThe exhaust outlet of turbine set is stated respectively by high temperature regenerator and cryogenic regenerator and the air inlet of the recompression machine first orderConnection；And the exhaust outlet of the main compressor first order is connected by cryogenic regenerator with the low-pressure inlet of gas ejector.
The present invention has the advantages that：The generating set of the present invention has been filled up the super of 50MW-200MW power grades and facedThe blank of boundary's carbon dioxide recycle generating set；It is not required in 50MW-200MW power grades between turbine set and generating setWant gear reduction box so that unit is simply efficient；Using overall gear speed-increasing type compressor, it can allow compressor is at different levels to operate in mostExcellent rotating speed, so as to improve compressor aeroperformance.Its efficiency can be higher 2-3 percentage points than single-shaft multi-stage formula compressor.
Embodiment 1
A kind of generating set is present embodiments provided, especially a kind of supercritical carbon dioxide of 50~200MW grades followsRing generating set, including Systems of Centrifugal Compressor Unit, turbine set and generator.
The output shaft of the turbine set is connected with generator drive gear, and is passed with the gear wheel of the Systems of Centrifugal Compressor UnitDynamic connection, so that the generator when the turbine set works, can be driven to rotate, and cause the generator operation, andAnd can also Systems of Centrifugal Compressor Unit be driven to work.
The turbine set is the axial flow turbine of single-shaft multi-stage, or the unit for small-power grade, due to turbineThe import volume flow of group is smaller, and now the turbine set can include centripetal turbine and Multistage Axial Flow Turbines, described centripetalTurbine is connected in series with Multistage Axial Flow Turbines, in the present embodiment, the centripetal turbine be the turbine set the first order, high temperatureAfter the working medium of high pressure is expanded by centripetal turbine, volume flow increase, and drive the Multistage Axial Flow Turbines of series connection with it to rotate；The secondary speed of the turbine set is 3000r/min or 3600r/min.Directly shaft coupling can be passed through with common generatorDevice is coupled, it is not necessary to gear reduction unit.
In the present embodiment, the turbine set can be made up of a cylinder, and the working medium of HTHP is flowed into by inlet plenumThe expansion of first order turbine nozzle accelerates, and promotes turbine rotor blade rotation, subsequently enters following stages turbine nozzle expansion work, finally lead toCross exhaust chamber discharge.
Certainly, the turbine set can also be made up of two cylinders, including high pressure cylinder and low pressure (LP) cylinder.The working medium of HTHPIt is brought out, is heated in heat exchanger or combustion chamber, the working medium pressed in high temperature enters back into low pressure (LP) cylinder after into high pressure cylinder expansionExpansion work, it can so improve cycle efficieny.
When the turbine set includes two cylinders, the part level of Multistage Axial Flow Turbines is placed into high pressure cylinder, part level quiltIt is put into low pressure (LP) cylinder；Or centripetal turbine is placed into high pressure cylinder, Multistage Axial Flow Turbines are placed into low pressure (LP) cylinder etc..
Be connected with the turbine set by pipeline, after the working medium pressurization that the turbine set is discharged by regenerator andTurbine set is re-fed into after high temperature heater (HTH), to drive the turbine set to rotate；In the present embodiment, the regenerator can wrapHigh temperature regenerator and/or cryogenic regenerator are included, such as carbon dioxide respectively enters main compressor compression and recompression machine compression, it is mainNeed to pass through cryogenic regenerator and high temperature regenerator respectively after compressor compresses, and recompress after machine compresses by high temperature regenerator.
The Systems of Centrifugal Compressor Unit is overall gear speed-increasing type compressor set, i.e., described Systems of Centrifugal Compressor Unit includes a masterMovable gear shaft and multiple driven gear shafts, the driving gear shaft and driven gear shaft are parallel to each other；As one embodiment, instituteThe quantity for stating driven gear shaft is 2, is provided with gear wheel on the driving gear shaft, is provided with the driven gear shaft smallGear, the gear wheel and pinion fits, so as to form step-up drive between driving gear shaft and driven gear shaft；It is more excellentSelection of land, the both ends of the driven gear shaft are connected with centrifugal compressor stage.In the present embodiment, the centrifugal compressor stageIncluding entry guide vane, centrifugal impeller (semi-open type either enclosed), vane diffuser or vaneless diffuser and exhaust volute, centrifugationThe entry guide vane and exit vane diffusion of compressor stage can carry out angular adjustment by governor motion, to change the work of compressorMake state, meet the service requirement under different operating modes.
In the present embodiment, the driven gear shaft includes the first driven gear shaft and the second driven gear shaft；The centrifugationCompressor set includes main compressor and recompression machine；The main compressor and recompression machine are two-stage compressor, the main pressureThe two-stage centrifugal impeller of contracting machine is connected with the both ends of the first driven gear shaft respectively, the two-stage centrifugal leaf of the recompression machineWheel is connected with the both ends of the second driven gear shaft respectively；Or the two-stage centrifugal impeller of the main compressor is respectively withOne driven gear shaft and the drive connection of the second driven gear shaft, the two-stage centrifugal impeller of the recompression machine are driven with first respectivelyGear shaft and the drive connection of the second driven gear shaft.
In the present embodiment, first driven gear shaft is different from the rotating speed of the second driven gear shaft, that is to say, that installationIn the number of teeth of the gear on first driven gear shaft and the second driven gear shaft be different, so as to meet compressor stageOptimum speed, realize optimum efficiency.
Preferably, the air inlet of the main compressor first order connects with the exhaust outlet of turbine set, the main compressorThe exhaust outlet of the first order connects with the air inlet of the main compressor second level, the exhaust outlet and gas of the main compressor second levelThe low-pressure inlet connection of body injector；The air inlet of the recompression machine first order connects with the exhaust outlet of turbine set, describedThe exhaust outlet of the recompression machine first order connects with the air inlet of the recompression machine second level, the exhaust outlet of the recompression machine second levelConnected with the high pressure entry of gas ejector, the exhaust outlet of the gas ejector is entered by high temperature heater (HTH) and turbine setGas port connects.
In the present embodiment, the generating set also includes high temperature regenerator, cryogenic regenerator and cooler；The gas sprayThe exhaust outlet of emitter is connected by high temperature regenerator and high temperature heater (HTH) with the air inlet of turbine set；The row of the turbine setGas port is connected by high temperature regenerator, cryogenic regenerator and cooler with the air inlet of the main compressor first order respectively；AndAnd the exhaust outlet of the turbine set entering by high temperature regenerator and cryogenic regenerator and the recompression machine first order respectivelyGas port connects；And the exhaust outlet of the main compressor first order is connected by the low-pressure inlet of cryogenic regenerator and gas ejectorIt is logical.
At work, cycle fluid enters the generating set of the present embodiment from main compressor, by entry guide vane, flows into highThe centrifugal impeller of speed rotation, the working medium of high speed and high pressure is slowed down after impeller discharge by diffuser to be pressurized, and is then received by spiral caseSecond level import is discharged into after collection., can between the main compressor first order and the main compressor second level in order to reduce compression power consumptionTo increase intercooler, main compressor second level inlet temperature, similarly, the recompression machine first order and recompression are reducedIntercooler can be increased between the machine second level.
Under accidental conditions, the inlet and outlet pressure of main compressor and recompression machine is basically identical.But main compression importTemperature will be less than recompression machine inlet temperature, so the energy head of main compression is less than recompression machine.But in start-up course, it is mainCompressor and recompression machine inlet pressure are of substantially equal, and inlet temperature is of substantially equal or difference is smaller.Due to two compressorsRelative rotation speed it is constant, so the energy head of main compression is less than recompression machine, that is to say, that the outlet pressure of main compressor is less thanThe outlet pressure of recompression machine.Because outlet of the main compressor after cryogenic regenerator and the outlet for recompressing machine are finally to connectTogether.Because recompression outlet pressure is high, main compressor can be caused to enter surging condition.
, can be by adjusting main compressor and recompressing the entry guide vane and exit vane diffuser of machine in real processApproach the two outlet pressure.On the other hand, a gas ejector is set, it is low by the recompression machine exhaust air suction of high pressureThe main compressor exhaust of pressure, eventually forms the mixing exhaust pressed in one.It can avoid causing larger loss using valve decompression.So, as early as possible carbon dioxide working medium can be flowed in the state of big flow, high pressure in start-up course, accelerates to startProcess, while protect main compressor will not surge.
The generating set of the present invention under the operating mode of stable operation, the CO 2 fluid of high pressure by high-temperature heat-exchanging itBecome the CO 2 fluid of HTHP afterwards.By expanding power output after turbine set；The rotating speed of turbine set is3000r/min or 3600r/min.
Low pressure CO 2 fluid after being expanded in turbine set, still with higher temperature, successively by high temperature backheatDevice and cryogenic regenerator, transfer heat to the fluid of low temperature side.
The fluid come out from cryogenic regenerator is divided into two-way.Cooler is entered by pipeline all the way, passes through recirculated cooling waterOr CO 2 fluid is cooled to lower temperature by other low-temperature receivers, then, the first order of main compressor is entered, led to after compressionCross pipeline and enter the main compressor second level, the high-pressure carbon dioxide fluid after the compression of two-stage main compressor is entered by pipelineEnter cryogenic regenerator, heated by turbine set exhaust or waste heat used heat in cryogenic regenerator, the fluid after heating passes through pipelineInto the low-pressure inlet of gas ejector.
Another way low pressure CO 2 fluid enters the first order of recompression machine by pipeline, is entered after compression by pipelineThe mouth recompression machine second level, after recompressing machine two stages of compression, the high pressure entry of gas ejector is entered by pipeline,High temperature regenerator is entered by pipeline after two fluids mixing, air-flow enters high temperature and exchanged heat after being heated by high temperature regeneratorDevice heats.
During stable operation, because the pressure at expulsion of main compressor and recompression machine is of substantially equal, adjustment gas sprayThe throat opening area of emitter, gas ejector only play blending, reduce the losses by mixture of fluid.During stable operation,To reduce unit power output, the angle for the entry guide vane for changing main compressor and recompression machine can be passed through so that compressorInlet air flow is just to prewhirl.According to vane diffuser scheme, while adjust the setting angle of vane diffuser.Ensureing pressure ratioIn the case of consistent, the flow of compressor is reduced.The heat exchange amount of high-temperature heat-exchanging is reduced simultaneously, so as to change the defeated of electricity generation systemGo out power.
In start-up course, the exits and entrances valve of turbine set is first shut off, the bypass line of turbine is opened, is filled with dioxyChange carbon flow body, ensure that the fluid density in turbine set is relatively low, generator is switched to the state of motor, driving turbine set withAnd main compressor and recompression machine, now high-temperature heat-exchanging not yet works, so the main compressor first order and recompression machine firstInlet temperature, the pressure of level are of substantially equal, because the energy head of main compressor is less than the energy head of recompression machine.
So the Fluid pressure in the gas exhaust piping of main compressor is significantly lower than the fluid pressure of the gas exhaust piping of recompression machinePower, the acceleration and pressure decrease in gas ejector of the high pressure draught in the gas exhaust piping of machine is recompressed, in throat position by main compressorGas exhaust piping in low-pressure fluid suction, then mixing slows down supercharging, and is transported to turbine set；The gas ejectorDischarge line in Fluid pressure between recompression machine the Fluid pressure of gas exhaust piping and the gas exhaust piping of main compressorBetween Fluid pressure, the energy of high-pressure fluid can be so made full use of so that when inputting same power to compressor set, can obtainBigger carbon dioxide recycle flow is obtained, improves the efficiency that system starts, reduces system start-up time, ensures that start-up course is compressedMachine safe operation.
After machine stable operation to be compressed, high temperature heater (HTH) is started working.Then, the exits and entrances valve of turbine set is opened,Bypass line is closed.Turbine set and generator drive Systems of Centrifugal Compressor Unit to work simultaneously.As temperature raises, circular flow increasesGreatly, the output work increase of turbine set.Generator is switched to Generator Status, turbine set driving Systems of Centrifugal Compressor Unit and generatingMachine, external electromotive power output.
The generating set of the present embodiment, its Systems of Centrifugal Compressor Unit have by entry guide vane and exit vane diffuser joint debuggingEffect adds compressor flowrate adjustable range, while ensures that machine is compressed under most of operating mode has higher efficiency.Compressor goes outMouthful use gas ejector, start-up course can be accelerated, at the same protect main compressor will not surge, raising starting efficiency.TurbineUnit easily realizes the measure of compressor cooling during rolling and turbine resuperheat, can improve cycle efficieny.
The sequencing of above example only for ease of describing, does not represent the quality of embodiment.
Finally it should be noted that：The above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations；AlthoughThe present invention is described in detail with reference to the foregoing embodiments, it will be understood by those within the art that：It still may be usedTo be modified to the technical scheme described in foregoing embodiments, or equivalent substitution is carried out to which part technical characteristic；And these modification or replace, do not make appropriate technical solution essence depart from various embodiments of the present invention technical scheme spirit andScope.