Method and system for adjusting sliding pressure curve of heat supply unit

Abstract

The invention relates to the technical field of computer wireless communication, and discloses a method and system for adjusting a sliding pressure curve of a heat supply unit, and the method comprises the steps: collecting steam extraction parameters, and judging a steam extraction point location; similar steam extraction points are calculated in a combined mode, and steam from the steam extraction points to steam turbine exhaust work is calculated; solving the sum of all theoretical steam extraction work, solving an electrothermal conversion coefficient, and correcting a sliding pressure curve; fuzzy logic control is carried out, a sliding pressure curve is optimized, the load state is judged, and the unit is guided to operate. The method has the beneficial effects 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 easy to implement, thermal control and edition are easy, on one hand, the operation heat consumption of the power plant is reduced, the heat economy of the whole plant is always in the optimal state, on the other hand, logic control is easy to edit, and the automation level of the power plant is improved.

Description

Technical Field

[0001] The invention relates to the technical field of steam turbine energy saving, and in particular to a method and a system for adjusting a sliding pressure curve of a heating unit. Background Art

[0002] Under the increasingly severe situation of energy constraints and economic development, tapping the energy-saving potential of coal-fired units and optimizing and controlling operating parameters are the inevitable choices for power plants to save energy and reduce consumption. Sliding pressure optimization is a common power plant steam turbine optimization method. 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 steam turbine. The sliding pressure curve is generally given by the steam turbine manufacturer or obtained through experimental measurement.

[0003] In recent years, with the popularization of cogeneration technology, a certain stage of steam extraction from the steam turbine is often used for industrial steam supply and heating. The steam supply will change with changes in user demand and heating demand, making the traditional fixed sliding pressure curve unable to effectively adapt to these changes. The cogeneration unit needs to frequently adjust the steam supply during operation to meet the needs under different operating conditions. In the context of deep cogeneration, a certain stage of steam extraction from the steam turbine is often used as industrial steam supply and heating steam, and the steam supply often changes with user demand and heating demand. The use of a certain sliding pressure curve cannot guarantee the correctness of the optimized sliding pressure point of the cogeneration unit. The optimized sliding pressure point should change with the change of steam supply.

[0004] The traditional sliding pressure curve is a fixed curve that cannot dynamically reflect the impact of changes in steam supply on unit operation, and the optimization effect is poor in actual operation. The fixed sliding pressure curve cannot be adjusted according to the real-time changes in steam supply and electrical load, and cannot achieve the best energy-saving effect. The steam supply of the cogeneration unit changes frequently, and the fixed sliding pressure curve cannot adapt to these changes, resulting in the main steam pressure and unit efficiency not being able to maintain the optimal state. Summary of the invention

[0005] In view of the above-mentioned problems, the present invention is proposed.

[0006] Therefore, the technical problem solved by the present invention is: how to modify the original sliding pressure curve by steam supply position and steam supply amount so that it can be adjusted in real time according to the change of steam extraction heating of the steam turbine.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for adjusting the sliding pressure curve of a heating unit, comprising:

[0008] Collect steam extraction parameters and determine the steam extraction point;

[0009] Combine similar extraction points and calculate the work done by steam from the extraction point to the turbine exhaust;

[0010] Calculate the sum of all theoretical work done by extraction steam, calculate the electric heat conversion coefficient, and correct the sliding pressure curve;

[0011] Carry out fuzzy logic control, optimize sliding pressure curve, judge load status and guide unit operation.

[0012] As a preferred solution of the method for adjusting the sliding pressure curve of the heating unit described in the present invention, the extraction steam parameters include the steam supply volume G, the extraction steam pressure p i , read the current cold repressure p G , thermal repressure p RH , Intermediate pressure cylinder exhaust pressure p I , electric power N.

[0013] As a preferred solution of the method for adjusting the sliding pressure curve of the heating unit described in the present invention, wherein: the extraction point includes, the position of the steam turbine extraction heating includes, the extraction position of a certain stage of the high-pressure cylinder, the cold reheater, the hot reheater, the extraction position of a certain stage in the intermediate-pressure cylinder, and the exhaust position of the intermediate-pressure cylinder; the extraction point is determined according to the extraction parameters, and there are multiple external steam supply points;

[0014] If p i >1.1p G , then the extraction position is the extraction position of a certain stage of the high-pressure cylinder;

[0015] If 1.05pG>p i >0.95pG, the extraction position is the cold reheater;

[0016] If 1.05pRH>p i >0.95pRH, the extraction position is the hot reheater;

[0017] If pRH>p i >pI, the extraction position is the extraction position of a certain stage of the intermediate pressure cylinder;

[0018] If 1.1pI>p i >0.9pI, the extraction position is the exhaust position of the medium pressure cylinder.

[0019] As a preferred solution of the method for adjusting the sliding pressure curve of the heating unit described in the present invention, wherein: the calculation of the work done by steam from the extraction point to the exhaust of the steam turbine includes defining the work done by steam from the extraction point to the exhaust of the steam turbine as N i ;

[0020] If p i >1.1p G When the extraction position is a certain stage of extraction of the high-pressure cylinder, the formula is expressed as:

[0021] N i =0.99G i [(hi -h G )+(h RH -h I )+(h I -h ex )]

[0022] If 1.05p G >p i >0.95p RH :When the extraction position is cold regeneration, the formula is expressed as

[0023] N i =0.99G i [(h RH -h I )+(h I -h ex )]

[0024] If p RH >p i >p I The extraction position is the extraction of a certain stage of the intermediate pressure cylinder, and the formula is expressed as:

[0025] N i =0.99G i [(h i -h I )+(h I -h ex )]

[0026] If 1.1p I >p i >0.9p I The extraction position is the exhaust of the intermediate pressure cylinder, and the formula is:

[0027] N i =0.99G i (h I -h ex )

[0028] Among them, h i represents the steam enthalpy at extraction point i, h G represents the steam enthalpy of cooling, h RH represents the steam enthalpy of heat regeneration; h I represents the steam enthalpy of the middle row; h ex represents the exhaust enthalpy of the steam turbine; G i represents the extraction steam flow rate.

[0029] As a preferred solution of the method for adjusting the sliding pressure curve of the heating unit described in the present invention, wherein: the sum of all theoretical work done by extraction steam includes calculating the thermal-electric conversion coefficient formula as follows:

[0030] r=1+∑Ni / N

[0031] Among them, ∑N i It represents the theoretical sum of the supported extraction points; the sliding pressure curve formula of the modified design state is expressed as:

[0032] p opt =arN+b

[0033] When calculating p opt If the main steam pressure is greater than the rated value, the rated value calculation method is applied to the state of stable load. When the load is increased or decreased, the main steam pressure is selected according to the original thermal logic. A scan is performed every ten minutes. When the load change rate between the start and end time is less than 5%, the load is considered stable.

[0034] As a preferred solution of the method for adjusting the sliding pressure curve of the heating unit described in the present invention, the fuzzy logic control includes introducing an adaptive control mechanism in order to adjust r in real time, and the formula is expressed as follows:

[0035]

[0036] Among them, α i Represents the adaptive control coefficient, which is adjusted according to real-time monitoring data and historical data; N i (t) represents the theoretical work done by the i-th extraction point at time t; N(t) represents the electrical load at time t;

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

[0038] Perform fuzzy reasoning based on the input variables G, N, p i The fuzzy values ​​of etc. are inferred through the fuzzy rule base to obtain the fuzzy output;

[0039] Defuzzification is performed to convert the fuzzy output into specific values ​​a and b. The centroid method is used to defuzzify the formula as follows:

[0040]

[0041] Among them, μ j and μ k represents fuzzy membership; a j and b k Respectively represent the output values ​​corresponding to the fuzzy membership;

[0042] Corrected sliding pressure curve:

[0043] p opt =a(t)r(t)N(t)+b(t)

[0044] Wherein, a(t) and b(t) represent the parameters dynamically adjusted based on the fuzzy logic control algorithm; r(t) represents the thermal-electric conversion coefficient dynamically adjusted by the adaptive control algorithm; N(t) represents the electrical load at time t;

[0045] The constraint formula is expressed as:

[0046] p opt =min(a(t)r(t)N(t)+b(t),p rated )

[0047] When calculating p opt When it is greater than the rated value, the main steam pressure takes the rated value p rated .

[0048] As a preferred solution of the method for adjusting the sliding pressure curve of the heating unit of the present invention, wherein: the said judging the load state and guiding the operation of the unit includes, when N changes by 0-2% during the measurement start and end time, judging that the load change is small and the unit is running smoothly; only fine-tuning the sliding pressure curve, adjusting the amplitudes of coefficients a and b to be small, maintaining the stability of the main steam pressure;

[0049] When N changes by 2-5%, the load changes slightly, which may affect the main steam pressure. The sliding pressure curve should be adjusted appropriately to increase the adjustment range to ensure that the main steam pressure can follow the load changes.

[0050] If N changes by more than 5%, the load changes greatly, which may have a great impact on the operation of the unit and requires a quick response to maintain stable operation; the sliding pressure curve is adjusted quickly and significantly to ensure that the main steam pressure quickly adapts to the load change and shorten the measurement time; within the measurement start and end time, the sliding pressure point calculated after averaging remains unchanged within the load section until the next stable load point is calculated.

[0051] A system for adjusting a sliding pressure curve of a heating unit using any method of the present invention, comprising:

[0052] The data acquisition module collects steam extraction parameters and determines the steam extraction points. High-precision sensors are installed at various key locations in the power plant to monitor the steam extraction parameters in real time.

[0053] The calculation and analysis module processes the collected extraction parameters, combines and calculates similar extraction points, and calculates the work done by steam from the extraction point to the turbine exhaust;

[0054] The sliding pressure curve adjustment module obtains the electric heat conversion coefficient and corrects the sliding pressure curve according to the calculation results;

[0055] 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, determines the load status and guides the operation of the unit.

[0056] A computer device comprises: a memory and a processor; the memory stores a computer program, comprising: the steps of implementing any one of the methods of the present invention when the processor executes the computer program.

[0057] A computer-readable storage medium stores a computer program, comprising: when the computer program is executed by a processor, the steps of implementing any one of the methods of the present invention are implemented.

[0058] The beneficial effects of the present invention are as follows: the sliding pressure curve changes with the steam supply of the unit to guide the operation of the unit. The method is simple to implement and easy to thermally control and edit. On the one hand, it reduces the heat consumption of the power plant operation, so that the thermal economy of the whole plant is always in the best state. On the other hand, it is easy to edit the logic control and improve the automation level of the power plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0060] Figure 1 An overall flow chart of a method for adjusting a sliding pressure curve of a heating unit provided in the first embodiment of the present invention. DETAILED DESCRIPTION

[0061] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0062] Example 1, reference Figure 1 , is an embodiment of the present invention, and provides a method for adjusting a sliding pressure curve of a heating unit, comprising:

[0063] S1: Collect steam extraction parameters and determine the steam extraction point.

[0064] Furthermore, the extraction steam parameters include steam supply volume G, extraction steam pressure p i , read the current cold repressure pG , thermal repressure p RH , Intermediate pressure cylinder exhaust pressure p I , electric power N.

[0065] Furthermore, the steam extraction points include the positions of steam turbine steam extraction for heating, including the steam extraction position of a certain stage of the high-pressure cylinder, the cold reheater, the hot reheater, the steam extraction position of a certain stage in the intermediate-pressure cylinder, and the exhaust position of the intermediate-pressure cylinder; the steam extraction points are judged based on the steam extraction parameters, and there are multiple external steam supply points.

[0066] If p i >1.1p G , then the extraction position is the extraction position of a certain stage of the high-pressure cylinder.

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

[0068] If 1.05pRH>p i >0.95pRH, the extraction location is the hot reheater.

[0069] If pRH>p i >pI, the extraction position is the extraction position of a certain stage of the intermediate pressure cylinder.

[0070] If 1.1pI>p i >0.9pI, the extraction position is the exhaust position of the medium pressure cylinder.

[0071] It should be noted that by collecting extraction parameters, determining extraction points, merging and calculating similar extraction points, calculating the work done by steam from the extraction point to the turbine exhaust, obtaining the sum of all theoretical work done by extraction, obtaining the electric-heat conversion coefficient, correcting the sliding pressure curve, and performing fuzzy logic control, optimizing the sliding pressure curve, determining the load state and guiding the unit operation. Through this series of steps, the sliding pressure curve can be adjusted in real time with the change of steam supply, thereby achieving efficient operation of the cogeneration unit under various working conditions.

[0072] S2: Combine and calculate similar extraction points, and calculate the work done by steam from the extraction point to the turbine exhaust.

[0073] Further, the calculation of 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 .

[0074] Furthermore, if p i >1.1p G When the extraction position is a certain stage of extraction of the high-pressure cylinder, the formula is expressed as:

[0075] N i =0.99G i [(hi -h G )+(h RH -h I )+(h I -h ex )]

[0076] Furthermore, if 1.05p G >p i >0.95p RH : When the extraction position is cold regeneration, the formula is expressed as:

[0077] N i =0.99G i [(h RH -h I )+(h I -h ex )]

[0078] Furthermore, if p RH >p i >p I The extraction position is the extraction of a certain stage of the intermediate pressure cylinder, and the formula is expressed as:

[0079] N i =0.99G i [(h i -h I )+(h I -h ex )]

[0080] Furthermore, if 1.1p I >p i >0.9p I The extraction position is the exhaust of the intermediate pressure cylinder, and the formula is:

[0081] N i =0.99G i (h I -h ex )

[0082] Among them, h i represents the steam enthalpy at extraction point i, h G represents the steam enthalpy of cooling, h RH represents the steam enthalpy of heat regeneration; h I represents the steam enthalpy of the middle row; h ex represents the exhaust enthalpy of the steam turbine; G i represents the extraction steam flow rate.

[0083] It should be noted that in actual operation, by merging and calculating similar extraction points, the calculation complexity can be reduced, the calculation efficiency can be improved, and the overall operation status of the system can be more accurately reflected. In addition, by calculating the steam work done by each extraction point, the sliding pressure curve can be adjusted more accurately to ensure the economy and stability of the system under different working conditions.

[0084] S3: Calculate the sum of theoretical work done by all extraction steam, calculate the electric heat conversion coefficient, and correct the sliding pressure curve.

[0085] Furthermore, the said obtaining the sum of all the theoretical work done by the extraction steam includes calculating the thermoelectric conversion coefficient as follows:

[0086] r=1+∑N i / N

[0087] Among them, ∑N i It represents the theoretical sum of the supported extraction points; the sliding pressure curve formula of the modified design state is expressed as:

[0088] p opt =arN+b

[0089] Furthermore, when calculating p opt If the main steam pressure is greater than the rated value, the rated value calculation method is applied to the state of stable load. When the load is increased or decreased, the main steam pressure is selected according to the original thermal logic. A scan is performed every ten minutes. When the load change rate between the start and end time is less than 5%, the load is considered stable.

[0090] It should be noted that the calculation method is applied to the state of stable load. The load change rate is scanned every 10 minutes. If the change rate is less than 5%, the load is considered stable. The average value within 10 minutes is read and the sliding pressure point is calculated. It remains unchanged within the load segment until the next stable load point is calculated.

[0091] S4: Perform fuzzy logic control, optimize the sliding pressure curve, determine the load status and guide the unit operation.

[0092] Furthermore, the fuzzy logic control includes introducing an adaptive control mechanism in order to adjust r in real time, and the formula is expressed as:

[0093]

[0094] Among them, α i Represents the adaptive control coefficient, which is adjusted according to real-time monitoring data and historical data; N i (t) represents the theoretical work done by the i-th extraction point at time t; N(t) represents the electrical load at time t.

[0095] Furthermore, the input variables and membership functions are defined, steam supply G, electrical load N, extraction steam pressure pi ; Define output variables, sliding pressure curve parameters a and b.

[0096] Furthermore, fuzzy reasoning is performed based on the input variables G, N, and p i The fuzzy values ​​of etc. are inferred through the fuzzy rule base to obtain the fuzzy output; the membership function of the input variables is obtained.

[0097] Furthermore, each input variable is converted into a fuzzy set through a membership function.

[0098] Furthermore, for example, the steam supply G can be divided into three fuzzy subsets: "low", "medium" and "high". i It can also be divided into multiple fuzzy subsets in a similar way. According to experience and system requirements, a fuzzy rule base is established, and the 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.

[0099] Furthermore, the membership function example: The membership function of steam supply G: μ G,low (G), μ G,medium (G), μ G,high (G); Membership function of electric load N: μ N,low (N), μ N,medium (N), μ N,high (N); extraction steam pressure p i Membership function of: μ pi,low (p i ), μ pi,medium (p i ), μ pi,high (p i ).

[0100] Furthermore, the output variable membership function: the sliding pressure curve parameters a and b can also be divided into multiple fuzzy subsets. The membership function μ of parameter a a,low (a), μ a,medium (a), μ a,high (a). Membership function μ of parameter b b,low (b), μ b,medium (b), μ b,high (b).

[0101] Furthermore, defuzzification is performed to convert the fuzzy output into specific values ​​a and b. The defuzzification formula using the centroid method is expressed as:

[0102]

[0103] Among them, μ j and μ k represents fuzzy membership; a j and b k Respectively represent the output values ​​corresponding to the fuzzy membership.

[0104] Furthermore, the corrected sliding pressure curve formula is expressed as:

[0105] p opt =a(t)r(t)N(t)+b(t)

[0106] Among them, a(t) and b(t) represent the parameters dynamically adjusted based on the fuzzy logic control algorithm; r(t) represents the thermal-electric conversion coefficient dynamically adjusted by the adaptive control algorithm; N(t) represents the electrical load at time t.

[0107] Furthermore, the constraint formula is expressed as:

[0108] p opt =min(a(t)r(t)N(t)+b(t),p rated )

[0109] Furthermore, when calculating p opt When it is greater than the rated value, the main steam pressure takes the rated value p rated .

[0110] Furthermore, the method of judging the load status and guiding the operation of the unit includes: when N changes by 0-2% during the measurement start and end time, judging that the load change is small and the unit operates smoothly; only fine-tuning the sliding pressure curve, adjusting the amplitudes of coefficients a and b to be small, and maintaining the stability of the main steam pressure.

[0111] Furthermore, when N changes by 2-5%, the load changes slightly, which may affect the main steam pressure. The sliding pressure curve is adjusted appropriately, and the adjustment range is increased to ensure that the main steam pressure can follow the load changes.

[0112] Furthermore, when N changes by more than 5%, the load changes significantly, which may have a significant impact on the operation of the unit and require a quick response to maintain stable operation; the sliding pressure curve is adjusted quickly and significantly to ensure that the main steam pressure quickly adapts to the load change and shorten the measurement time; within the measurement start and end time, the sliding pressure point calculated after averaging remains unchanged within the load section until the next stable load point is calculated.

[0113] It should be noted that by introducing feedback control mechanism and intelligent sliding pressure curve correction method based on fuzzy logic control, innovative optimization of sliding pressure curve can be achieved. This solution can ensure that the system can reach the optimal sliding pressure point under different operating conditions and uncertain conditions, and improve the overall operating efficiency and stability.

[0114] On the other hand, this embodiment also provides a system for adjusting the sliding pressure curve of a heating unit, which includes:

[0115] The data acquisition module collects steam extraction parameters and determines the steam extraction points. High-precision sensors are installed at various key locations in the power plant to monitor the steam extraction parameters in real time.

[0116] The calculation and analysis module processes the collected extraction parameters, combines and calculates similar extraction points, and calculates the work done by steam from the extraction point to the turbine exhaust;

[0117] The sliding pressure curve adjustment module obtains the electric heat conversion coefficient and corrects the sliding pressure curve according to the calculation results;

[0118] 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, determines the load status and guides the operation of the unit.

[0119] If the above functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0120] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and 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 instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0121] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0122] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0123] Example 2: The following is an embodiment of the present invention, which provides a method for adjusting the sliding pressure curve of a heating unit. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0124] In order to verify the method for adjusting the sliding pressure curve of the heating unit provided by the present invention, a specific embodiment is designed. The test is carried out in a thermal power plant, and the unit involved is a 600MW steam extraction heating unit. The purpose is to improve the operating efficiency and economy of the unit by dynamically adjusting the sliding pressure curve.

[0125] Test preparation:

[0126] Equipment preparation: The equipment used in the test includes high-precision pressure sensors, flow meters, enthalpy measuring instruments, etc., which are used to monitor and record steam extraction parameters in real time.

[0127] The computing and control system is equipped 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.

[0128] Parameter setting: Extraction parameters include: steam supply volume, extraction pressure, cold repressure, hot repressure, intermediate pressure cylinder exhaust pressure and electrical power.

[0129] The test will record the positions of different extraction points, namely, the extraction position of a certain stage of the high-pressure cylinder, the cold reheater, the hot reheater, the extraction position of a certain stage of the intermediate-pressure cylinder, and the exhaust position of the intermediate-pressure cylinder.

[0130] Experimental implementation process:

[0131] Data collection: Under different load conditions, the extraction parameters are continuously collected. The collection frequency is once per second, and the test lasts for 1 hour.

[0132] The data includes the steam supply volume, extraction pressure and the corresponding cold re-extraction, hot re-extraction and intermediate pressure cylinder exhaust pressure and electrical power for each extraction point.

[0133] The extraction point is determined in real time based on the collected extraction parameters. For example, when the extraction pressure is greater than 1.1 times the cold repressure, it is determined to be the extraction point of the high-pressure cylinder.

[0134] Similar extraction points are combined and the steam work done at each extraction point is calculated using the formula:

[0135] Calculate the heat-to-electricity conversion factor, summarize the steam work done at all extraction points, and calculate the total

[0136] According to the calculated thermal-electric conversion coefficient and electrical load, the sliding pressure curve is adjusted dynamically. The load change rate is scanned every 10 minutes. When the change rate is less than 5%, the sliding pressure point is kept unchanged; when the change rate is greater than 5%, adjustments are made to ensure the stability of the main steam pressure. The results are shown in Table 1.

[0137] Table 1 Example table of extraction point parameters

[0138]

[0139] Analysis of steam extraction and work done:

[0140] As can be seen from the table, the position and steam supply of different extraction points have different effects on steam work. The steam supply of the first extraction point of the high-pressure cylinder and the cold reheater extraction point is large, and the steam work is also correspondingly large. The data after merging the extraction points can better reflect the overall steam supply situation, simplify the calculation process, and improve efficiency.

[0141] Calculation of thermal-electric conversion coefficient: Calculate the total work based on the steam work of each extraction point. By combining the extraction points to calculate the total work, repeated calculations are reduced, improving accuracy and efficiency.

[0142] Correction and optimization of sliding pressure curve: Fuzzy logic control method is used to dynamically adjust the sliding pressure curve parameters aaa and bbb according to input variables such as steam supply, electrical load and extraction pressure.

[0143] Through real-time monitoring and fuzzy logic reasoning, it is ensured that the sliding pressure curve can quickly respond to load changes and maintain the best operating state.

[0144] The method of the present invention optimizes the extraction point judgment and steam work calculation, combines the calculation of similar extraction points, and improves the calculation efficiency. The sliding pressure curve is dynamically adjusted and fuzzy logic control is adopted to ensure that the unit can maintain the best operating performance under different load conditions, which significantly improves the economy and stability. Through the calculation of the thermal power conversion coefficient and the correction of the sliding pressure curve, the present invention can adapt to the changes in steam supply and electrical load in real time, which is more intelligent and efficient than traditional methods.

[0145] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention 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 invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for adjusting the sliding pressure curve of a heating unit, characterized in that: include: Collect steam extraction parameters and determine the steam extraction point; Combine similar extraction points and calculate the work done by steam from the extraction point to the turbine exhaust; Calculate the sum of all theoretical work done by extraction steam, calculate the electric heat conversion coefficient, and correct the sliding pressure curve; Carry out fuzzy logic control, optimize sliding pressure curve, judge load status and guide unit operation.

2. The method for adjusting the sliding pressure curve of a heating unit according to claim 1, characterized in that: The extraction steam parameters include steam supply volume G, extraction steam pressure p i , read the current cold repressure p G , thermal repressure P RH , Intermediate pressure cylinder exhaust pressure p I , electric power N.

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

4. The method for adjusting the sliding pressure curve of a heating unit according to claim 3, characterized in that: The calculation of 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 extraction position is a certain stage of extraction 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 : When the extraction position is cold regeneration, the formula is expressed as: N i =0.99G i [(h RH -h I )+(h I -h ex )] If p RH >p i >p I The extraction position is the 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 exhaust of the intermediate pressure cylinder, and the formula is: N i =0.99G i (h I -h ex ) Among them, h i represents the steam enthalpy at extraction point i, h G represents the steam enthalpy of cooling, h RH represents the steam enthalpy of heat regeneration; h I represents the steam enthalpy of the middle row; h ex represents the exhaust enthalpy of the steam turbine; G i represents the extraction steam flow rate.

5. The method for adjusting the sliding pressure curve of a heating unit according to claim 4, characterized in that: The method of obtaining the sum of all theoretical work done by extraction steam includes calculating the thermal-electric conversion coefficient as follows: r=1+∑N i / N Among them, ∑N i It represents the theoretical sum of the supported extraction points; the sliding pressure curve formula of the modified design state is expressed as: p opt =arN+b When calculating p opt If the main steam pressure is greater than the rated value, the rated value calculation method is applied to the state of stable load. When the load is increased or decreased, the main steam pressure is selected according to the original thermal logic. A scan is performed every ten minutes. When the load change rate between 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 heating unit according to claim 5, characterized in that: The fuzzy logic control includes introducing an adaptive control mechanism in order to adjust r in real time, and the formula is expressed as: Among them, α i Represents the adaptive control coefficient, which is adjusted according to real-time monitoring data and historical data; N i (t) represents the theoretical work done by the i-th extraction point at time t; N(t) represents the electrical load at time t; Define input variables and membership functions, steam supply G, electrical load N, extraction steam pressure p i ;Define output variables, sliding pressure curve parameters a and b; Perform fuzzy reasoning based on the input variables G, N, p i The fuzzy values ​​of etc. are inferred through the fuzzy rule base to obtain the fuzzy output; Defuzzification is performed to convert the fuzzy output into specific values ​​a and b. The defuzzification formula using the centroid method is expressed as: Among them, μ j and μ k represents fuzzy membership; a j and b k Respectively represent the output values ​​corresponding to the fuzzy membership; Corrected sliding pressure curve: p opt =a(t)r(t)N(t)+b(t) Wherein, a(t) and b(t) represent the parameters dynamically adjusted based on the fuzzy logic control algorithm; r(t) represents the thermal-electric conversion coefficient dynamically adjusted by the adaptive control algorithm; N(t) represents the electrical load at time t; The constraint formula is expressed as: p opt =min(a(t)r(t)N(t)+b(t),p rated ) When calculating p opt When it is greater than the rated value, the main steam pressure takes the rated value p rated .

7. The method for adjusting the sliding pressure curve of a heating unit according to claim 6, characterized in that: The method of judging the load state and guiding the operation of the unit includes: when N changes by 0-2% during the measurement start and end time, it is judged that the load change is small and the unit is running smoothly; only the sliding pressure curve is fine-tuned, and the amplitude of the adjustment coefficients a and b is small to maintain the stability of the main steam pressure; When N changes by 2-5%, the load changes slightly, which may affect the main steam pressure. The sliding pressure curve should be adjusted appropriately to increase the adjustment range to ensure that the main steam pressure can follow the load changes. If N changes by more than 5%, the load changes greatly, which may have a great impact on the operation of the unit and requires a quick response to maintain stable operation; the sliding pressure curve is adjusted quickly and significantly to ensure that the main steam pressure quickly adapts to the load change and shorten the measurement time; within the measurement start and end time, the sliding pressure point calculated after averaging remains unchanged within the load section until the next stable load point is calculated.

8. A system for adjusting the sliding pressure curve of a heating unit using the method according to any one of claims 1 to 7, characterized in that: The data acquisition module collects steam extraction parameters and determines the steam extraction points. High-precision sensors are installed at various key locations in the power plant to monitor the steam extraction parameters in real time. The calculation and analysis module processes the collected extraction parameters, combines and calculates similar extraction points, and calculates the work done by steam from the extraction point to the turbine exhaust; The sliding pressure curve adjustment module obtains the electric heat conversion coefficient and corrects the sliding pressure curve according to the calculation results; 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, determines the load status and guides the operation of the unit.

9. A computer device comprising: Memory and processor; The memory stores a computer program, characterized in that: when the processor executes the computer program, the steps of the method for adjusting the sliding pressure curve of the heating unit are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for adjusting the sliding pressure curve of a heating unit are implemented.

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