CN113898434A - Turbine adjusting method for step gear load box type carbon dioxide power generation test platform - Google Patents

Turbine adjusting method for step gear load box type carbon dioxide power generation test platform Download PDF

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CN113898434A
CN113898434A CN202111212136.5A CN202111212136A CN113898434A CN 113898434 A CN113898434 A CN 113898434A CN 202111212136 A CN202111212136 A CN 202111212136A CN 113898434 A CN113898434 A CN 113898434A
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pressure turbine
low
power
inlet
load box
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李凯伦
李红智
姚明宇
张一帆
敬小磊
吴家荣
蒋世希
杨乐
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Xian Thermal Power Research Institute Co Ltd
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Xian Thermal Power Research Institute Co Ltd
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K25/00—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for
    • F01K25/08—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for using special vapours
    • F01K25/10—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for using special vapours the vapours being cold, e.g. ammonia, carbon dioxide, ether
    • F01K25/103—Carbon dioxide
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D15/00—Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
    • F01D15/10—Adaptations for driving, or combinations with, electric generators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D17/00—Regulating or controlling by varying flow
    • F01D17/10—Final actuators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D21/00—Shutting-down of machines or engines, e.g. in emergency; Regulating, controlling, or safety means not otherwise provided for
    • F01D21/003—Arrangements for testing or measuring
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K13/00—General layout or general methods of operation of complete plants
    • F01K13/02—Controlling, e.g. stopping or starting
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K7/00—Steam 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
    • F01K7/02—Steam 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 of multiple-expansion type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K7/00—Steam 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
    • F01K7/16—Steam 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

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

Abstract

The turbine adjusting method for the stepped gear load box type carbon dioxide power generation test platform comprises a heater, wherein an outlet pipeline of the heater is respectively connected with a high-pressure turbine inlet throttle and a high-pressure turbine bypass throttle inlet pipeline, the high-pressure turbine inlet throttle is connected with a high-pressure turbine, an outlet of the high-pressure turbine is converged with an outlet of the high-pressure turbine bypass throttle, the reheater inlet is connected together, the reheated gas is respectively connected with the low-pressure turbine inlet throttle and the low-pressure turbine bypass throttle, the low-pressure turbine inlet throttle is connected with the low-pressure turbine, and after the low-pressure turbine is converged with the low-pressure turbine bypass throttle, the hot side of the heat regenerator is connected together, an outlet of the hot side of the heat regenerator is connected with an inlet of a precooler after being converged with an outlet of a working medium supplementing valve, the precooler is connected to an inlet regulating valve of a compressor, the inlet regulating valve of the compressor is connected to the compressor, the compressor is connected to the cold side of the heat regenerator, and the cold side of the heat regenerator is connected with a heater. The invention is used for high-pressure and low-pressure turbine regulation of a step gear power generation load box type carbon dioxide power generation test platform.

Description

Turbine adjusting method for step gear load box type carbon dioxide power generation test platform
Technical Field
The invention belongs to the technical field of supercritical carbon dioxide cycle power generation, and particularly relates to a turbine adjusting method for a stepped gear load box type carbon dioxide power generation test platform.
Background
For the current supercritical carbon dioxide cycle power generation test platform, the cycle is a closed system, the inlet valve adjusting action of the high-pressure turbine can simultaneously influence the power values of the high-pressure turbine and the low-pressure turbine in actual regulation operation, and the inlet valve adjusting action of the low-pressure turbine can also simultaneously influence the power values of the high-pressure turbine and the low-pressure turbine, namely the valve opening of the high-pressure turbine and the power values of the high-pressure turbine and the low-pressure turbine are mutually coupled and influenced. Simultaneously, because present carbon dioxide generating set all is in the test stage, its produced electric energy can not direct input electric wire netting, can only adopt generator load case to consume, and present domestic carbon dioxide test platform adopts cascaded generator load case mostly, and the load case can not carry out power adjustment continuously, can only carry out cascaded gear and adjust, and adjacent cascaded gear power interval delta P is 50 ~ 200 kW.
Therefore, for the load box type carbon dioxide power generation test platform of the step gear generator, on one hand, the high-pressure turbine and the low-pressure turbine can be mutually coupled and influenced during adjustment, on the other hand, the load box of the step gear generator cannot continuously adjust the power generation, and the two factors are entangled, so that the high-pressure turbine and the low-pressure turbine of the existing supercritical carbon dioxide cycle power generation test platform are very difficult to adjust.
Disclosure of Invention
In order to overcome the technical problem, the invention provides a method for adjusting a turbine of a step gear load box type carbon dioxide power generation test platform, which is used for adjusting a high-pressure turbine and a low-pressure turbine of the step gear power generation load box type carbon dioxide power generation test platform.
In order to achieve the purpose, the invention adopts the technical scheme that:
a step gear load box type carbon dioxide power generation test platform turbine regulating system comprises a heater 1, wherein an outlet of the heater 1 is respectively connected with an inlet channel of a high-pressure turbine inlet regulating valve 2 and an inlet of a high-pressure turbine bypass regulating valve 3, an outlet of the high-pressure turbine inlet regulating valve 2 is connected with an inlet of a high-pressure turbine 4, an outlet of the high-pressure turbine 4 is connected with an outlet of the high-pressure turbine bypass regulating valve 3 after being converged and then is jointly connected with an inlet of a reheater 5, an outlet of the reheated gas 5 is respectively connected with an inlet of a low-pressure turbine inlet regulating valve 6 and an inlet of a low-pressure turbine bypass regulating valve 7, an outlet of the low-pressure turbine inlet regulating valve 6 is connected with an inlet of a low-pressure turbine 8, an outlet of the low-pressure turbine 8 is connected with an outlet of the low-pressure turbine bypass regulating valve 7 after being converged and then is jointly connected with an inlet of a heat regenerator 9, an outlet of the heat regenerator 9 is connected with an inlet of a precooler 11 after being converged with an outlet of a working medium supplementing valve 10, an outlet of the precooler 11 is connected with an inlet regulating valve 12, the outlet of the compressor inlet valve 12 is connected to the inlet of the compressor 13, the outlet of the compressor 13 is connected to the cold side inlet of the regenerator 9, and the cold side outlet of the regenerator 9 is connected with the inlet of the heater 1.
High-pressure turbine generator 14 adopts the coupling joint with high-pressure turbine 4, low pressure turbine generator 15 adopts the coupling joint with low pressure turbine 8, high pressure turbine generator load case 16 passes through circuit connection with high pressure turbine generator 14, low pressure turbine generator load case 17 passes through circuit connection with low pressure turbine generator 15 for the electric energy that the consumption generator sent, wherein high pressure turbine generator load case 16 is step gear regulation formula with low pressure turbine generator load case 17, adjust the electric power delta P who increases or reduce at every turn 50 ~ 200 kW.
A step gear load box type carbon dioxide power generation test platform turbine adjusting method comprises the following steps;
when the unit is started, the high-pressure turbine inlet throttle 2 and the low-pressure turbine inlet throttle 6 are kept completely closed, the opening degrees of the high-pressure turbine bypass throttle 3 and the low-pressure turbine bypass throttle 7 are kept at 100%, the opening degree of the working medium supplement valve 10 is kept at 100%, the compressor 13 is started to keep the working medium circulating in the loop, the power of the heater 1 is gradually increased until the temperature of the working medium before the high-pressure turbine inlet throttle 2 reaches 250-300 ℃, the high-pressure turbine bypass throttle 3 is gradually reduced, the power of the heater 1 and the power of the compressor 13 are continuously increased until the pressure of the working medium before the high-pressure turbine inlet throttle 2 reaches 16-17 MPa, when the temperature of the working medium reaches 300-350 ℃, the bypass regulating valve 3 of the high-pressure turbine is gradually closed, the inlet regulating valve 2 of the high-pressure turbine is gradually opened, the power of the heater 1 and the power of the compressor 13 are continuously increased, the target rotating speed of the high-pressure turbine 4 is set, and the impulse rotation of the high-pressure turbine 4 is started;
in the operation process of the unit, the high-pressure turbine bypass damper 3 and the low-pressure turbine bypass damper 7 are kept in a closed state, carbon dioxide working media enter the compressor 13 after being cooled by the precooler 11, enter the cold side of the heat regenerator 9 for heating after being boosted by the compressor 13, then enter the high-pressure turbine 4 for doing work after being heated again by the heater 1, continue to enter the low-pressure turbine 8 for doing work after being heated again by the reheater 5, exhaust gas is cooled by the hot side of the heat regenerator 9 after being used, the cooled working media return to the inlet of the precooler 11 again, so that a complete cycle is completed, and the working media supplement valve 10 is used for supplementing or releasing the working media to the system in the process of lifting loads.
When the high-pressure turbine 4 and the low-pressure turbine 8 are rushed to rotate, the rated rotating speed N of the high-pressure turbine 4 and the rated rotating speed N of the low-pressure turbine 8 are adjustedRThe method comprises the following steps of dividing the rotary table into a plurality of sections for segmental impact rotation, namely respectively setting a plurality of target rotating speeds: n is a radical of1＝(15％-20％)*NR；N2＝(30％-35％)*NR；N3＝(45％-55％)*NR；N3＝(45％-55％)*NR；N4＝(75％-85％)*NR；N5＝NR(ii) a And keeping the target rotating speed and the critical rotating speed of each stage of the rotor to keep an avoidance rate of more than 10 percent, gradually closing the bypass regulating gate 3 to 0 percent of the high-pressure turbine, gradually opening the inlet regulating gate 2 to 100 percent of the high-pressure turbine, and gradually increasing the power of the heater 1 and the power of the compressor 13 until the high-pressure turbine 4 reaches the target rotating speed N1Then, keeping the opening degree and power of each adjusting door and equipment of the system unchanged, stabilizing for 30min, and continuing to rush to N2Repeating the above operations until the high pressure turbine reaches NRAnd after stabilizing for 30min, finishing the process of the high-pressure turbine 4 impact rotation.
The high-pressure turbine 4 completes the impact rotation and reaches the rated rotating speed NRThen, the output power P of the high pressure turbine 4 is calculated according to the mass flow and the inlet and outlet temperature pressure of the high pressure turbine 4 at the momentgiAnd further the output torque of the high pressure turbine 4 can be calculated
Figure BDA0003309257810000041
Wherein P isgiThe unit is kW, NRThe unit is r/min, TdiIn Nm; the change DeltaN of the turbine speed is calculated when the output power of the high-pressure turbine 4 is not changed and the power of the load box 16 of the high-pressure turbine generator is increased or decreased by DeltaPgiComprises the following steps:
Figure BDA0003309257810000042
to ensure that the turbine speed does not overspeed or enter the critical speed range when changing, a check is required to ensure Δ Ngi/2≤9％*NR(ii) a After the data are obtained, the power of the heater 1 and the power of the compressor 13 are gradually increased, and the opening of other valves is kept unchanged, so that the rotating speed of the high-pressure turbine 4 is increased to
Figure BDA0003309257810000043
Then, the power gear of the generator load box is adjusted to be Pgn+ Δ P, the rotation speed of the high-pressure turbine 4 is suddenly reduced to
Figure BDA0003309257810000044
The power of the heater 1 and the power of the compressor 13 are gradually increased, and the rotating speed of the high-pressure turbine 4 is increased to NR(ii) a Repeatedly calculating the real-time output power P of the high-pressure turbine 4 by using the real-time mass flow and the inlet and outlet temperature pressuregiAnd calculating the turbine real-time torque TgiAnd change in rotational speed Δ NgiThe steps are repeated circularly to adjust the power of the high-pressure turbine to the target power value, and similarly, the method in the step is adopted to calculate the real-time power P of the low-pressure turbine 8diWhen the low-pressure turbine load box 17 is increased or decreased by Δ P while being kept constant, the rotation speed of the low-pressure turbine 8 is changed by Δ Ndi。
Estimating the value P of the no-load power of the low-pressure turbine by using historical data or operating data of the high-pressure turbine 4dnRaising the power generation power value of the high-pressure turbine 4 to (120-150%) PdnThen, gradually closing the low-pressure turbine bypass adjusting door 7, gradually opening the high-pressure turbine inlet adjusting door 6, gradually increasing the power of the reheater 5, and performing impact rotation on the low-pressure turbine 8 by the high-pressure turbine 4 impact rotation method, wherein the energy conservation of the stored working medium in the circulating system inevitably causes the reduction of the rotating speed of the high-pressure turbine 4 in the impact rotation and speed increasing process of the low-pressure turbine 8, and when the rotating speed of the high-pressure turbine 4 is reduced to the rotating speed in the step 4
Figure BDA0003309257810000051
When the power of the generator load box of the high-pressure turbine 4 needs to be reduced by one step, that is, after the power of the high-pressure turbine generator load box 16 is reduced by Δ P, the rotating speed of the high-pressure turbine 4 will suddenly increase to
Figure BDA0003309257810000052
The rotational speed of the low-pressure turbine 8 is increased further, so that the rotational speed of the high-pressure turbine 4 is reduced further, and the above steps are repeated until the low-pressure turbine 8 reaches its rated rotational speed NR；
After the above operation is completed, the high-pressure turbine rotating speed and the low-pressure turbine rotating speed are respectively positioned at [ N ]R-ΔNgi/2,NR+ΔNgi/2]And [ NR-ΔNdi/2,NR+ΔNdi/2]Within a range of rotational speeds byRespectively keeping the high-pressure turbine inlet regulating valve 2 and the low-pressure turbine inlet regulating valve 6 at 70-80%, and continuously and gradually increasing the power of the compressor 13, the heater 1 and the reheater 5, when the rotating speed of the high-pressure turbine 4 reaches NR+ΔNgi(iii)/2, increasing the power of the load box 16 of the high-pressure turbine generator by delta P, so as to suddenly reduce the rotating speed of the high-pressure turbine 4 to NR-ΔNgi2; when the low-pressure turbine 8 reaches NR+ΔNdiAt/2, the power of the load box 17 of the low-pressure turbine generator is increased by delta P, so that the rotating speed of the low-pressure turbine 8 is suddenly reduced to NR-ΔNdi2; repeating the above operations can continuously improve the output power of the high-pressure turbine 4 and the low-pressure turbine 8 and the power of the generator load box;
when the turbine output power needs to be reduced, the high-pressure turbine inlet adjusting valve 2 and the low-pressure turbine inlet adjusting valve 6 are kept unchanged, the power of the compressor 13, the heater 1 and the reheater 5 is gradually reduced, and when the rotating speed of the high-pressure turbine 4 is reduced to NR-ΔNgi(ii)/2, reducing the power of the load box 16 of the high-pressure turbine generator by delta P; when the rotational speed of low-pressure turbine 8 is reduced to NR-ΔNdiWhen the load is/2, reducing the power of the load box 17 of the low-pressure turbine generator by delta P; repeating the above operations can continuously reduce the output power of the high-pressure turbine 4 and the low-pressure turbine 8 and the power of the generator load box; through the repeated operation, the total power generation power of the high-pressure turbine and the low-pressure turbine can always reach the target power value;
when the total power of the high-low pressure turbine reaches the target power value, the rotating speeds of the high-low pressure turbine and the low-low pressure turbine are respectively positioned at [ N ]R-ΔNgi/2,NR+ΔNgi/2]And [ NR-ΔNdi/2,NR+ΔNdi/2]Within the rotating speed range, the high-pressure turbine inlet regulating valve 2 and the low-pressure turbine inlet regulating valve 6 are finely adjusted, and the power of the compressor 13, the heater 1 and the reheater 5 is properly increased, so that the rotating speeds of the high-pressure turbine and the low-pressure turbine reach the rated rotating speed N of the high-pressure turbine and the low-pressure turbineRTherefore, the regulation of the power generated by the high-low pressure turbine is completed.
The invention has the beneficial effects that:
because the high-pressure turbine and the low-pressure turbine of the carbon dioxide power generation test platform are arranged in a closed series connection mode, the high-pressure turbine and the low-pressure turbine can mutually influence when the valves are adjusted, meanwhile, the power of the generator cannot be continuously adjusted because the load box of the generator is in a step gear mode, and the power value of the high-pressure and low-pressure turbine is very difficult to adjust in the operation process. The method calculates the real-time torque corresponding to the real-time power of the high-pressure turbine and the low-pressure turbine, further calculates the rotating speed sudden change value corresponding to the high-pressure turbine and the low-pressure turbine when the real-time power of the generator load box suddenly changes delta P through the real-time torque, so that the rotating speed of the turbine is increased or decreased by half of the rotating speed sudden change value in advance during adjustment, then the power of the generator load box is adjusted, and the power is adjusted in a reciprocating manner, so that the total power of the high-pressure turbine and the low-pressure turbine can reach a target value.
Drawings
FIG. 1 is a flow chart of the system of the present invention.
Detailed Description
The present invention will be described in further detail with reference to examples.
The invention provides a turbine adjusting method for a stepped gear load box type carbon dioxide power generation test platform, as shown in figure 1, an outlet pipeline of a heater 1 is connected with an inlet pipeline of a high-pressure turbine inlet throttle 2 and an inlet pipeline of a high-pressure turbine bypass throttle 3, an outlet of the high-pressure turbine inlet throttle 2 is connected with an inlet of a high-pressure turbine 4, an outlet of the high-pressure turbine 4 is connected with an outlet of the high-pressure turbine bypass throttle 3 after being converged and then is connected with an inlet of a reheater 5, an outlet of reheated gas 5 is respectively connected with an inlet of a low-pressure turbine inlet throttle 6 and an inlet of a low-pressure turbine bypass throttle 7, an outlet of the low-pressure turbine inlet throttle 6 is connected with an inlet of a low-pressure turbine 8, an outlet of the low-pressure turbine 8 is connected with an inlet of a reheater 9 after being converged with an outlet of the low-pressure turbine bypass throttle 7, an outlet of the hot side reheater 9 is connected with an outlet of a working medium supplement valve 10 and then is connected with an inlet of a precooler 11, the outlet of the precooler 11 is connected to the inlet of a compressor inlet adjusting door 12, the outlet of the compressor inlet adjusting door 12 is connected to the inlet of a compressor 13, the outlet of the compressor 13 is connected to the cold side inlet of the heat regenerator 9, and the cold side outlet of the heat regenerator 9 is connected with the inlet of the heater 1. In the operation process of the unit, the high-pressure turbine bypass damper 3 and the low-pressure turbine bypass damper 7 are kept in a closed state, carbon dioxide working media enter the compressor 13 after being cooled by the precooler 11, enter the cold side of the heat regenerator 9 for heating after being boosted by the compressor 13, then enter the high-pressure turbine 4 for doing work after being heated again by the heater 1, continue to enter the low-pressure turbine 8 for doing work after being heated again by the reheater 5, exhaust gas is cooled by the hot side of the heat regenerator 9 after being used, the cooled working media return to the inlet of the precooler 11 again, so that a complete cycle is completed, and the working media supplement valve 10 is used for supplementing or releasing the working media to the system in the process of lifting loads. The high-pressure turbine generator 14 (low-pressure turbine generator 15) is connected with the high-pressure turbine 4 (low-pressure turbine 8) by a coupler, and the high-pressure turbine generator load box 16 (low-pressure turbine generator load box 17) is connected with the high-pressure turbine generator 14 (low-pressure turbine generator 15) by a circuit and used for consuming electric energy generated by the generator. The high-pressure turbine generator load box 16 and the low-pressure turbine generator load box 17 are step-gear adjustable, and the electric power delta P increased or decreased by each adjustment is 50-200 kW.
In the carbon dioxide power generation test system shown in fig. 1, the high-pressure turbine and the low-pressure turbine are arranged in a closed series manner, the high-pressure turbine and the low-pressure turbine can mutually influence each other when valves are adjusted, and meanwhile, a generator load box is in a step gear type, and the power of a generator cannot be continuously adjusted, so that the power generation values of the high-pressure turbine and the low-pressure turbine are very difficult to adjust in the operation process of the test platform, and the following technical scheme is provided for this purpose, and the technical key points in the implementation process of the invention are as follows:
1. when the unit is started, the high-pressure turbine inlet throttle 2 and the low-pressure turbine inlet throttle 6 are kept completely closed, the opening degrees of the high-pressure turbine bypass throttle 3 and the low-pressure turbine bypass throttle 7 are kept at 100%, the opening degree of the working medium supplement valve 10 is kept at 100%, the compressor 13 is started to keep the working medium circulating in the loop, the power of the heater 1 is gradually increased until the temperature of the working medium before the high-pressure turbine inlet throttle 2 reaches 250-300 ℃, the high-pressure turbine bypass throttle 3 is gradually reduced, the power of the heater 1 and the power of the compressor 13 are continuously increased until the pressure of the working medium before the high-pressure turbine inlet throttle 2 reaches 16-17 MPa, when the temperature of the working medium reaches 300-350 ℃, the bypass regulating valve 3 of the high-pressure turbine is gradually closed, the inlet regulating valve 2 of the high-pressure turbine is gradually opened, the power of the heater 1 and the power of the compressor 13 are continuously increased, the target rotating speed of the high-pressure turbine 4 is set, and the high-pressure turbine 4 starts to rotate by impact.
2. When the high-pressure turbine 4 and the low-pressure turbine 8 are rotating, the rated rotation speed of the high-pressure turbine 4 and the low-pressure turbine 8 is assumed to be NRSpecially designed for the rated speed N to avoid the excessive temperature difference between the inner and outer walls of the turbine cylinderRThe method comprises the following steps of dividing the rotary table into a plurality of sections for segmental impact rotation, namely respectively setting a plurality of target rotating speeds: n is a radical of1＝(15％-20％)*NR；N2＝(30％-35％)*NR；N3＝(45％-55％)*NR；N3＝(45％-55％)*NR；N4＝(75％-85％)*NR；N5＝NR(ii) a And keeping the target rotating speed and the critical rotating speed of each stage of the rotor to keep the avoidance rate of more than 10%. During the turbine rush-rotation period, gradually closing the high-pressure turbine bypass adjusting door 3 to 0 percent, gradually opening the high-pressure turbine inlet adjusting door 2 to 100 percent, and gradually increasing the power of the heater 1 and the power of the compressor 13 until the high-pressure turbine 4 reaches the target rotation speed N1Then, keeping the opening degree and power of each adjusting door and equipment of the system unchanged, stabilizing for 30min, and continuing to rush to N2Repeating the above operations until the high pressure turbine reaches NRAnd after stabilizing for 30min, finishing the process of the high-pressure turbine 4 impact rotation.
3. The high-pressure turbine 4 completes the impact rotation and reaches the rated rotating speed NRThen, the output power P of the high pressure turbine 4 can be calculated by the mass flow and the inlet and outlet temperature pressure of the high pressure turbine 4 at this timegiAnd further the output torque of the high pressure turbine 4 can be calculated
Figure BDA0003309257810000091
Wherein P isgiThe unit is kW, NRThe unit is r/min, TdiIn Nm; it can be calculated that the change of the turbine speed deltaN is obtained when the output power of the high-pressure turbine 4 is not changed and the power of the load box 16 of the high-pressure turbine generator is increased or decreased by deltaPgiComprises the following steps:
Figure BDA0003309257810000092
to ensure that the turbine speed does not overspeed or enter the critical speed range when changing, a check is required to ensure Δ Ngi/2≤9％*NR(ii) a After the above data has been obtained, the data is obtained,the rotation speed of the high-pressure turbine 4 is increased to the value that the power of the heater 1 and the power of the compressor 13 are gradually increased and the opening of other valves is kept unchanged
Figure BDA0003309257810000093
Then, the power gear of the generator load box is adjusted to be Pgn+ Δ P, the rotation speed of the high-pressure turbine 4 is suddenly reduced to
Figure BDA0003309257810000101
The power of the heater 1 and the power of the compressor 13 are gradually increased, and the rotating speed of the high-pressure turbine 4 is increased to NR(ii) a Repeatedly calculating the real-time output power P of the high-pressure turbine 4 by using the real-time mass flow and the inlet and outlet temperature pressuregiAnd calculating the turbine real-time torque TgiAnd change in rotational speed Δ NgiAnd circularly repeating the steps to adjust the high-pressure turbine power to the target power value. By a similar method in this step, the real-time power P of the low-pressure turbine 8 can be calculateddiWhen the low-pressure turbine load box 17 is increased or decreased by Δ P while being kept constant, the rotation speed of the low-pressure turbine 8 is changed by Δ Ndi。
4. Estimating the no-load power value P of the low-pressure turbine by using historical data or high-pressure turbine operation datadnRaising the power value of the high-pressure turbine to 120-150% P by adopting the method of the step 3dnAnd then, gradually closing the low-pressure turbine bypass adjusting door 7, gradually opening the high-pressure turbine inlet adjusting door 6, gradually increasing the power of the reheater 5, and performing impact rotation on the low-pressure turbine 8 by adopting a similar method of impact rotation of the high-pressure turbine 4 in the step 3. Because the energy conservation of the stored working medium in the circulating system, the rotating speed of the high-pressure turbine 4 is inevitably reduced in the process of the impact, rotation and speed increase of the low-pressure turbine 8, and when the rotating speed of the high-pressure turbine 4 is reduced to that in the step 4
Figure BDA0003309257810000102
When the power of the generator load box of the high-pressure turbine 4 needs to be reduced by one step, that is, after the power of the high-pressure turbine generator load box 16 is reduced by Δ P, the rotating speed of the high-pressure turbine 4 will suddenly increase to
Figure BDA0003309257810000103
Continuing to increase the rotating speed of the low-pressure turbine according to the step 3, so that the rotating speed of the high-pressure turbine is continuously reduced, and repeating the steps until the low-pressure turbine reaches the rated rotating speed N of the low-pressure turbineR。
5. After the operation of step 4 is completed, the high-pressure turbine rotating speed and the low-pressure turbine rotating speed can be respectively positioned at [ N ]R-ΔNgi/2,NR+ΔNgi/2]And [ NR-ΔNdi/2,NR+ΔNdi/2]In the rotating speed range, the high-pressure turbine inlet regulating valve 2 and the low-pressure turbine inlet regulating valve 6 are respectively kept at 70% -80%, and meanwhile, the power of the compressor 13, the heater 1 and the reheater 5 is continuously and gradually increased, and when the rotating speed of the high-pressure turbine 4 reaches NR+ΔNgi(iii)/2, increasing the power of the load box 16 of the high-pressure turbine generator by delta P, so as to suddenly reduce the rotating speed of the high-pressure turbine 4 to NR-ΔNgi2; when the low-pressure turbine 8 reaches NR+ΔNdiAt/2, the power of the load box 17 of the low-pressure turbine generator is increased by delta P, so that the rotating speed of the low-pressure turbine 8 is suddenly reduced to NR-ΔNdi2; repeating the above operations can continuously improve the output power of the high-pressure turbine 4 and the low-pressure turbine 8 and the power of the generator load box; when the turbine output power needs to be reduced, the high-pressure turbine inlet adjusting valve 2 and the low-pressure turbine inlet adjusting valve 6 are kept unchanged, the power of the compressor 13, the heater 1 and the reheater 5 is gradually reduced, and when the rotating speed of the high-pressure turbine 4 is reduced to NR-ΔNgi(ii)/2, reducing the power of the load box 16 of the high-pressure turbine generator by delta P; when the rotational speed of low-pressure turbine 8 is reduced to NR-ΔNdiWhen the load is/2, reducing the power of the load box 17 of the low-pressure turbine generator by delta P; repeating the above operations can continuously reduce the output power of the high-pressure turbine 4 and the low-pressure turbine 8 and the power of the generator load box; through the repeated operation, the total power generation power of the high-pressure turbine and the low-pressure turbine can always reach the target power value.
6. When the total power of the high-low pressure turbine reaches the target power value, the rotating speeds of the high-low pressure turbine and the low-low pressure turbine are respectively positioned at [ N ]R-ΔNgi/2,NR+ΔNgi/2]And [ NR-ΔNdi/2,NR+ΔNdi/2]High pressure permeation by fine adjustment within a rotating speed rangeThe inlet regulating valve 2 and the inlet regulating valve 6 of the low-pressure turbine are leveled, and the power of the compressor 13, the heater 1 and the reheater 5 are properly increased, so that the rotating speeds of the high-pressure turbine and the low-pressure turbine reach the rated rotating speed NRTherefore, the regulation of the power generated by the high-low pressure turbine is completed.

Claims (6)

1. A step gear load box type carbon dioxide power generation test platform turbine adjusting system is characterized by comprising a heater (1), wherein an outlet of the heater (1) is respectively connected with an inlet of a high-pressure turbine inlet adjusting door (2) and an inlet of a high-pressure turbine bypass adjusting door (3), an outlet of the high-pressure turbine inlet adjusting door (2) is connected with an inlet of a high-pressure turbine (4), an outlet of the high-pressure turbine (4) is converged with an outlet of the high-pressure turbine bypass adjusting door (3) and then jointly connected to an inlet of a reheater (5), an outlet of a reheat gas (5) is respectively connected with an inlet of a low-pressure turbine inlet adjusting door (6) and an inlet of a low-pressure turbine bypass adjusting door (7), an outlet of the low-pressure turbine inlet adjusting door (6) is connected with an inlet of a low-pressure turbine (8), an outlet of the low-pressure turbine (8) is converged with an outlet of the low-pressure turbine bypass adjusting door (7) and then jointly connected to an inlet of a hot side of the reheater (9), an outlet of a hot side of the heat regenerator (9) is connected with an inlet of a precooler (11) after being converged with an outlet of a working medium supplementing valve (10), an outlet of the precooler (11) is connected to an inlet of a compressor inlet regulating valve (12), an outlet of the compressor inlet regulating valve (12) is connected to an inlet of a compressor (13), an outlet of the compressor (13) is connected to an inlet of a cold side of the heat regenerator (9), and an outlet of the cold side of the heat regenerator (9) is connected with an inlet of a heater (1).
2. The turbine regulating system of the stepped gear load box type carbon dioxide power generation test platform as claimed in claim 1, wherein the high-pressure turbine generator (14) is connected with the high-pressure turbine (4) through a coupler, the low-pressure turbine generator (15) is connected with the low-pressure turbine (8) through a coupler, the high-pressure turbine generator load box (16) is connected with the high-pressure turbine generator (14) through a circuit, the low-pressure turbine generator load box (17) is connected with the low-pressure turbine generator (15) through a circuit and used for consuming electric energy generated by the generator, the high-pressure turbine generator load box (16) and the low-pressure turbine generator load box (17) are in stepped gear regulation type, and electric power delta P increased or decreased in each regulation is 50-200 kW.
3. The method for regulating the turbine system of the step gear load box type carbon dioxide power generation test platform is characterized by comprising the following steps;
when the unit is started, the high-pressure turbine inlet adjusting door (2) and the low-pressure turbine inlet adjusting door (6) are kept closed completely, the opening degrees of the high-pressure turbine bypass adjusting door (3) and the low-pressure turbine bypass adjusting door (7) are kept at 100%, the opening degree of the working medium supplementing valve (10) is kept at 100%, the compressor (13) is started to keep the working medium circulating in a loop, the power of the heater (1) is gradually increased until the temperature of the working medium before the high-pressure turbine inlet adjusting door (2) reaches 250-300 ℃, the high-pressure turbine bypass adjusting door (3) is gradually closed, the power of the heater (1) and the power of the compressor (13) are continuously increased until the pressure of the working medium before the high-pressure turbine inlet adjusting door (2) reaches 16-17 MPa and the temperature of the working medium reaches 300-350 ℃, the high-pressure turbine inlet adjusting door (3) is started to be closed gradually, the high-pressure turbine inlet adjusting door (2) is opened gradually, the power of the heater (1) and the power of the compressor (13) are continuously increased, setting a target rotating speed of the high-pressure turbine (4), and starting the impact rotation of the high-pressure turbine (4);
in the operation process of the unit, a high-pressure turbine bypass adjusting valve (3) and a low-pressure turbine bypass adjusting valve (7) are kept in a closed state, a carbon dioxide working medium enters a compressor (13) after being cooled by a precooler (11), the carbon dioxide working medium enters a cold side of a heat regenerator (9) after being boosted by the compressor (13) to be heated, then the working medium enters a high-pressure turbine (4) to do work after being heated again by a heater (1), the working medium after doing work is reheated by a reheater (5) and continuously enters a low-pressure turbine (8) to do work, exhaust gas after doing work is cooled by the hot side of the heat regenerator (9), the cooled working medium returns to an inlet of the precooler (11) again, so that a complete cycle is completed, and a working medium supplementing valve (10) is used for supplementing or releasing the working medium to the system in the process of lifting loads.
4. The method for adjusting the turbine of the stepped-gear load box type carbon dioxide power generation test platform according to claim 3, wherein the high-pressure turbine (4) and the low-pressure turbine (8) are used for turning over the high-pressure turbine (4) and the low-pressure turbine (8) (C)8) Rated rotational speed NRThe method comprises the following steps of dividing the rotary table into a plurality of sections for segmental impact rotation, namely respectively setting a plurality of target rotating speeds: n is a radical of1＝(15％-20％)*NR；N2＝(30％-35％)*NR；N3＝(45％-55％)*NR；N3＝(45％-55％)*NR；N4＝(75％-85％)*NR；N5＝NR(ii) a And keeping the target rotating speed and the critical rotating speed of each stage of the rotor to keep an avoidance rate of more than 10 percent, gradually closing the bypass regulating gate 3 to 0 percent of the high-pressure turbine, gradually opening the inlet regulating gate 2 of the high-pressure turbine to 100 percent, and gradually increasing the power of the heater (1) and the power of the compressor (13) during the turbine rush period until the high-pressure turbine (4) reaches the target rotating speed N1Then, keeping the opening degree and power of each adjusting door and equipment of the system unchanged, stabilizing for 30min, and continuing to rush to N2Repeating the above operations until the high pressure turbine reaches NRAnd after stabilizing for 30min, finishing the process of the impact rotation of the high-pressure turbine (4).
5. The method for adjusting the turbine of the stepped gear load box type carbon dioxide power generation test platform according to claim 4, wherein the high-pressure turbine (4) completes the impact rotation and reaches a rated rotating speed NRThen, the output power P of the high-pressure turbine (4) is calculated according to the mass flow and the inlet-outlet temperature pressure of the high-pressure turbine (4) at the momentgiFurther calculate the output torque of the high pressure turbine (4)
Figure FDA0003309257800000031
Wherein P isgiThe unit is kW, NRThe unit is r/min, TdiIn Nm; calculating the change delta N of the turbine speed when the output power of the high-pressure turbine (4) is not changed and the power of the load box (16) of the high-pressure turbine generator is increased or decreased delta PgiComprises the following steps:
Figure FDA0003309257800000032
to ensure that the turbine speed does not overspeed or enter the critical speed range when changing, a check is required to ensure Δ Ngi/2≤9％*NR(ii) a After the data are obtained, the data are gradually extractedThe power of the heater (1) and the power of the compressor (13) are increased, and the opening of other valves is kept unchanged, so that the rotating speed of the high-pressure turbine (4) is increased to
Figure FDA0003309257800000033
Then, the power gear of the generator load box is adjusted to be Pgn+ delta P, the rotational speed of the high-pressure turbine (4) will suddenly drop
Figure FDA0003309257800000041
The power of the heater (1) and the power of the compressor (13) are gradually increased, and the rotating speed of the high-pressure turbine (4) is increased to NR(ii) a The real-time mass flow and the inlet and outlet temperature pressure of the high-pressure turbine (4) are repeatedly adopted to calculate the real-time output power PgiAnd calculating the turbine real-time torque TgiAnd change in rotational speed Δ NgiThe steps are repeated circularly to adjust the power of the high-pressure turbine to the target power value, and similarly, the method in the step is adopted to calculate the real-time power P of the low-pressure turbine (8)diWhen the low pressure turbine load box (17) is increased or decreased by delta P while keeping the same, the rotating speed of the low pressure turbine (8) is changed by delta Ndi。
6. The method for adjusting the turbine of the stepped-gear load box type carbon dioxide power generation test platform according to claim 3, wherein the no-load power value P of the low-pressure turbine is estimated by using historical data or operation data of the high-pressure turbine (4)dnRaising the power generation power value of the high-pressure turbine (4) to 120-150% PdnThen, gradually closing the low-pressure turbine bypass adjusting valve (7), gradually opening the high-pressure turbine inlet adjusting valve (6) and gradually increasing the power of the reheater (5), and performing impact rotation on the low-pressure turbine (8) by a method of impact rotation of the high-pressure turbine (4), wherein the energy conservation of the reserved working medium in the circulating system inevitably causes the reduction of the rotating speed of the high-pressure turbine (4) in the process of impact rotation and speed increase of the low-pressure turbine (8), and when the rotating speed of the high-pressure turbine (4) is reduced to the rotating speed in the step 4
Figure FDA0003309257800000042
When necessary, the generator of the high-pressure turbine (4) needs to be chargedThe load box power is reduced by one gear, namely after the power of the load box (16) of the high-pressure turbine generator is reduced by delta P, the rotating speed of the high-pressure turbine (4) is suddenly increased
Figure FDA0003309257800000043
The rotational speed of the low-pressure turbine (8) is increased continuously, so that the rotational speed of the high-pressure turbine (4) is reduced continuously, and the steps are repeated until the low-pressure turbine (8) reaches the rated rotational speed N thereofR；
After the above operation is completed, the high-pressure turbine rotating speed and the low-pressure turbine rotating speed are respectively positioned at [ N ]R-ΔNgi/2,NR+ΔNgi/2]And [ NR-ΔNdi/2,NR+ΔNdi/2]In the rotating speed range, the power of a compressor (13), a heater (1) and a reheater (5) is continuously and gradually increased by respectively keeping a high-pressure turbine inlet throttle valve (2) and a low-pressure turbine inlet throttle valve (6) at 70% -80%, and when the rotating speed of a high-pressure turbine (4) reaches NR+ΔNgi(iii)/2, increasing the power of the load box (16) of the high-pressure turbine generator by delta P, so as to reduce the speed of the high-pressure turbine (4) to NR-ΔNgi2; when the low-pressure turbine (8) reaches the rotating speed NR+ΔNdiAt/2, the power of the load box (17) of the low-pressure turbine generator is increased by delta P, so that the rotating speed of the low-pressure turbine (8) is suddenly reduced to NR-ΔNdi2; the operation is repeated to continuously increase the output power of the high-pressure turbine (4) and the low-pressure turbine (8) and the power of the load box of the generator;
when the turbine output power needs to be reduced, the high-pressure turbine inlet regulating valve (2) and the low-pressure turbine inlet regulating valve (6) are kept unchanged, the power of the compressor (13), the heater (1) and the reheater (5) is gradually reduced, and when the rotating speed of the high-pressure turbine (4) is reduced to NR-ΔNgi-2, reducing the power of the load box (16) of the high-pressure turbine generator by Δ P; when the rotational speed of the low-pressure turbine (8) is reduced to NR-ΔNdiWhen the power of the load box (17) of the low-pressure turbine generator is reduced by delta P at the time of/2; the operation is repeated to continuously reduce the output power of the high-pressure turbine (4) and the low-pressure turbine (8) and the power of a load box of the generator; through the repeated operation, the total power generation power of the high-pressure turbine and the low-pressure turbine can always reach the target power value;
when the total power of the high-low pressure turbine reaches the target power value, the rotating speeds of the high-low pressure turbine and the low-low pressure turbine are respectively positioned at [ N ]R-ΔNgi/2,NR+ΔNgi/2]And [ NR-ΔNdi/2,NR+ΔNdi/2]Within the rotating speed range, the high-pressure turbine inlet regulating valve (2) and the low-pressure turbine inlet regulating valve (6) are finely adjusted, and the power of the compressor (13), the heater (1) and the reheater (5) is increased, so that the rotating speeds of the high-pressure turbine and the low-pressure turbine reach the rated rotating speed N of the high-pressure turbine and the rated rotating speed N of the low-pressure turbineRTherefore, the regulation of the power generated by the high-low pressure turbine is completed.
CN202111212136.5A 2021-10-18 2021-10-18 Turbine adjusting method for step gear load box type carbon dioxide power generation test platform Withdrawn CN113898434A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115263476A (en) * 2022-08-03 2022-11-01 西安热工研究院有限公司 Control method of supercritical carbon dioxide series double-turbine power generation system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115263476A (en) * 2022-08-03 2022-11-01 西安热工研究院有限公司 Control method of supercritical carbon dioxide series double-turbine power generation system
CN115263476B (en) * 2022-08-03 2023-08-18 西安热工研究院有限公司 Control method of supercritical carbon dioxide serial double-turbine power generation system

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