Multi-constraint start-stop process evaluation method for combined cycle generator set

Abstract

The invention provides a combined cycle generator set multi-constraint start-stop process evaluation method, which comprises the following steps of: performing statistical analysis on each key index in the start-stop process of a combined cycle generator set by virtue of a large amount of historical operation data stored in a combined cycle generator set or a real-time database; according to the method, the start-stop process evaluation system is established, the optimal start-stop process under different start-stop working conditions is found, the optimal start-stop process serves as a standard start-stop process reference system and is continuously updated in a rolling mode, operation and adjustment can be conveniently conducted by an operator according to the optimal start-stop process, and the start-stop cost and the overall operation cost of the combined cycle generator set are reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of combined cycle units and relates to a multi-constraint start-stop process evaluation method for a combined cycle generator unit. Background Art

[0002] With the development of power generation technology in recent years, the installed capacity of combined cycle generators in the power grid has continued to increase, and they are responsible for important peak-shaving tasks. For combined cycle generators that undertake peak-shaving tasks, they are mostly operated in two shifts, with many starts and stops. The optimized operation and refined management of the start-stop process play an important role in improving the economic efficiency of unit operation.

[0003] Generally speaking, most combined cycle power generation units have standardized requirements for the start-up and shutdown process. However, in actual operation, due to different initial conditions and operation levels, it is difficult to achieve optimal operation during the start-up and shutdown process, and there are few comprehensive analysis and evaluation of the parameters of the start-up and shutdown process. At present, the evaluation of the start-up and shutdown process of the power generation unit is basically based on fixed flat indicators, without considering the actual conditions of the start-up and shutdown of the unit, and it is difficult to reflect the actual situation of the start-up and shutdown of the unit, which is not conducive to the continuous optimization and guidance of the start-up and shutdown process of the combined cycle power generation unit. Summary of the invention

[0004] Purpose of the invention: The purpose of the invention is to establish an accurate unit start-stop process evaluation system, establish the unit start-stop process evaluation system through data analysis, and ensure that the start-stop process evaluation system can truly reflect the unit start-stop process.

[0005] The present invention specifically provides a method for evaluating the multi-constraint start-stop process of a combined cycle generator set, comprising: by analyzing the start-stop process data of the combined cycle generator set, establishing a data model between key parameters of the start-stop process, and then establishing a unit start-up process evaluation system and a unit shutdown process evaluation system, wherein the establishment of the unit start-up process evaluation system comprises the following steps:

[0006] Step a1, establish data communication with the control system, obtain and store the unit operation data from the control system database, use Python language to write data analysis software that reads and analyzes data from the database, analyzes the unit start and stop process, including analyzing the start and stop initial state, start and stop time, start and stop process energy consumption and safety restrictions, and determines the key data that affects the unit start and stop process, the key data includes the engine speed, the engine generator active power, the unit AGC (the unit load is controlled by the power grid) input state, the engine consumption natural gas flow, the turbine high pressure cylinder expansion and water replenishment during the turbine start-up;

[0007] Step a2, determining the key nodes in the entire operation cycle of the unit from start to stop according to the unit operation procedures and the operation status of key equipment; the operation status of key equipment includes the gas turbine speed, gas turbine generator grid connection, steam turbine speed, steam turbine generator grid connection and AGC input status;

[0008] Step a3, taking the start of the gas turbine as the starting node of an operation cycle of the whole unit;

[0009] Step a4, after the gas turbine and the steam turbine are disconnected, the steam turbine cranking motor is started as the end node of one operation cycle of the whole unit;

[0010] Step a5, determining statistics of key indicators of the startup process, wherein the key indicators include the amount of plant electricity consumed during the startup process, the natural gas consumption of the gas turbine during the startup process, and the amount of makeup water consumed during the startup process;

[0011] Step a6, considering the startup efficiency and the safety of the startup process, analyzing the data of the existing startup process, determining the key factors affecting the unit startup process, finding out the relationship between the key factors and the startup process indicators, and establishing a startup process evaluation method;

[0012] Step a7, according to the existing startup process, data analysis and unit operation procedures are performed to determine that the key indicators affecting the unit operation safety are the upper and lower wall temperatures of the drum, vacuum, cylinder expansion and boiler temperature rise rate, and the normal startup of the gas turbine and the speed exceeding 5 rpm are the statistical start time;

[0013] Step a8, taking the statistical end time when the load of the entire unit exceeds 270MW and the AGC is put into operation, statistical analysis is performed on the parameters of the startup process to further complete the startup process evaluation method, and the evaluation process can be designed according to the operation requirements of the power plant.

[0014] In step a5, when the statistics of the power consumption of the plant during the startup process are collected, the start time and end time of the statistics of the power consumption of the plant are determined according to the operating characteristics of the unit (the main steps of the unit startup phase, including the equipment time analysis required for the steam turbine vacuum pumping, boiler water supply, water system water replenishment and equipment cooling);

[0015] When counting the natural gas consumption of the gas turbine during the startup process, the starting time of the statistics of the natural gas consumption of the gas turbine is determined according to the start time of the gas consumption during the startup process of the gas turbine, and the end time is when the load of the whole unit exceeds 270MW and the AGC is put into operation;

[0016] When counting the amount of make-up water consumed during the start-up and shutdown process, the start and end times of the statistics on the amount of make-up water consumed during the start-up and shutdown process shall be determined according to the operating characteristics of the unit;

[0017] Step a6 includes:

[0018] Step a6-1, analyzing the startup process of the combined cycle generator set and combining it with the requirements of the operating procedures, determining that the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up is the key factor affecting the startup process of the unit under various states;

[0019] Step a6-2, analyze and model the startup data to determine the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up and the time consumed in the startup process T = f T (x pz ), determine the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the start-up and the power consumption during the startup process E = f E (x pz ), determine the functional relationship between the expansion of the high-pressure cylinder of the turbine during the turbine run-up and the amount of natural gas consumed during the startup process G = f G (x pz ), determine the functional relationship between the expansion of the high-pressure cylinder of the turbine during the turbine run-up and the amount of make-up water consumed during the start-up process W = f W (x pz ), T is the unit startup process time, E is the power consumption during the startup process, G is the natural gas volume during the startup process, W is the water replenishment volume during the startup process, x pz The high pressure cylinder of the steam turbine expands when the turbine is running;

[0020] Step a6-3, based on the expansion of the high-pressure cylinder of the steam turbine during the actual turbine run-up, use T=f obtained in step a6-2 T (x pz ) function relationship, calculate the theoretical start-stop time T of the high-pressure cylinder of the steam turbine under the expansion of the steam turbine during the steam turbine rush targes , count the time T consumed in the actual start-stop process actual , startup process time score S time =S-(T actual -T target )×K T , S time The maximum is 100, the minimum is 0, K T is the time deviation coefficient of the startup process, S is the score benchmark value;

[0021] Step a6-4, based on the expansion of the high-pressure cylinder of the steam turbine during the actual turbine run-up, use E=f obtained in step a6-2 E (x pz ) function relationship, calculate the theoretical plant power consumption E under the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up target , calculate the actual power consumption E during the start-stop process actual , plant power consumption score S eng The calculation process is S eng =S-(E actual -E sarget )×K E , Seng The maximum is 100, the minimum is 0, K E is the deviation coefficient of plant power consumption;

[0022] Step a6-5, based on the expansion of the high-pressure cylinder of the steam turbine during the actual turbine run-up, use G=f obtained in step a6-2 G (x pz ) function relationship, calculate the theoretical natural gas consumption G under the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up target , calculate the actual natural gas consumption during the start-stop process G actual , natural gas consumption score S gas The calculation process is S gas =S-(G actual -G target )×K G , S gas The maximum is 100, the minimum is 0, K G is the natural gas consumption deviation coefficient;

[0023] Step a6-6, based on the expansion of the high-pressure cylinder of the steam turbine during the actual turbine run-up, use W=f obtained in step a6-2 W (x pz ) function relationship, calculate the water replenishment amount W under the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up target , calculate the actual amount of water consumed during the start-stop process W actual , water replenishment score S makeUpwater =S-(W actual -W target )×K W , S makeUpwater The maximum is 100, the minimum is 0, K W is the water replenishment deviation coefficient;

[0024] Step a6-7, start process scoring initial value S tem for:

[0025] S tem =S time ×W time +S eng ×W eng +S gas ×W gas +S makeUpwater ×W water ,

[0026] Among them, W time is the weight of the startup time score in the startup process evaluation, W eng is the weight of the power consumption score in the startup process evaluation, W gas is the weight of the gas turbine natural gas consumption score in the startup process evaluation, Wwater is the weight of the water replenishment score in the startup process evaluation, and the weight is obtained based on the correlation analysis of the existing start-stop data.

[0027] Step a7 includes: according to the unit operation management regulations and the unit equipment safety operation requirements, statistics are collected on the upper and lower wall temperatures of the drum, vacuum, cylinder expansion and boiler temperature rise rate data, and the time when the upper and lower wall temperature difference of the high-pressure drum is in different ranges is counted by minute, and the time T between 40℃ and 50℃ is counted. 40-50 The time T when the temperature difference between the upper and lower walls of the high-pressure drum is between 40℃ and 50℃ 50-60 The time T when the temperature difference between the upper and lower walls of the high-pressure drum is between 40℃ and 50℃ 60- The temperature difference between the upper and lower walls of the high-pressure steam drum is S Tdiv , S Tdiv The deduction calculation method is determined based on the impact of the temperature difference between the upper and lower walls of the high-pressure drum on the operation of the unit and the operation assessment regulations;

[0028] The time that the condenser vacuum exceeds the safe operation limit is counted in minutes, and recorded as T 16- , condenser vacuum deduction S V , S V The deduction calculation method is determined based on the impact of the condenser vacuum exceeding the safe operating limit on the unit operation and the operation assessment regulations;

[0029] The time when the steam turbine cylinder expansion exceeds the safe operation limit is counted in minutes, and recorded as T 9.5- , the deduction item for steam turbine cylinder expansion is S gz , S gz The deduction calculation method is determined based on the impact of the steam turbine cylinder over-expansion safety operating limit on the unit operation and the operation assessment regulations;

[0030] Statistical average boiler temperature rise rate T tUpavg , the boiler temperature rise rate deduction item is S Btup , S Btup The deduction calculation method is determined based on the impact of the average boiler temperature rise rate on the unit operation and the operation assessment regulations;

[0031] The overall rating for the startup process is S see :

[0032] S see =S tem -S Tdiv -S V -S gz -S Btup .

[0033] The establishment of the unit shutdown process evaluation system comprises the following steps:

[0034] Step b1, since the shutdown process is restricted by equipment and power grid requirements, the shutdown process evaluation system is carried out according to the actual situation of the power plant, and the shutdown process evaluation indicators are determined as the plant electricity consumption, gas turbine natural gas consumption and high-pressure cylinder temperature drop rate. The statistical start time is the unit AGC (Automatic Generation Control) exit time, and the statistical end time is 2 hours after the unit AGC exit time. A shutdown process evaluation method is established.

[0035] Step b1 includes: counting the natural gas consumption F of the gas turbine during the shutdown process shut The gas turbine natural gas consumption score during the shutdown process is S gas-shut :

[0036] S gas-shut =100-K gas-shut ×(F shut -F s ),

[0037] S gas-shut The upper limit is 100, the lower limit is 0, K gas-shut is the natural gas consumption deviation conversion coefficient, F s It is the baseline value of natural gas consumption during the shutdown process, which is obtained from the statistical data of multiple start-up and shutdown processes;

[0038] Statistics of power consumption during shutdown process E shut The gas turbine natural gas consumption score during the shutdown process is S eng-shut :

[0039] S eng-shut =100-K eng-shut ×(E shut -E s ),

[0040] S eng-shut The upper limit is 100, the lower limit is 0, K eng-shut is the power consumption deviation conversion coefficient of the plant, E s It is the base value of the power consumption of the plant during the shutdown process, which is obtained from the statistical data of multiple start-stop processes;

[0041] Statistical average value of high pressure cylinder temperature drop rate during shutdown process T tDownavg The temperature drop rate of the high-pressure cylinder during the shutdown process is rated as S tDown-shut :

[0042] S tDown-shyt =100-K tDown-shut ×(T tDownavg -T s ),

[0043] S tDown-shyt The upper limit is 100, the lower limit is 0, KtDown-shyt is the average deviation conversion coefficient of the high-pressure cylinder temperature drop rate, T s It is the average value of the high-pressure cylinder temperature drop rate, which is obtained from the statistical data of multiple start-stop processes;

[0044] The initial value of the downtime process score is S tem-shut :

[0045] S tem-shut =S gas-shut ×W gas-shut +S eng-shut ×W eng-shut +S gas ×0.2+S tDown-shut ×W tDown-shut .

[0046] W gas-shut is the natural gas consumption score weight coefficient during shutdown process, W eng-shyt is the power consumption weight coefficient of the shutdown process, W tDown-shut It is the scoring weight coefficient of the average value of the temperature drop rate of the high-pressure cylinder during the shutdown process.

[0047] The method of the present invention further comprises:

[0048] Step c1: collect statistics on key indicators of the startup process and display them in the control system:

[0049] Determine the key statistical data of the startup process, including the running time of the circulating water pump, the running time of the medium-pressure feed water pump, the running time of the vacuum pump, the running time of the cooling tower fan, the power consumption of the high-pressure feed water pump, the power consumption of the condensate pump, the gas consumption of the startup furnace, the maximum upper and lower wall temperature difference of the high-pressure drum, the total gas consumption of the gas turbine during the startup process, the time required from the start of the gas turbine to the AGC input of the unit, and the time required from the grid connection of the gas turbine to the AGC input of the unit. The statistical time takes the AGC input of the unit as the end time and the time 5 hours before the AGC input of the unit as the start time:

[0050] Statistics on the running time of the circulating water pump (using the prepared data analysis software to read the running status data of the circulating water pump by second within the statistical time). The circulating water pump is a power frequency running device, and the running time of the circulating water pump is the total running time of all the circulating water pumps of the whole unit within the statistical time;

[0051] Statistics on the running time of medium-pressure feed water pumps. The medium-pressure feed water pumps are power frequency running equipment. The running time of medium-pressure feed water pumps is the total running time of all medium-pressure feed water pumps in the whole unit within the statistical time.

[0052] Statistics on the running time of vacuum pumps. Vacuum pumps are power frequency running equipment. The running time of vacuum pumps is the total running time of all vacuum pumps in the whole unit within the statistical time.

[0053] Statistics on the running time of cooling tower fans. Cooling tower fans are industrial frequency running equipment. The running time of cooling tower fans is the total running time of all cooling tower fans in the whole unit within the statistical time.

[0054] The power consumption of the high-pressure water supply pump is counted. The high-pressure water supply pump is a variable frequency operation device. The power consumption of the high-pressure water supply pump is the total power consumption of all high-pressure water supply pumps of the whole unit during the statistical period.

[0055] Condensate pump power consumption statistics, condensate pump is a variable frequency operation equipment, the condensate pump power consumption is the total power consumption of all condensate pumps in the whole unit during the statistical time;

[0056] The gas consumption of the startup furnace is counted as the cumulative value of the gas consumption of the startup furnace during the statistical period;

[0057] Statistics of the maximum temperature difference between the upper and lower walls of the high-pressure steam drum, which is the maximum value of the maximum temperature difference between the upper and lower walls of the high-pressure steam drum during the statistical time;

[0058] Statistics of total gas consumption of gas turbine during startup process, which is the cumulative value of total gas consumption of gas turbine during statistical time;

[0059] Statistics on the time required from gas turbine startup to unit AGC input, the time from gas turbine startup to unit AGC input;

[0060] Statistics on the time required from the gas turbine being connected to the grid to the AGC being put into operation. Statistics on the time required from the gas turbine being connected to the grid to the AGC being put into operation.

[0061] The method of the present invention further comprises:

[0062] Step d1: collect statistics on the key indicators of the shutdown process and display them in the control system:

[0063] The key data of the shutdown process are counted and displayed in the control system for operators to analyze the shutdown operation during work. The statistical time starts with the unit AGC exit and ends 2 hours after the unit AGC exit. The statistical data includes the high-pressure cylinder temperature drop rate, the total gas consumption of the gas turbine during the shutdown process, the total power consumption of the plant during the shutdown process, the steam turbine run time and the gas turbine run time;

[0064] The temperature drop rate of the high-pressure cylinder is counted to obtain the average temperature drop of the high-pressure cylinder between the start time and the end time of the shutdown;

[0065] The total gas consumption of the gas turbine during the shutdown process is counted to obtain the cumulative value of the gas turbine gas consumption between the shutdown start time and the shutdown end time;

[0066] The total power consumption of the plant during the shutdown process is counted to obtain the cumulative value of the total power consumption of the plant between the start time and the end time of the shutdown;

[0067] Statistics are made on the turbine running time to obtain the time for the turbine to be disconnected and for the turbine speed to reach the cranking speed;

[0068] Statistics are collected on the running time of the gas turbine to obtain the time it takes for the gas turbine to be disconnected and for the speed of the gas turbine to reach the cranking speed.

[0069] The method of the present invention further comprises: evaluating and optimizing the existing start-stop process according to the different start-up processes of the unit, and displaying the optimal start-up process data in the control system, comprising the following steps:

[0070] Summarize the cold start process during the unit start-up and shutdown process to find the optimal cold start process;

[0071] Classify the warm start process during the unit start-up and shutdown process to find the optimal warm start process;

[0072] Classify the hot start process during the unit start-up and shutdown process to find the optimal hot start process;

[0073] Classify the extremely hot start-up process during the start-up and shutdown of the unit to find the optimal start-up process;

[0074] Classify the extremely hot start process during the start and stop process of the unit and find the optimal extremely hot start process;

[0075] The data of the optimal cold start-up process, the optimal warm start-up process, the optimal hot start-up process and the optimal extremely hot start-up process are transmitted to the control system. The data are the statistical data described in 3 for the corresponding process.

[0076] The method of the present invention also includes: evaluating and optimizing the existing start-stop process, and displaying the optimal shutdown process result in the control system, including S tem , S time , S eng , S gas , S makeUpwater , S Tdiv , S V , S gz , S Btup , S tem-shut , S gas-shut , S eng-shut , S gas , S tDown-shut, the operating time of the circulating water pump, the operating time of the medium-pressure feed water pump, the operating time of the vacuum pump, the operating time of the cooling tower fan, the power consumption of the high-pressure feed water pump, the power consumption of the condensate pump, the gas consumption of the startup furnace, the maximum temperature difference between the upper and lower walls of the high-pressure drum, the total gas consumption of the gas turbine during the startup process, the time required from the start-up of the gas turbine to the AGC input of the unit, and the time required from the grid connection of the gas turbine to the AGC input of the unit, the temperature drop rate of the high-pressure cylinder, the total gas consumption of the gas turbine during the shutdown process, the total power consumption of the plant during the shutdown process, the turbine run time, and the gas turbine run time;

[0077] Real-time evaluation of the unit start-up and shutdown process, including:

[0078] According to the actual operating status of the unit, the start-up and shutdown process of the unit is evaluated in real time according to the functional relationship in step a6-2, and the evaluation results and process data are displayed in the control system, including S tem , S time , S eng , S gas , S makeUpwater , S Tdiv , S V , S gz , S Btup , S tem-shut , S gas-shut , S eng-shut , S gas , S tDown-shut , the operating time of the circulating water pump, the operating time of the medium-pressure feed water pump, the operating time of the vacuum pump, the operating time of the cooling tower fan, the power consumption of the high-pressure feed water pump, the power consumption of the condensate pump, the gas consumption of the startup furnace, the maximum temperature difference between the upper and lower walls of the high-pressure drum, the total gas consumption of the gas turbine during the startup process, the time required from the start-up of the gas turbine to the AGC input of the unit, and the time required from the grid connection of the gas turbine to the AGC input of the unit, the temperature drop rate of the high-pressure cylinder, the total gas consumption of the gas turbine during the shutdown process, the total power consumption of the plant during the shutdown process, the turbine run time, and the gas turbine run time;

[0079] When the unit is in shutdown state, the control system displays the evaluation results and process data of the most recent start-stop cycle;

[0080] Achieve automatic update of evaluation systems and data, including:

[0081] After the unit's additional operating time reaches the set time, the functional relationship between the unit expansion and the start-up and shutdown time consumed during the startup process is updated: T = f T (x pz );

[0082] After the additional running time of the unit reaches the set time, the functional relationship between the expansion of the high-pressure cylinder of the turbine during the turbine run-up and the power consumption during the startup process is updated E=f E (x pz );

[0083] After the additional running time of the unit reaches the set time, the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the steam turbine start-up and the amount of natural gas consumed during the startup process is updated G = f G (x pz );

[0084] After the additional running time of the unit reaches the set time, the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the steam turbine start-up and the amount of make-up water consumed during the startup process is updated W = f W (x pz );

[0085] After the automatic update of the unit startup evaluation system is realized, the data displayed in the control system is updated.

[0086] The present invention has the following beneficial effects: the present invention is a method for evaluating the multi-constraint start-up and shutdown process of a combined cycle power generation unit, which can establish a reasonable unit start-up and shutdown evaluation system through data analysis modeling, and push the results to the control system, thereby providing guidance for the continuous optimization of the operating process of the power generation unit operators. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more clear.

[0088] Figure 1 It is a schematic diagram of the unit start-stop score calculation process. DETAILED DESCRIPTION

[0089] According to the equipment configuration described in Table 1, an example is described below based on a typical combined cycle power generation unit.

[0090] Table 1

[0091] Serial number equipment quantity Operational characteristics 1 gas turbine 1 2 Gas turbine generator 1 3 Steam Turbine 1 4 Steam Turbine Generator 1 5 High pressure water pump 2 Frequency conversion operation 6 Medium pressure water pump 2 Power frequency operation 7 Condensate pump 2 Frequency conversion operation 8 Cooling tower fan 5 Power frequency operation 9 Circulation pump 2 Power frequency operation 10 Vacuum Pump 2 Power frequency operation

[0092] like Figure 1 As shown, this embodiment provides a multi-constraint start-stop evaluation system method for a joint generator set, including: establishing a unit start-up process evaluation system:

[0093] (1) Establish data communication with the control system, analyze the start-up and shutdown process of the unit, and determine and collect key data of the start-up and shutdown process of the unit;

[0094] (2) Collect various parameters during the start-up and shutdown process of the combined cycle generator set, including NOx emissions, unit load, SFC status, gas turbine speed, steam turbine speed, expansion of the high-pressure cylinder of the steam turbine during turbine run-up, operating signals of power frequency equipment, drum water level, operating current of frequency conversion equipment, and factory power bus voltage;

[0095] (3) Determine the key nodes in the entire operation cycle from unit start-up to shutdown, including 14 nodes: gas turbine start-up, gas turbine constant speed, gas turbine grid connection, steam turbine run-up, steam turbine constant speed, steam turbine grid connection, unit load exceeding 270MW, unit load below 270MW, steam turbine disconnection, vacuum break, steam turbine idling end, gas turbine disconnection, gas turbine idling end and steam turbine cranking start;

[0096] (4) The start of the gas turbine is used as the starting node of an operation cycle of the entire unit, and these 14 node times are pushed to the control system;

[0097] (5) After the gas turbine and steam turbine are disconnected, the steam turbine cranking motor is started as the end node of an operation cycle of the whole unit;

[0098] (6) Statistics of key indicators during the startup process include plant electricity consumption during the startup process, natural gas consumption of gas turbines during the startup process, and water replenishment during the start-up and shutdown processes;

[0099] (7) When calculating the power consumption of the plant, the end time is the time when the unit AGC is put into operation, and the start time is the time 5 hours before the unit AGC is put into operation;

[0100] (8) When calculating the natural gas consumption of the gas turbine during the startup process, the start time is when the gas turbine starts normally and the speed exceeds 5 rpm, and the end time is when the AGC of the entire unit is put into operation;

[0101] (9) When calculating the amount of water replenishment during the startup process, the start time is when the gas turbine starts normally and the speed exceeds 5 rpm, and the end time is when the AGC of the entire unit is put into operation;

[0102] (10) Analyze the data of the existing startup process, determine the key factors affecting the startup efficiency and safety of the unit startup process, find out the relationship between the factors and the startup process indicators, and establish the startup process evaluation method:

[0103] (11) Analyzing the startup process data of the combined cycle generator set described in Tables 2 to 4, it is determined that the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up is the key factor affecting the startup process of the unit under various conditions;

[0104] Table 2

[0105]

[0106]

[0107]

[0108]

[0109]

[0110] Table 3

[0111]

[0112]

[0113]

[0114]

[0115]

[0116]

[0117] Table 4

[0118]

[0119]

[0120]

[0121]

[0122]

[0123] Table 5 shows the key nodes of the start-up and shutdown process of a combined cycle generator set.

[0124] Table 5

[0125]

[0126]

[0127] Table 6 shows the key parameters of a combined cycle generator set during turbine run-up.

[0128] Table 6

[0129] Serial number content data 1 Temperature of inner cylinder wall after regulating stage (upper half) 493.85 2 Temperature of the inner wall of the cylinder after the adjustment stage (lower half) 474.64 3 Medium pressure steam inlet chamber inner wall metal temperature (upper half) 478.76 4 Medium pressure steam inlet inner wall metal temperature (lower half) 452.8 5 High pressure main steam pressure (preferred) 8.14 6 Medium pressure main steam temperature (optimal) 518.95 7 Medium pressure main steam pressure (preferred) 1.21 8 Medium pressure main steam temperature (optimal) 508.55 9 eccentric 14.91 10 Axis displacement 1# 0.37 11 Axis displacement 2# 0.33 12 Axis displacement 3# 0.22 13 High pressure cylinder thermal expansion left 44.94 14 High pressure cylinder thermal expansion 44.91 15 High pressure cylinder expansion difference -0.1 16 Low pressure cylinder expansion difference -0.5 17 Condenser vacuum 8.79 18 Jacking oil pipe pressure 17.66 19 Lubricating oil pressure 0.19 20 Lubricating oil cooler outlet oil temperature (oil tank) 38.07

[0130] Table 7 shows the statistical data of the start-up and shutdown process of a combined cycle generator set.

[0131] Table 7

[0132] Serial number content data 1 Circulation pump running time during startup 104.767 2 Running time of feed water pump during startup 104.767 3 Vacuum pump running time during startup 104.767 4 Cooling tower fan running time during startup 83.383 5 Power consumption of high pressure water supply pump during startup 1371.12 6 Power consumption of condensate pump during startup 531.5 7 Temperature difference between upper and lower walls of high pressure drum during startup 26.92 8 Temperature difference between inner and outer walls of high pressure steam drum during startup 17.99 9 Time required from gas turbine grid connection to AGC commissioning 72.717 10 Gas consumption during startup 57096.94 11 Time from gas turbine startup to AGC input 104.75 12 Condenser water replenishment during startup 15.48 13 Power consumption of the plant in the first 5 hours after AGC is put into use 17470.96 14 The temperature difference between the upper and lower walls of the high-pressure steam drum during the startup process is 40-50 seconds. 0 15 The temperature difference between the upper and lower walls of the high-pressure steam drum during the startup process is 50-60°C. 0 16 The temperature difference between the upper and lower walls of the high-pressure steam drum during the startup process is 60+ seconds 0 17 The vacuum time during startup exceeds 16 seconds 0 18 The cylinder expansion during startup lasts for more than 10.5 seconds 0 19 Average temperature drop rate of the high-pressure cylinder on the machine side during shutdown 0.94 20 Gas consumption during shutdown 29989.76 21 Power consumption during shutdown 7480.16 22 The length of turbine idling time during shutdown 55.067 23 The engine idling time during shutdown 26.883

[0133] (12) Determine the functional relationship between the expansion of the high-pressure cylinder of the turbine during the turbine run-up and the start-up time T = -239 × ln (x pz )+1013.6,x pz The high pressure cylinder of the steam turbine expands when the turbine is running;

[0134] (13) Determine the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the start-up and the power consumption during the start-up and shutdown process E = -6159 × ln (x pz )+41541;

[0135] (14) Determine the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up and the natural gas consumption of the gas turbine during the start-up and shutdown process G = -100000 × ln (x pz )+439871);

[0136] (15) Determine the functional relationship between the expansion of the high-pressure cylinder of the turbine during the turbine run-up and the amount of make-up water consumed during the start-up and shutdown process W = -0.8836 × x pz +54.213;

[0137] (16) 20% of the startup process is restricted by the power grid and equipment, and the startup process cannot be carried out according to the normal startup process, S = 80;

[0138] (17) Based on the existing actual startup process data and the relationship determined by (13) to (15), the data in Tables 2 to 4 are used to calculate the deviations between the theoretical startup time, theoretical plant power consumption, theoretical gas turbine natural gas consumption and water replenishment during the startup process and the actual values, and determine K T =0.251, K E =0.00284, K G =0.000231, K W =0.354.

[0139] (18) According to the expansion of the high-pressure cylinder of the steam turbine during the actual turbine run-up, the theoretical start-stop time T under the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up is calculated. target , count the time T consumed in the actual start-stop process actual , startup process time score S time =80-(T actual -T target )×0.25,S time The maximum value is 100 and the minimum value is 0.

[0140] (19) According to the expansion of the high-pressure cylinder of the steam turbine during the actual turbine start-up, calculate the theoretical plant power consumption E under the expansion of the high-pressure cylinder of the steam turbine during the turbine start-up target , calculate the actual power consumption E during the start-stop process actual , plant power consumption score S eng =80-(E actual -E target )×0.00284,S eng The maximum value is 100 and the minimum value is 0.

[0141] (20) According to the expansion of the high-pressure cylinder of the steam turbine during the actual turbine start-up, calculate the theoretical natural gas consumption G under the expansion of the high-pressure cylinder of the steam turbine during the turbine start-up target , calculate the natural gas consumption during the actual start-stop process G actual , natural gas consumption score S gas =80-(G actual -G targrt )×0.000231,S gas The maximum value is 100 and the minimum value is 0.

[0142] (21) According to the expansion of the high-pressure cylinder of the steam turbine during the actual turbine run-up, calculate the water replenishment amount W under the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up target , calculate the actual amount of water consumed during the start-stop process W actual , water replenishment score S makeUpwater =80-(W actual -W target )×0.354,S makeUpwater The maximum value is 100 and the minimum value is 0.

[0143] (22) The start-up time is taken as the cost of consuming the unit life, the cost of plant power consumption, the cost of gas turbine natural gas consumption and the cost of condenser water replenishment as the total cost. The total cost of the unit is calculated and the weights of the start-up time, plant power consumption, gas turbine natural gas consumption and condenser water replenishment on the unit start-up are analyzed. Considering that the water replenishment is a controllable factor, the weight is magnified and the start-up time, plant power consumption and gas turbine natural gas consumption are proportionally reduced to obtain W. time =0.5,W eng =0.2,W gas =0.2,W water =0.1

[0144] (22) The initial value of the startup process score is S tem =S time ×0.5+S eng ×0.2+S gas ×0.2+S makeUpwater ×0.1,S tem =80.5

[0145] Table 7 shows the calculation results of the startup process score.

[0146] Table 7

[0147]

[0148]

[0149] (18) The data of the existing startup process is analyzed to determine that the key indicators that affect the safety of unit operation are the temperature difference between the upper and lower walls of the drum, vacuum, cylinder expansion and boiler temperature rise rate. Any of the indicators exceeding the limit will affect the safe startup of the unit. The statistical start time is when the gas turbine starts normally and the speed exceeds 5 rpm, and the statistical end time is when the AGC of the entire unit is put into use. These parameters of the start-stop process are statistically analyzed to further complete the startup process evaluation method;

[0150] (19) Count the time when the temperature difference between the upper and lower walls of the high-pressure steam drum is in different ranges by minute, and the time T between 40℃ and 50℃ 40-50 The time T when the temperature difference between the upper and lower walls of the high-pressure steam drum is between 40℃ and 50℃ 50-60 The time T when the temperature difference between the upper and lower walls of the high-pressure steam drum is between 40℃ and 50℃ 60- The temperature difference between the upper and lower walls of the high-pressure steam drum is S Tdiv , S Tdiv =T 40-50 ×1.5+T 50-60 ×1+T 50- ×2;

[0151] (20) Count the time T in which the condenser vacuum exceeds 16 kPa in minutes 16- , condenser vacuum deduction S V , S V =T 16- ×1;S V =0

[0152] (21) The time T when the turbine cylinder expansion exceeds 10.5 mm is counted in minutes 10.5- , steam turbine cylinder expansion deduction item S gz , S gz =T 10.5- ×2;S gz =0

[0153] (22) Statistical average boiler temperature rise rate T tUpavg , boiler temperature rise rate deduction item S Btup , S Btup =(T tUpavg -5)×5; S Btup =0

[0154] Table 8 shows the calculation results of the deduction items for the startup process score.

[0155] Table 8

[0156] project Statistical indicators Statistics Deduction value The temperature difference between the upper and lower walls of the high-pressure steam drum during the startup process is 40-50 seconds. T_(40-50) 0 0.000000 The temperature difference between the upper and lower walls of the high-pressure steam drum during the startup process is 50-60°C. T_(50-60) 0 0.000000 The temperature difference between the upper and lower walls of the high-pressure steam drum during the startup process is 60+ seconds T_(60-) 0 0.000000 The vacuum time during startup exceeds 16 seconds T_(16-) 0 0.000000 The cylinder expansion during startup lasts for more than 10.5 seconds T_(10.5-) 0 0.000000

[0157] (23) The total score of the startup process is S see , S see =S tem -STdiv -S V -S gz -S Btup . S see =80.5 The method of the embodiment of the present invention further includes: establishing a unit shutdown process evaluation system:

[0158] (1) The shutdown process evaluation indicators are determined as the plant power consumption, gas turbine natural gas consumption and high-pressure cylinder temperature drop rate. The statistical start time is the unit AGC exit time, and the statistical end time is 2 hours after the unit AGC exit time. The shutdown process evaluation method is established:

[0159] (2) Statistics of natural gas consumption of gas turbines during shutdown process F shut , gas turbine natural gas consumption score S during shutdown gas-shut , S gas-shut =100-0.02×(F shut -15000), S gas-shut The upper limit is 100 and the lower limit is 0.

[0160] (3) Statistical analysis of power consumption during shutdown E shut , gas turbine natural gas consumption score S during shutdown eng-shut , S eng-shut =100-0.02×(E shut -9000), S eng-shut The upper limit is 100 and the lower limit is 0.

[0161] (4) Statistical average temperature drop rate of high-pressure cylinder during shutdown process T tDownavg , gas turbine natural gas consumption score S during shutdown tDown-shut , S tDown-shut =100-333.33×(T tDownavg -1), S tDown-shut The upper limit is 100 and the lower limit is 0.

[0162] (5) According to the data in Table 9, the downtime process score is S tem-shut , S tem-shut =S gas-shut ×0.35+S eng-shut ×0.2+S gas ×0.2+S tDown-shut ×0.45;S tem-shut =60;

[0163] Table 9 shows the calculation results of the shutdown process score.

[0164] Table 9

[0165] project Statistics Calculate the score Actual score Gas consumption during shutdown 29989.76 -199.795200 0.000000 Power consumption during shutdown 7480.16 130.396800 100.000000 Average temperature drop rate of the high-pressure cylinder on the machine side during shutdown 0.94 119.999800 100.000000 Total score 65.000000

[0166] 1. Collect statistics on key indicators of the startup process and display them in the control system:

[0167] (1) Determine the key statistical data of the startup process, including the running time of the circulating water pump, the running time of the medium-pressure feed water pump, the running time of the vacuum pump, the running time of the cooling tower fan, the power consumption of the high-pressure feed water pump, the power consumption of the condensate pump, the gas consumption of the startup furnace, the maximum temperature difference between the upper and lower walls of the high-pressure drum, the total gas consumption of the gas turbine during the startup process, the time required from the start of the gas turbine to the AGC input of the unit, and the time required from the grid connection of the gas turbine to the AGC input of the unit. The statistical time takes the AGC input of the unit as the end time and the time 5 hours before the AGC input of the unit as the start time:

[0168] (2) Statistics on the running time of the circulating water pump. The circulating water pump is a power frequency operating device. The running time of the circulating water pump is the total running time of all the circulating water pumps of the whole unit within the statistical time;

[0169] (3) Statistics on the running time of the medium-pressure feedwater pump. The medium-pressure feedwater pump is a power frequency operating device. The running time of the medium-pressure feedwater pump is the total running time of all the medium-pressure feedwater pumps of the whole unit within the statistical time;

[0170] (4) Statistics on the operating time of the vacuum pump. The vacuum pump is a power frequency operating device. The operating time of the vacuum pump is the total operating time of all vacuum pumps in the whole unit within the statistical time;

[0171] (5) Statistics on the running time of cooling tower fans. Cooling tower fans are industrial frequency operating equipment. The running time of cooling tower fans is the total running time of all cooling tower fans in the whole unit during the statistical time;

[0172] (6) Statistics on the power consumption of high-pressure water supply pumps. The high-pressure water supply pumps are variable frequency operation equipment. The power consumption of high-pressure water supply pumps is the total power consumption of all high-pressure water supply pumps of the whole unit during the statistical period;

[0173] (7) Statistics on the power consumption of the condensate pump. The condensate pump is a variable frequency operation device. The power consumption of the condensate pump is the total power consumption of all condensate pumps in the whole unit during the statistical period;

[0174] (8) Statistics on gas consumption of the startup furnace, which is the cumulative value of gas consumption of the startup furnace during the statistical period;

[0175] (9) Statistics on the maximum temperature difference between the upper and lower walls of the high-pressure steam drum, which is the maximum value of the maximum temperature difference between the upper and lower walls of the high-pressure steam drum during the statistical period;

[0176] (10) Statistics of the total gas consumption of the gas turbine during the startup process, which is the cumulative value of the total gas consumption of the gas turbine during the statistical period;

[0177] (11) Statistics on the time required from gas turbine startup to unit AGC input, the time required from gas turbine startup to unit AGC input;

[0178] (12) Statistics on the time required from the connection of the gas turbine to the grid to the start of the AGC operation of the unit.

[0179] 2. The key indicators of the shutdown process are counted and displayed in the control system to facilitate the operation personnel to analyze the shutdown operation during work. The statistical time starts with the unit AGC exit and ends 2 hours after the unit AGC exit. The statistical data includes the high-pressure cylinder temperature drop rate, the total gas consumption of the gas turbine during the shutdown process, the total plant electricity consumption during the shutdown process, the steam turbine running time and the gas turbine running time.

[0180] (1) The temperature drop rate of the high-pressure cylinder is counted to obtain the average temperature drop of the high-pressure cylinder between the start time and the end time of the shutdown;

[0181] (2) Counting the total gas consumption of the gas turbine during the shutdown process to obtain the cumulative gas consumption value of the gas turbine between the shutdown start time and the shutdown end time;

[0182] (3) Count the total power consumption of the plant during the shutdown process and obtain the cumulative value of the total power consumption of the plant between the start time and the end time of the shutdown;

[0183] (4) Statistic the turbine running time to obtain the time for the turbine to be disconnected and the time for the turbine speed to reach the cranking speed;

[0184] (5) Statistic the engine running time to obtain the time for the engine to be disconnected and the time for the engine speed to reach the cranking speed; 3. According to the methods and processes described in 1 and 2, evaluate the existing start-stop process according to the different unit start-up processes, and display the optimal start-up process data in the control system, and follow the following steps:

[0185] (1) Summarize the cold start process during the unit start-up and shutdown process to find the optimal cold start process;

[0186] (2) Classify the warm start process during the unit start-up and shutdown process to find the optimal warm start process;

[0187] (3) Classify the hot start process during the unit start-up and shutdown process to find the optimal hot start process;

[0188] (4) Classify the extremely hot start-up process during the start-up and shutdown of the unit to find the optimal start-up process;

[0189] (5) Classify the extremely hot start process during the start-up and shutdown process of the unit and find the optimal extremely hot start process;

[0190] (6) The data of the optimal cold start process, the optimal warm start process, the optimal hot start process and the optimal extremely hot start process are transmitted to the control system, and the data are the statistical data described in 3 for the corresponding process.

[0191] 4. According to the methods and steps described in 1 and 2, the existing start-stop process is evaluated and optimized, and the optimal shutdown process results are displayed in the control system. The data is the corresponding process including the statistical data described in 4.

[0192] 5. According to the methods and processes described in 1 and 2, evaluate the start-up and shutdown process of the unit in real time:

[0193] (1) According to the actual operating status of the unit, the start-up and shutdown process of the unit is evaluated in real time, and the evaluation results and process data are displayed in the control system, including the data described in 3 and 4.

[0194] (2) When the unit is in shutdown state, the control system displays the evaluation results and process data of the most recent start-stop cycle.

[0195] 6. According to the methods and projects described in 1 and 2, the evaluation system and data are automatically updated:

[0196] (1) After the unit's additional operating time reaches the set time, the functional relationship between the unit expansion and the start-up and shutdown time consumed during the startup process is updated: T = f T (x pz );

[0197] (2) After the additional running time of the unit reaches the set time, the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the start-up and the power consumption during the startup process is updated. E = f E (x pz );

[0198] (3) After the additional running time of the unit reaches the set time, the functional relationship between the expansion of the high-pressure cylinder of the turbine during the turbine start-up and the amount of natural gas consumed during the startup process is updated G = f G (x pz );

[0199] (4) After the additional running time of the unit reaches the set time, the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the steam turbine start-up and the amount of make-up water consumed during the startup process is updated W = f G (x pz );

[0200] (5) After the automatic update of the unit startup evaluation system is realized, the methods and steps described in 3, 4, 5 and 6 are used to update the data displayed in the control system.

Claims

1. A method for evaluating the multi-constraint start-stop process of a combined cycle power generation unit, characterized in that: include: By analyzing the start-up and shutdown process data of the combined cycle generator set, a data model between key parameters of the start-up and shutdown process is established, and then a unit start-up process evaluation system and a unit shutdown process evaluation system are established. The establishment of the unit start-up process evaluation system includes the following steps: Step a1, establish data communication with the control system, obtain and store the unit operation data from the control system database, analyze the unit start-stop process, including analyzing the start-stop initial state, start-stop time, start-stop process energy consumption and safety restriction conditions, and determine the key data affecting the unit start-stop process, the key data includes the engine speed, the engine generator active power, the unit AGC input state, the engine consumption natural gas flow, the turbine high pressure cylinder expansion and water replenishment during the turbine start-up; Step a2, determining the key nodes in the entire operation cycle of the unit from start to stop according to the unit operation procedures and the operation status of key equipment; the operation status of key equipment includes the gas turbine speed, gas turbine generator grid connection, steam turbine speed, steam turbine generator grid connection and AGC input status; Step a3, taking the start of the gas turbine as the starting node of an operation cycle of the whole unit; Step a4, after the gas turbine and the steam turbine are disconnected, the steam turbine cranking motor is started as the end node of one operation cycle of the whole unit; Step a5, determining statistics of key indicators of the startup process, wherein the key indicators include the amount of plant electricity consumed during the startup process, the natural gas consumption of the gas turbine during the startup process, and the amount of makeup water consumed during the startup process; Step a6, considering the startup efficiency and the safety of the startup process, analyzing the data of the existing startup process, determining the key factors affecting the unit startup process, finding out the relationship between the key factors and the startup process indicators, and establishing a startup process evaluation method; Step a7, according to the existing startup process, data analysis and unit operation procedure requirements are performed to determine that the key indicators affecting the unit operation safety are the upper and lower wall temperatures of the drum, vacuum, cylinder expansion and boiler temperature rise rate, and the normal startup of the gas turbine and the speed exceeding the threshold are the statistical start time; Step a8, taking the time when the load of the entire unit exceeds the threshold and the AGC is put into operation as the statistical end time, statistical analysis is performed on the parameters of the startup process to further complete the startup process evaluation method, and the evaluation process can be designed according to the power plant operation requirements.

2. The method according to claim 1, characterized in that: In step a5, when the power consumption of the plant during the startup process is counted, the start time and end time of the power consumption statistics are determined according to the operating characteristics of the unit; When counting the natural gas consumption of the gas turbine during the startup process, the starting time of the natural gas consumption of the gas turbine is determined according to the start time of the gas consumption during the startup process of the gas turbine, and the end time is when the load of the entire unit exceeds the threshold and the AGC is put into operation; When counting the amount of make-up water consumed during the start-stop process, the start and end times of the statistics on the amount of make-up water consumed during the start-stop process are determined based on the operating characteristics of the unit.

3. The method according to claim 2, characterized in that Step a6 includes: Step a6-1, analyzing the startup process of the combined cycle generator set and combining it with the requirements of the operating procedures, determining that the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up is the key factor affecting the startup process of the unit under various states; Step a6-2, analyze and model the startup data to determine the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up and the time consumed in the startup process T = f T (x pz 0, determine the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the start-up and the power consumption during the startup process E = f E (x pz ), determine the functional relationship between the expansion of the high-pressure cylinder of the turbine during the turbine run-up and the amount of natural gas consumed during the startup process G = f G (x pz ), determine the functional relationship between the expansion of the high-pressure cylinder of the turbine during the turbine run-up and the amount of make-up water consumed during the start-up process W = f W (x pz ), T is the unit startup process time, E is the power consumption during the startup process, G is the natural gas volume during the startup process, W is the water replenishment volume during the startup process, x pz The high pressure cylinder of the steam turbine expands when the turbine is running; Step a6-3, based on the expansion of the high-pressure cylinder of the steam turbine during the actual turbine run-up, use T=f obtained in step a6-2 T (x pz ) function relationship, calculate the theoretical start-stop time T under the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up target , count the time T consumed in the actual start-stop process actual , startup process time score S time =S-(T actual -T target )×K T , K T is the time deviation coefficient of the startup process, S is the score benchmark value; Step a6-4, based on the expansion of the high-pressure cylinder of the steam turbine during the actual turbine run-up, use E=f obtained in step a6-2 E (x pz ) function relationship, calculate the theoretical plant power consumption E under the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up target , calculate the actual power consumption E during the start-stop process actual , plant power consumption score S eng The calculation process is S eng =S-(E actual -E target )×K E , K E is the deviation coefficient of plant power consumption; Step a6-5, based on the expansion of the high-pressure cylinder of the steam turbine during the actual turbine run-up, use G=f obtained in step a6-2 G (x pz ) function relationship, calculate the theoretical natural gas consumption G under the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up target , calculate the natural gas consumption during the actual start-stop process G actual , natural gas consumption score S gas The calculation process is S gas =S-(G actual -G target )×K G , K G is the natural gas consumption deviation coefficient; Step a6-6, based on the expansion of the high-pressure cylinder of the steam turbine during the actual turbine run-up, use W=f obtained in step a6-2 W (x pz ) function relationship, calculate the water replenishment amount W under the expansion of the high-pressure cylinder of the steam turbine during the turbine run-up target , calculate the actual amount of water consumed during the start-stop process W actual , water replenishment score S makeUpwater =S-(W actual -W target )×K E , K W is the water replenishment deviation coefficient; Step a6-7, start process scoring initial value S tem for: S tem =S time ×W time +S eng ×W eng +S gas ×W gas +S makeUpwater ×W water , Among them, W time is the weight of the startup time score in the startup process evaluation, W eng is the weight of the power consumption score in the startup process evaluation, W gas is the weight of the gas turbine natural gas consumption score in the startup process evaluation, W water is the weight of the water replenishment score in the startup process evaluation, and the weight is obtained based on the correlation analysis of the existing start-stop data.

4. The method according to claim 3, characterized in that Step a7 includes: according to the unit operation management regulations and the unit equipment safety operation requirements, statistics are collected on the upper and lower wall temperatures of the drum, vacuum, cylinder expansion and boiler temperature rise rate data, and the time when the upper and lower wall temperature difference of the high-pressure drum is in different ranges is counted by minute, and the time T between 40℃ and 50℃ is counted. 40-50 The time T when the temperature difference between the upper and lower walls of the high-pressure drum is between 40℃ and 50℃ 50-60 The time T when the temperature difference between the upper and lower walls of the high-pressure drum is between 40℃ and 50℃ 60- The temperature difference between the upper and lower walls of the high-pressure steam drum is S Tdiv ; The time that the condenser vacuum exceeds the safe operation limit is counted in minutes, and recorded as T 16- , condenser vacuum deduction S V ; The time when the steam turbine cylinder expansion exceeds the safe operation limit is counted in minutes, and recorded as T 9.5- , the deduction item for steam turbine cylinder expansion is S gz ; Statistical average boiler temperature rise rate T tUpavg , the boiler temperature rise rate deduction item is S Btup ; The overall rating for the startup process is S see : S see =S tem -S rdiv -S V -S gz -S Btup 。 5. The method according to claim 4, characterized in that The establishment of the unit shutdown process evaluation system comprises the following steps: Step b1, since the shutdown process is restricted by equipment and power grid requirements, the shutdown process evaluation system is carried out according to the actual situation of the power plant, and the shutdown process evaluation indicators are determined as the plant electricity consumption, gas turbine natural gas consumption and high-pressure cylinder temperature drop rate. The statistical start time is the unit AGC exit time, and the unit AGC exit a certain time as the statistical end time, and a shutdown process evaluation method is established.

6. The method according to claim 5, characterized in that Step b1 includes: counting the natural gas consumption F of the gas turbine during the shutdown process shut The gas turbine natural gas consumption score during the shutdown process is S gas-shut : S gas-shut =100-K gas-shut ×(F shut -F s ), S gas-shut The upper limit is 100, the lower limit is 0, K gas-shut is the natural gas consumption deviation conversion coefficient, F s It is the baseline value of natural gas consumption during the shutdown process, which is obtained from the statistical data of multiple start-up and shutdown processes; Statistics of power consumption during shutdown process E shut The gas turbine natural gas consumption score during the shutdown process is S eng-shut : S eng-shut =100-K eng-shut ×(E shut -E s ), S eng-shut The upper limit is 100, the lower limit is 0, K eng-shut is the power consumption deviation conversion coefficient of the plant, E s It is the base value of the power consumption of the plant during the shutdown process, which is obtained from the statistical data of multiple start-stop processes; Statistical average value of high pressure cylinder temperature drop rate during shutdown process T tDownavg The temperature drop rate of the high-pressure cylinder during the shutdown process is rated as S tDown-s h ut : S tDown-shut =100-K tDown-shut ×(T tDownavg -T s ), K tDown-shut is the average deviation conversion coefficient of the high-pressure cylinder temperature drop rate, T s It is the average reference value of the temperature drop rate of the high-pressure cylinder; The initial value of the downtime process score is S tem-shut : S tem-shut =S gas-shut ×W gas-shut +S eng-shut ×W eng-shut +S gas ×0.2+S tDown-shut ×W tDown-shut ; W gas-shut is the natural gas consumption score weight coefficient during shutdown process, W eng-shut is the power consumption weight coefficient of the shutdown process, W tDown-shut It is the scoring weight coefficient of the average value of the temperature drop rate of the high-pressure cylinder during the shutdown process.

7. The method according to claim 6, characterized in that Also includes: Step c1: collect statistics on key indicators of the startup process and display them in the control system: Determine the key statistical data of the startup process, including the running time of the circulating water pump, the running time of the medium-pressure feed water pump, the running time of the vacuum pump, the running time of the cooling tower fan, the power consumption of the high-pressure feed water pump, the power consumption of the condensate pump, the gas consumption of the startup furnace, the maximum upper and lower wall temperature difference of the high-pressure drum, the total gas consumption of the gas turbine during the startup process, the time required from the start of the gas turbine to the AGC input of the unit, and the time required from the grid connection of the gas turbine to the AGC input of the unit. The statistical time takes the AGC input of the unit as the end time and the time 5 hours before the AGC input of the unit as the start time: Statistics on the running time of the circulating water pump. The circulating water pump is a power frequency operating device. The running time of the circulating water pump is the total running time of all the circulating water pumps of the whole unit within the statistical time. Statistics on the running time of medium-pressure feed water pumps. The medium-pressure feed water pumps are power frequency running equipment. The running time of medium-pressure feed water pumps is the total running time of all medium-pressure feed water pumps in the whole unit within the statistical time. Statistics on the running time of vacuum pumps. Vacuum pumps are power frequency running equipment. The running time of vacuum pumps is the total running time of all vacuum pumps in the whole unit within the statistical time. Statistics on the running time of cooling tower fans. Cooling tower fans are industrial frequency running equipment. The running time of cooling tower fans is the total running time of all cooling tower fans in the whole unit within the statistical time. The power consumption of the high-pressure water supply pump is counted. The high-pressure water supply pump is a variable frequency operation device. The power consumption of the high-pressure water supply pump is the total power consumption of all high-pressure water supply pumps of the whole unit during the statistical period. Condensate pump power consumption statistics, condensate pump is a variable frequency operation equipment, the condensate pump power consumption is the total power consumption of all condensate pumps in the whole unit during the statistical time; The gas consumption of the startup furnace is counted as the cumulative value of the gas consumption of the startup furnace during the statistical period; Statistics of the maximum temperature difference between the upper and lower walls of the high-pressure steam drum, which is the maximum value of the maximum temperature difference between the upper and lower walls of the high-pressure steam drum during the statistical time; Statistics of total gas consumption of gas turbine during startup process, which is the cumulative value of total gas consumption of gas turbine during statistical time; Statistics on the time required from gas turbine startup to unit AGC input, the time from gas turbine startup to unit AGC input; Statistics on the time required from the gas turbine being connected to the grid to the AGC being put into operation. Statistics on the time required from the gas turbine being connected to the grid to the AGC being put into operation.

8. The method according to claim 7, characterized in that Also includes: Step d1: collect statistics on the key indicators of the shutdown process and display them in the control system: The key data of the shutdown process are counted and displayed in the control system for operators to analyze the shutdown operation during work. The statistical time starts with the unit AGC exit and ends 2 hours after the unit AGC exit. The statistical data includes the high-pressure cylinder temperature drop rate, the total gas consumption of the gas turbine during the shutdown process, the total power consumption of the plant during the shutdown process, the steam turbine run time and the gas turbine run time; The temperature drop rate of the high-pressure cylinder is counted to obtain the average temperature drop of the high-pressure cylinder between the start time and the end time of the shutdown; The total gas consumption of the gas turbine during the shutdown process is counted to obtain the cumulative value of the gas turbine gas consumption between the shutdown start time and the shutdown end time; The total power consumption of the plant during the shutdown process is counted to obtain the cumulative value of the total power consumption of the plant between the start time and the end time of the shutdown; Statistics are made on the turbine running time to obtain the time for the turbine to be disconnected and for the turbine speed to reach the cranking speed; Statistics are collected on the running time of the gas turbine to obtain the time it takes for the gas turbine to be disconnected and for the speed of the gas turbine to reach the cranking speed.

9. The method according to claim 8, characterized in that Also includes: According to the different startup processes of the unit, the existing start-up and shutdown processes are evaluated and optimized, and the optimal startup process data is displayed in the control system, including the following steps: Summarize the cold start process during the unit start-up and shutdown process to find the optimal cold start process; Classify the warm start process during the unit start-up and shutdown process to find the optimal warm start process; Classify the hot start process during the unit start-up and shutdown process to find the optimal hot start process; Classify the extremely hot start-up process during the start-up and shutdown of the unit to find the optimal start-up process; Classify the extremely hot start process during the start and stop process of the unit and find the optimal extremely hot start process; The data of the optimal cold start-up process, the optimal warm start-up process, the optimal hot start-up process and the optimal extremely hot start-up process are transmitted to the control system. The data are the statistical data described in 3 for the corresponding process.

10. The method according to claim 9, characterized in that Also includes: Evaluate and optimize the existing start-stop process, and display the optimal shutdown process results in the control system, including S tem , S time , S eng , S gas , S makeUpwater , S Tdiv , S V , S gz , S Btup , S tem-shut , S gas-shut , S eng-shut , S gas , S tDown-shut , the operating time of the circulating water pump, the operating time of the medium-pressure feed water pump, the operating time of the vacuum pump, the operating time of the cooling tower fan, the power consumption of the high-pressure feed water pump, the power consumption of the condensate pump, the gas consumption of the startup furnace, the maximum temperature difference between the upper and lower walls of the high-pressure drum, the total gas consumption of the gas turbine during the startup process, the time required from the start-up of the gas turbine to the AGC input of the unit, and the time required from the grid connection of the gas turbine to the AGC input of the unit, the temperature drop rate of the high-pressure cylinder, the total gas consumption of the gas turbine during the shutdown process, the total power consumption of the plant during the shutdown process, the turbine run time, and the gas turbine run time; Real-time evaluation of the unit start-up and shutdown process, including: According to the actual operating status of the unit, the start-up and shutdown process of the unit is evaluated in real time according to the functional relationship in step a6-2, and the evaluation results and process data are displayed in the control system, including S tem , S time , S eng , S gas , S makeUpwater , S Tdiv , S V , S gz , S Btup , S tem-shut , S gas-shut , S eng-shut , S gas , S tDown-shut , the operating time of the circulating water pump, the operating time of the medium-pressure feed water pump, the operating time of the vacuum pump, the operating time of the cooling tower fan, the power consumption of the high-pressure feed water pump, the power consumption of the condensate pump, the gas consumption of the startup furnace, the maximum temperature difference between the upper and lower walls of the high-pressure drum, the total gas consumption of the gas turbine during the startup process, the time required from the start-up of the gas turbine to the AGC input of the unit, and the time required from the grid connection of the gas turbine to the AGC input of the unit, the temperature drop rate of the high-pressure cylinder, the total gas consumption of the gas turbine during the shutdown process, the total power consumption of the plant during the shutdown process, the turbine run time, and the gas turbine run time; When the unit is in shutdown state, the control system displays the evaluation results and process data of the most recent start-stop cycle; Achieve automatic update of evaluation systems and data, including: After the unit's additional operating time reaches the set time, the functional relationship between the unit expansion and the start-up and shutdown time consumed during the startup process is updated: T = f T (x pz ); After the additional running time of the unit reaches the set time, the functional relationship between the expansion of the high-pressure cylinder of the turbine during the turbine run-up and the power consumption during the startup process is updated E=f E (x pz ); After the additional running time of the unit reaches the set time, the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the steam turbine start-up and the amount of natural gas consumed during the startup process is updated G = f G (x pz ); After the additional running time of the unit reaches the set time, the functional relationship between the expansion of the high-pressure cylinder of the steam turbine during the steam turbine start-up and the amount of make-up water consumed during the startup process is updated W = f W (x pz ); After the automatic update of the unit startup evaluation system is realized, the data displayed in the control system is updated.

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