Method and system for adjusting sliding pressure curve of heating unit

Abstract

A method and system for adjusting a sliding pressure curve of a heating unit. The method comprises: collecting steam extraction parameters, and determining steam extraction point positions; performing merged calculation on similar steam extraction points, and calculating work performed by steam from each steam extraction point to turbine exhaust; calculating the total theoretical work of steam extraction, calculating an electricity-to-heat conversion coefficient, and correcting a sliding pressure curve; and performing fuzzy logic control to optimize the sliding pressure curve, determining a load state, and guiding the operation of the unit. The beneficial effect of the present invention is that the sliding pressure curve changes along with the change of the steam supply amount of the unit, so as to guide the operation of the unit. The method is simple to implement and facilitates thermal control and editing; on the one hand, the heat consumption of power plant operation is reduced, thereby maintaining the overall thermal economy of the plant in an optimal state; and on the other hand, editing of logic control is facilitated, thereby improving the level of automation of the power plant.

Description

A method and system for adjusting the sliding pressure curve of a heating unit Technical Field

[0001] This invention relates to the field of steam turbine energy-saving technology, specifically to a method and system for adjusting the sliding pressure curve of a heating unit. Background Technology

[0002] Given increasingly severe energy constraints and economic development challenges, tapping the energy-saving potential of coal-fired power units and optimizing operating parameters are inevitable choices for power plant energy conservation and consumption reduction. Sliding pressure optimization is a common method for optimizing power plant steam turbines. Its main purpose is to ensure the economy and efficiency of operation under different electrical load conditions by adjusting the main steam pressure of the turbine. The sliding pressure curve is generally provided by the turbine manufacturer or obtained through experimental measurement.

[0003] In recent years, with the popularization of combined heat and power (CHP) technology, steam extracted from a certain stage of a steam turbine is frequently used for industrial steam supply and heating. The steam supply varies depending on changes in user and heating demands, making traditional fixed sliding pressure curves ineffective in adapting to these changes. CHP units require frequent adjustments to the steam supply during operation to meet demands under different operating conditions. In the context of deep CHP, steam extracted from a certain stage of a steam turbine is frequently used for both industrial and heating purposes, and the steam supply often changes with user and heating demands. Using a fixed sliding pressure curve cannot guarantee the accuracy of the optimized sliding pressure point for CHP units; the optimized sliding pressure point should change with the change in steam supply.

[0004] Traditional sliding pressure curves are fixed curves and cannot dynamically reflect the impact of steam supply changes on unit operation, resulting in poor optimization effects in actual operation. Fixed sliding pressure curves cannot be adjusted according to real-time changes in steam supply and electrical load, thus failing to achieve optimal energy-saving effects. The steam supply of combined heat and power (CHP) units frequently changes, and fixed sliding pressure curves cannot adapt to these changes, causing the main steam pressure and unit efficiency to deviate from their optimal state.

[0005] Summary of the Invention

[0006] In view of the above-mentioned problems, the present invention is proposed.

[0007] Therefore, the technical problem solved by this invention is: how to modify the original sliding pressure curve by adjusting the steam supply location and steam supply amount, so that it can be adjusted in real time according to the changes in steam extraction and heating from the steam turbine.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for adjusting the sliding pressure curve of a heating unit, comprising:

[0009] Collect extraction parameters to determine extraction points;

[0010] The similar steam extraction points are combined to calculate the steam work from the steam extraction point to the steam turbine exhaust;

[0011] The total of all steam extraction theoretical work is calculated to obtain the electric-thermal conversion coefficient and correct the sliding pressure curve;

[0012] The fuzzy logic control is performed to optimize the sliding pressure curve, judge the load state and guide the unit operation.

[0013] As a preferred scheme of the method for adjusting the sliding pressure curve of the heating unit, the steam extraction parameters include steam supply G, steam extraction pressure p i , the current cold re-pressurization pressure p G , the hot re-pressurization pressure p RH , the medium-pressure cylinder exhaust pressure p I , and the electric power N.

[0014] As a preferred scheme of the method for adjusting the sliding pressure curve of the heating unit, the steam extraction point position includes the high-pressure cylinder certain stage extraction position, the cold re-heater, the hot re-heater, the medium-pressure cylinder certain stage extraction position, and the medium-pressure cylinder exhaust position; the steam extraction point position is determined according to the steam extraction parameters, and there are multiple external steam supply points;

[0015] If p i >1.1p G , the extraction position is the high-pressure cylinder certain stage extraction position;

[0016] If 1.05pG>p i >0.95pG, the extraction position is the cold re-heater;

[0017] If 1.05pRH>p i >0.95pRH, the extraction position is the hot re-heater;

[0018] If pRH>p i >pI, the extraction position is the medium-pressure cylinder certain stage extraction position;

[0019] If 1.1pI>p i >0.9pI, the extraction position is the medium-pressure cylinder exhaust position.

[0020] As a preferred scheme of the method for adjusting the sliding pressure curve of the heating unit, the calculation of the steam work from the steam extraction point to the steam turbine exhaust includes defining the steam work from the steam extraction point to the steam turbine exhaust as N i ;

[0021] If p i >1.1p G , the extraction position is the high-pressure cylinder certain stage extraction position, and the formula is expressed as:

[0022] N i = 0.99G i [(h i -h G )+(h RH -h I )+(h I -h ex )]

[0023] If 1.05p G >p i >0.95p RH : the extraction position is cold reheat, the formula is expressed as

[0024] N i = 0.99G i [(h RH -h I )+(h I -h ex )]

[0025] If p RH >p i >p I : the extraction position is the extraction of some stage of the intermediate pressure cylinder, the formula is expressed as:

[0026] N i = 0.99G i [(h i -h I )+(h I -h ex )]

[0027] If 1.1p I >p i >0.9p I : the extraction position is the exhaust of the intermediate pressure cylinder, the formula is expressed as:

[0028] N i = 0.99G i (h I -h ex )

[0029] Wherein, h i represents the steam enthalpy of the extraction point i, h G represents the steam enthalpy of the cold reheat, h RH represents the steam enthalpy of the hot reheat; h I represents the steam enthalpy of the intermediate extraction; h ex represents the steam enthalpy of the turbine exhaust; G i is the extraction flow rate.

[0030] As a preferred scheme of the method for adjusting the sliding pressure curve of a heating unit, wherein: the calculation of the total theoretical work of all extraction steam points comprises calculation of a thermal power conversion coefficient formula represented as:

[0031] r = 1 + ∑N i / N

[0032] wherein ∑N i represents the total theoretical work of the extraction steam points; and the sliding pressure curve formula of the corrected design state is represented as:

[0033] p opt = arN + b

[0034] When p opt is greater than the rated value, the main steam pressure calculation method is applied to the stable load state, and when the load is raised or lowered, the main steam pressure is selected according to the original thermal logic; scanning is performed every ten minutes, and when the load change rate is less than 5% at the start and end time, the load is considered stable.

[0035] As a preferred scheme of the method for adjusting the sliding pressure curve of a heating unit, wherein: the fuzzy logic control comprises introducing an adaptive control mechanism to adjust r in real time, and the formula is represented as:

[0036] wherein α i represents an adaptive control coefficient, which is adjusted according to real-time monitoring data and historical data; N i (t) represents the theoretical work of the i-th extraction steam point at time t; and N(t) represents the electrical load at time t.

[0037] The input variables and membership functions are defined, including the steam supply G, the electrical load N, and the extraction steam pressure p i ; the output variables are defined, including the sliding pressure curve parameters a and b;

[0038] Fuzzy reasoning is performed, and according to the fuzzy values of the input variables G, N, and p i , reasoning is performed through a fuzzy rule base to obtain fuzzy output;

[0039] De-fuzzification processing is performed to convert the fuzzy output into specific numerical values a and b, and the centroid method is used for de-fuzzification, and the formula is represented as:

[0040] wherein μ j and μ k represent fuzzy membership degrees; a j and b k represent output values corresponding to the fuzzy membership degrees, respectively.

[0041] The corrected sliding pressure curve:

[0042] p opt = a(t) r(t) N(t) + b(t)

[0043] Wherein, a(t) and b(t) represent parameters dynamically adjusted based on fuzzy logic control algorithm; r(t) represents thermoelectric conversion coefficient dynamically adjusted through adaptive control algorithm; N(t) represents electric load at time t;

[0044] The constraint condition formula is expressed as:

[0045] p opt = min(a(t) r(t) N(t) + b(t), p rated )

[0046] When the calculated p opt is greater than the rated value, the main steam pressure takes the rated value p rated .

[0047] As a preferred scheme of the method for adjusting the sliding pressure curve of the heating unit, wherein: the judging of the load state and guiding of the unit operation includes that when N changes by 0-2% within the measurement start and end time, it is determined that the load change is small and the unit operation is stable; only the sliding pressure curve is fine-tuned, the amplitude of the adjustment coefficients a and b is small, and the stability of the main steam pressure is maintained;

[0048] When N changes by 2-5%, the load change is small and may affect the main steam pressure; the sliding pressure curve is moderately adjusted, the adjustment amplitude is increased, and it is ensured that the main steam pressure can follow the load change;

[0049] When N changes by more than 5%, the load change is large and may have a large impact on the unit operation, and a rapid response is needed to maintain the stable operation; the sliding pressure curve is rapidly and greatly adjusted to ensure that the main steam pressure rapidly adapts to the load change and shortens the measurement time; the sliding pressure point obtained by the mean value calculation within the measurement start and end time remains unchanged within the load section until the next stable load point is calculated.

[0050] A system for adjusting the sliding pressure curve of a heating unit by using any of the methods of the present application, comprising:

[0051] A data acquisition module collects steam extraction parameters and judges the steam extraction points, high-precision sensors are installed at each key position of the power plant, and the steam extraction parameters are monitored in real time;

[0052] A calculation and analysis module processes the collected steam extraction parameters, combines and calculates similar steam extraction points, and calculates the work of steam from the steam extraction point to the steam turbine exhaust;

[0053] A sliding pressure curve adjustment module calculates the thermoelectric conversion coefficient and corrects the sliding pressure curve according to the calculation result;

[0054] The control and optimization module introduces a fuzzy logic control system, optimizes and adjusts the sliding pressure curve according to real-time data, performs fuzzy logic control, optimizes the sliding pressure curve, judges the load state and guides the unit operation.

[0055] A computer device, comprising: a memory and a processor; the memory stores a computer program, comprising: the steps of the method of any one of the present application when the processor executes the computer program.

[0056] A computer readable storage medium having a computer program stored thereon, comprising: the steps of the method of any one of the present application when the computer program is executed by a processor.

[0057] The beneficial effects of the present application: the sliding pressure curve changes with the change of the unit steam supply, to guide the unit operation. The method is simple to implement, easy to edit and control, on the one hand, reduces the thermal consumption of power plant operation, makes the thermal economy of the whole plant always in the best state, on the other hand, easy to edit logic control, improves the automation level of power plant. BRIEF DESCRIPTION OF DRAWINGS

[0058] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor. Among them:

[0059] Fig. 1 is a whole flow chart of a method for adjusting the sliding pressure curve of a heating unit provided by the first embodiment of the present application. DETAILED DESCRIPTION

[0060] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should be within the scope of protection of the present application.

[0061] Embodiment 1, referring to Fig. 1, an embodiment of the present application provides a method for adjusting the sliding pressure curve of a heating unit, comprising:

[0062] S1: collecting extraction parameters and judging extraction points.

[0063] Further, the extraction parameters include steam supply G, extraction pressure p i , reading the current cold pressure pG , hot re-pressure p RH , medium-pressure cylinder exhaust pressure p I , electric power N.

[0064] Further, the steam extraction points include steam turbine steam extraction heating positions, including high-pressure cylinder extraction position, cold reheater, hot reheater, medium-pressure cylinder extraction position, and medium-pressure cylinder exhaust position; the steam extraction points are determined according to the steam extraction parameters, and there are multiple external steam supply points.

[0065] If p i >1.1p G , the extraction position is the high-pressure cylinder extraction position.

[0066] If 1.05pG>p i >0.95pG, the extraction position is the cold reheater.

[0067] If 1.05pRH>p i >0.95pRH, the extraction position is the hot reheater.

[0068] If pRH>p i >pI, the extraction position is the medium-pressure cylinder extraction position.

[0069] If 1.1pI>p i >0.9pI, the extraction position is the medium-pressure cylinder exhaust position.

[0070] It should be noted that the steam extraction parameters are collected, the steam extraction points are determined, similar steam extraction points are combined and calculated, the steam work from the steam extraction point to the steam turbine exhaust is calculated, the total theoretical work of all steam extractions is calculated, the electric-thermal conversion coefficient is calculated, the sliding pressure curve is corrected, the fuzzy logic control is performed, the sliding pressure curve is optimized, the load state is determined, and the unit operation is guided. Through the above series of steps, the sliding pressure curve can be adjusted in real time according to the steam supply amount, so as to realize the efficient operation of the combined heat and power unit under various working conditions.

[0071] S2: combining and calculating similar steam extraction points, and calculating the steam work from the steam extraction point to the steam turbine exhaust.

[0072] Further, the calculation of the steam work from the steam extraction point to the steam turbine exhaust includes defining the steam work from the steam extraction point to the steam turbine exhaust as N i .

[0073] Further, if p i >1.1p G , the extraction position is the high-pressure cylinder extraction position, and the formula is expressed as:

[0074] N i =0.99G i [(hi - h G ) + (h RH - h I ) + (h I - h ex )

[0075] Further, if 1.05p G > 0.95p i > 0.9p RH : the steam extraction position is cold reheat, the formula is expressed as:

[0076] N i = 0.99G i [(h RH - h I ) + (h I - h ex )]

[0077] Further, if p RH > 0.95p i > 0.9p I : the steam extraction position is the extraction of a certain stage of the intermediate pressure cylinder, the formula is expressed as:

[0078] N i = 0.99G i [(h i - h I ) + (h I - h ex )]

[0079] Further, if 1.1p I > 0.95p i > 0.9p I : the steam extraction position is the exhaust of the intermediate pressure cylinder, the formula is expressed as:

[0080] N i = 0.99G i (h I - h ex )

[0081] Wherein, h i represents the steam enthalpy of the extraction point i, h G represents the steam enthalpy of the cold reheat, h RH represents the steam enthalpy of the hot reheat; h I represents the steam enthalpy of the intermediate extraction; h ex represents the steam enthalpy of the turbine exhaust; G i is the steam extraction flow rate.

[0082] It should be noted that in actual operation, by merging the calculation of similar steam extraction points, the calculation complexity can be reduced, the calculation efficiency can be improved, and the overall operation state of the system can be more accurately reflected. In addition, by calculating the steam work of each extraction point, the sliding pressure curve can be more accurately adjusted to ensure the economy and stability of the system under different working conditions.

[0083] S3: Calculate the total theoretical work of all extraction points, calculate the electric-thermal conversion coefficient, and correct the sliding pressure curve.

[0084] Further, the calculation of the total theoretical work of all extraction points includes calculating the thermal-electric conversion coefficient formula:

[0085] r = 1 + ∑N i / N

[0086] where ∑N i represents the total theoretical work of the extraction points; and the corrected sliding pressure curve formula at the design state is:

[0087] p opt = arN + b

[0088] Further, when calculating p opt is greater than the rated value, the main steam pressure calculation method is applied to the stable load state, and when the load is rising or falling, the main steam pressure is selected according to the original thermal logic; scanning is performed every ten minutes, and when the load change rate is less than 5%, the load is considered to be stable.

[0089] It should be noted that the calculation method is applied to the stable load state, and the load change rate is scanned every 10 minutes. If the change rate is less than 5%, the load is considered to be stable, the average value within 10 minutes is read and the sliding pressure point is calculated, which remains unchanged within the load segment until the next stable load point is calculated.

[0090] S4: Perform fuzzy logic control to optimize the sliding pressure curve, judge the load state and guide the unit operation.

[0091] Further, the fuzzy logic control includes introducing an adaptive control mechanism to adjust r in real time, and the formula is:

[0092] where α i represents an adaptive control coefficient, which is adjusted according to real-time monitoring data and historical data; N i (t) represents the theoretical work of the i-th extraction point at time t; and N(t) represents the electric load at time t.

[0093] Further, define the input variables and membership functions, steam supply G, electric load N, extraction pressure p i; define output variable, slip pressure curve parameters a and b.

[0094] Further, fuzzy inference is performed, according to fuzzy values of input variables G, N, p i , etc., inference is performed through fuzzy rule base to obtain fuzzy output; input variable membership function.

[0095] Further, each input variable is converted into fuzzy set through membership function.

[0096] Further, for example, steam supply G can be divided into three fuzzy subsets of "low", "medium", and "high". Electric load N and extraction pressure p i can also be divided into multiple fuzzy subsets in a similar manner. According to experience and system requirements, fuzzy rule base is established, and examples are as follows: rule 1, if G is high and N is high, then a is high and b is high; rule 2, if G is low and N is low, then a is low and b is low; rule 3, if G is medium and N is medium, then a is medium and b is medium; rule 4, if G is high and N is low, then a is medium and b is low; rule 5, if G is low and N is high, then a is low and b is high.

[0097] Further, membership function examples: steam supply G membership function: μ G,low (G), μ G,medium (G), μ G,high (G); electric load N membership function: μ N,low (N), μ N,medium (N), μ N,high (N); extraction pressure p i membership function: μ pi,low (p i ), μ pi,medium (p i ), μ pi,high (p i ).

[0098] Further, output variable membership function: slip pressure curve parameters a and b can also be divided into multiple fuzzy subsets. Parameter a membership function μ a,low (a), μ a,medium (a), μ a,high (a). Parameter b membership function μ b,low (b), μ b,medium (b), μ b,high (b).

[0099] Further, defuzzification processing is performed to convert fuzzy output into specific numerical values a and b, and the defuzzification formula using the barycenter method is expressed as:

[0100] wherein, μ j and μ k represent fuzzy membership degree; a j and b k represent output values corresponding to fuzzy membership degree respectively. Further, the modified sliding pressure curve formula is represented as:

[0101] p opt = a(t) r(t) N(t) + b(t)

[0102] wherein, a(t) and b(t) represent parameters dynamically adjusted based on fuzzy logic control algorithm; r(t) represents thermoelectric conversion coefficient dynamically adjusted through adaptive control algorithm; N(t) represents electric load at time t.

[0103] Further, the constraint condition formula is represented as:

[0104] p opt = min(a(t) r(t) N(t) + b(t), p rated )

[0105] Further, when the calculated p opt is greater than the rated value, the main steam pressure takes the rated value p rated .

[0106] Further, the judgment of load state and guidance of unit operation includes that when N changes by 0-2% within the measurement start and end time, it is determined that the load change is small and the unit operation is stable; only the sliding pressure curve is fine-tuned, the adjustment coefficients a and b have small amplitude, and the stability of the main steam pressure is maintained.

[0107] Further, when N changes by 2-5%, the load change is small and may have an impact on the main steam pressure; the sliding pressure curve is moderately adjusted, the adjustment amplitude is increased, and it is ensured that the main steam pressure can follow the load change.

[0108] Further, when N changes by more than 5%, the load change is large and may have a large impact on the unit operation, which needs to be quickly responded to maintain stable operation; the sliding pressure curve is quickly and greatly adjusted to ensure that the main steam pressure quickly adapts to the load change and shortens the measurement time; within the measurement start and end time, the sliding pressure point obtained by the mean value calculation remains unchanged within the load section until the next stable load point is calculated.

[0109] It should be noted that through the introduction of feedback control mechanism and intelligent sliding pressure curve correction method based on fuzzy logic control, innovative optimization of the sliding pressure curve can be realized. This scheme can ensure that the system can reach the best sliding pressure point under different operating conditions and uncertainty conditions, and improve the overall operation efficiency and stability.

[0110] In another aspect, the embodiment also provides a system for adjusting the sliding pressure curve of a heat supply unit, comprising:

[0111] A data acquisition module collects steam extraction parameters and judges the steam extraction points, installs high-precision sensors at various key positions of the power plant to monitor the steam extraction parameters in real time;

[0112] A calculation analysis module processes the collected steam extraction parameters, combines and calculates similar steam extraction points, and calculates the work of steam from the steam extraction point to the turbine exhaust;

[0113] A sliding pressure curve adjustment module calculates the electric-thermal conversion coefficient and corrects the sliding pressure curve according to the calculation results;

[0114] A control and optimization module introduces a fuzzy logic control system, optimizes and adjusts the sliding pressure curve according to real-time data, performs fuzzy logic control, optimizes the sliding pressure curve, judges the load state and guides the unit operation.

[0115] If the above functions are realized in the form of software function units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application or the parts that essentially contribute to the prior art or parts of the technical solutions can be embodied in the form of a software product, which is stored in a storage medium and includes instructions for making a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and various program code storage media.

[0116] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a list of executable instructions for implementing logical functions, which can be embodied in any computer readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor or other system that can fetch and execute instructions from an instruction execution system, device or apparatus) or in conjunction with these instructions execution system, device or apparatus. For the purpose of this specification, "computer readable medium" can be any device that can contain, store, communicate, propagate or transport programs for use by an instruction execution system, device or apparatus or in conjunction with these instruction execution systems, devices or apparatus.

[0117] More specific examples (a non-exhaustive list) of the computer-readable medium include the following: an electrical connection (electronic) having one or more wires, a portable computer diskette (magnetic), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, and a portable compact disc read-only memory (CDROM). Additionally, the computer readable medium can even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, for instance via an optical scanner, then compiled, interpreted, or otherwise processed, using suitable tools, and then stored in a computer memory.

[0118] It should be understood that aspects of the application can be implemented in hardware, software, firmware or combinations thereof. In the embodiments described above, various steps or methods can be implemented, individually or in combination, by software or firmware stored in memory and executed on suitable instruction execution systems. For example, if implemented in hardware, as in another embodiment, any of the following technologies, known in the art, or their combinations, can be used: discrete logic circuitry having logic gates for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic gates, programmable gate arrays (PGA), field programmable gate arrays (FPGA), etc.

[0119] Embodiment 2, the following is an embodiment of the present application, provides a method for adjusting the sliding pressure curve of a heating unit. In order to verify the beneficial effects of the present application, economic benefit calculation and simulation experiment are carried out for scientific demonstration.

[0120] In order to verify the method for adjusting the sliding pressure curve of the heating unit provided by the present application, a specific embodiment is designed. The test is carried out in a certain thermal power plant, and the unit involved is a 600MW extraction heating unit. The purpose is to improve the operation efficiency and economy of the unit by dynamically adjusting the sliding pressure curve.

[0121] Test preparation:

[0122] Equipment preparation, the equipment used in the test includes high-precision pressure sensor, flow meter, enthalpy measuring instrument, etc., which are used for real-time monitoring and recording of extraction parameters.

[0123] The calculation and control system is configured with software of adaptive control algorithm and fuzzy logic control algorithm to ensure the real-time and accuracy of data processing and sliding pressure curve adjustment.

[0124] Parameter setting: extraction parameters include: steam supply, extraction pressure, cold re-pressing pressure, hot re-pressing pressure, medium pressure cylinder exhaust pressure and electric power.

[0125] The test will record different extraction point positions, including high-pressure cylinder extraction position, cold reheater, hot reheater, intermediate-pressure cylinder extraction position, and intermediate-pressure cylinder exhaust position.

[0126] Test implementation process:

[0127] Data collection: Under different load conditions, continuously collect extraction parameters. The collection frequency is once per second, and the test time lasts for 1 hour.

[0128] The data includes steam supply, extraction pressure, and corresponding cold reheater, hot reheater, intermediate-pressure cylinder exhaust pressure, and electric power of each extraction point.

[0129] According to the collected extraction parameters, the extraction point position is judged in real time. For example, when the extraction pressure is greater than 1.1 times the cold reheater pressure, it is judged as the high-pressure cylinder extraction point position.

[0130] Similar extraction points are combined and calculated, and the steam work of each extraction point is calculated using the formula:

[0131] Calculate the heat-electricity conversion coefficient, sum up the steam work of all extraction points, and calculate the total

[0132] According to the calculated heat-electricity conversion coefficient and electric load, dynamically adjust the sliding pressure curve. Scan the load change rate every 10 minutes, when the change rate is less than 5%, keep the sliding pressure point unchanged; when the change rate is greater than 5%, adjust to ensure the stability of the main steam pressure. The result part data is shown in Table 1.

[0133] Table 1 Example of extraction point parameter table

[0134] Extraction amount and work analysis:

[0135] From the table, it can be seen that the position and steam supply of different extraction points have different effects on steam work. The steam work of high-pressure cylinder extraction point and cold reheater extraction point is relatively large. The data of combined extraction points can better reflect the overall steam supply situation, simplify the calculation process, and improve the efficiency.

[0136] Calculation of heat-electricity conversion coefficient: According to the steam work of each extraction point, calculate the total work, and through the combined extraction point, calculate the total work, reduce repeated calculation, and improve the accuracy and efficiency.

[0137] Sliding pressure curve correction and optimization: Using fuzzy logic control method, according to the input variables such as steam supply, electric load and extraction pressure, dynamically adjust the sliding pressure curve parameters aaa and bbb.

[0138] Through real-time monitoring and fuzzy logic reasoning, ensure that the sliding pressure curve can quickly respond to load changes and maintain the best operating state.

[0139] The method of the present application optimizes the extraction point judgment and steam work calculation, combines the calculation of similar extraction points, and improves the calculation efficiency. The dynamic adjustment of the sliding pressure curve and the use of fuzzy logic control ensure that the unit can maintain the best operating performance under different load conditions, significantly improving the economy and stability. Through the calculation of the thermal-electric conversion coefficient and the correction of the sliding pressure curve, the present application can adapt to the changes of steam supply and electric load in real time, and is more intelligent and efficient than the traditional method.

[0140] It should be noted that the above examples are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and they should be covered in the scope of the claims of the present application.

Claims

1. A method for adjusting a sliding pressure curve of a heat supply unit, characterized in that, Comprise: Collecting steam extraction parameters to determine extraction points; Merging and calculating similar extraction points to calculate the work done by steam from extraction points to turbine exhaust; Finding the total theoretical work of all extractions, finding the electric-thermal conversion coefficient, and correcting the sliding pressure curve; Performing fuzzy logic control, optimizing the sliding pressure curve, determining the load state, and guiding the unit operation.

2. The method for adjusting the sliding pressure curve of a heat supply unit according to claim 1, characterized in that: The steam extraction parameters include steam supply amount G, steam extraction pressure p i , reading the current cold re-pressurization pressure p G , hot re-pressurization pressure p RH , medium-pressure cylinder exhaust pressure p I , electric power N.

3. The method for adjusting the sliding pressure curve of a heat supply unit according to claim 2, characterized in that: The extraction points include the positions of steam extraction for heat supply, including high-pressure cylinder extraction at a certain stage, cold reheater, hot reheater, extraction at a certain stage in the intermediate-pressure cylinder, and intermediate-pressure cylinder exhaust; According to the extraction parameters, the extraction points are determined, and there are multiple external steam supply points; If p i > 1.1p G , the steam extraction position is a certain stage steam extraction position of the high-pressure cylinder. If 1.05 pG > p i > 0.95 pG, the extraction position is the cold reheater. If 1.05 pRH > p i > 0.95 pRH, the extraction position is a hot reheater. If pRH> p i and pi, the extraction position is a certain extraction position of the intermediate-pressure cylinder. If 1.1 pI > p i > 0.9 pI, the extraction position is the position of the exhaust of the intermediate-pressure cylinder.

4. The method for adjusting the sliding pressure curve of a heat supply unit according to claim 3, characterized in that: The calculating the steam work from the extraction point to the turbine exhaust includes defining the steam work from the extraction point to the turbine exhaust as N i ; If p i >1.1p G When the steam extraction position is the steam extraction of a certain stage of the high-pressure cylinder, the formula is expressed as: N i = 0.99G i [(h i -h G )+(h RH -h I )+(h I -h ex )] if 1.05p G > p i > 0.95p RH : the extraction position is cold reheat, the formula is N i = 0.99G i [(h RH -h I )+(h I -h ex )] If p RH > p i > p I The steam extraction position is the steam extraction of a certain stage of the intermediate pressure cylinder, and the formula is expressed as: N i = 0.99G i [(h i -h I )+(h I -h ex )] If 1.1p I >p i >0.9p I The extraction position is the middle pressure cylinder exhaust, and the formula is expressed as: N i = 0.99G i (h I - h ex ) where h i represents the enthalpy of steam at extraction point i, h G represents the enthalpy of steam at cold reheat, h RH represents the enthalpy of steam at hot reheat; h I represents the enthalpy of steam at intermediate extraction; h ex represents the enthalpy of steam at turbine exhaust; G i is the extraction flow rate.

5. The method for adjusting the sliding pressure curve of a heat supply unit according to claim 4, characterized in that: The calculating all extraction steam theoretical work sum includes, the calculation of the thermal power conversion coefficient formula is expressed as: r = 1 + ∑N i / N where∑N i The theoretical work sum of supporting extraction points is represented, and the slip pressure curve formula of the correction design state is represented as p opt = arN + b When calculating p opt The rated value is greater than the main steam pressure, and the rated value calculation method is applied to the stable state of the load. When the load is raised or lowered, the main steam pressure is selected according to the original thermal logic. Scanning is performed every ten minutes, and when the load change rate at the start and end time is less than 5%, the load is considered stable.

6. The method for adjusting the sliding pressure curve of a heat supply unit according to claim 5, characterized in that: The performing fuzzy logic control includes introducing an adaptive control mechanism for adjusting r in real time, expressed in a formula as: wherein, a i represents an adaptive control coefficient, adjusted according to real-time monitoring data and historical data; N i (t) represents the theoretical work of the i-th steam extraction point at time t; N(t) represents the electric load at time t; Define input variables and membership functions, steam supply G, electric load N, extraction pressure p i ; define output variables, sliding pressure curve parameters a and b; The fuzzy inference is performed to obtain a fuzzy output according to the fuzzy values of the input variables G, N, p i and the like, through the fuzzy rule base. Deblurring is performed to convert the fuzzy output into specific numerical values a and b. The formula for deblurring using the barycenter method is expressed as: where μ j and μ k represent the fuzzy membership degree; a j and b k represent the output value corresponding to the fuzzy membership degree, respectively. The corrected sliding pressure curve is: p opt = a(t) r(t) N(t) + b(t) Where a(t) and b(t) represent parameters adjusted dynamically based on the fuzzy logic control algorithm; r(t) represents the thermal-electric conversion coefficient adjusted dynamically by the adaptive control algorithm; and N(t) represents the electric load at time t; The constraint condition formula is: p opt = min(a(t) r(t) N(t) + b(t), p rated ) When the calculated p opt is greater than the rated value, the main steam pressure is taken as the rated value p rated .

7. The method for adjusting the sliding pressure curve of a heat supply unit according to claim 6, characterized in that: The determination of the load state and the guidance of the unit operation include: when N changes by 0-2% within the measurement start and end time, it is determined that the load change is small, and the unit operation is stable; only the sliding pressure curve is fine-tuned, the adjustment coefficients a and b have a small amplitude, and the stability of the main steam pressure is maintained; When N changes by 2-5%, the load change is small, which may affect the main steam pressure; the sliding pressure curve is moderately adjusted, the adjustment amplitude is increased, and the main steam pressure is ensured to follow the load change; When N changes by more than 5%, the load change is large, which may have a large impact on the unit operation, and a rapid response is needed to maintain stable operation; the sliding pressure curve is rapidly and greatly adjusted to ensure that the main steam pressure quickly adapts to the load change and shortens the measurement time; within the measurement start and end time, the sliding pressure point calculated after the average remains unchanged within the load segment until the next stable load point is calculated.

8. A system for adjusting the sliding pressure curve of a heat supply unit using the method of any one of claims 1-7, characterized by: A data acquisition module that collects extraction parameters and determines extraction points, installs high-precision sensors at key positions in the power plant, and monitors extraction parameters in real time; A calculation and analysis module that processes the collected extraction parameters, merges and calculates similar extraction points, and calculates the work done by steam from extraction points to turbine exhaust; A sliding pressure curve adjustment module that finds the electric-thermal conversion coefficient and corrects the sliding pressure curve based on the calculation results; A control and optimization module that introduces a fuzzy logic control system, optimizes and adjusts the sliding pressure curve based on real-time data, performs fuzzy logic control, optimizes the sliding pressure curve, determines the load state, and guides the unit operation.

9. A computer device comprising: A memory and a processor; The memory stores a computer program, and the processor executes the computer program to implement the steps of the method for adjusting the sliding pressure curve of a heat supply unit.

10. A computer readable storage medium having stored thereon a computer program, characterized in that: The computer program is executed by the processor to implement the steps of the method for adjusting the sliding pressure curve of a heat supply unit.

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