Reverse calculation method, system and equipment for low error of regulating stage temperature of steam turbine and medium

Abstract

The invention discloses a steam turbine regulating stage temperature low error reverse calculation method, system and device and a medium, and the method comprises the steps: determining the set stage efficiency according to the historical operation parameters of a steam turbine set or the stage efficiency under a rated load; adjusting stage temperature is set, and stage group efficiency is obtained through calculation according to the set adjusting stage temperature; calculating an error between the set stage group efficiency and the calculated stage group efficiency; and when the error is smaller than a preset value, the currently set regulating stage temperature serves as the final regulating stage temperature and is output, otherwise, the regulating stage temperature is reset, and the method, the system, the equipment and the medium can accurately calculate the regulating stage temperature.

Description

Technical Field

[0001] The invention belongs to the technical field of coal-fired power generation, and relates to a low-error reverse calculation method, system, equipment and medium for the temperature of a steam turbine regulating stage. Background Art

[0002] The existing steam turbine units with nozzle steam distribution have few temperature measurement points for the regulating stage, and the temperature of the regulating steam chamber changes greatly under variable operating conditions. The measurement points cannot reflect the actual temperature of the regulating stage. In addition, the temperature probe is located in a harsh environment, and the measurement point error increases with long-term operation, and even damage occurs. For steam turbines with high and medium pressure cylinders, the accuracy of the regulating stage temperature is very critical to the calculation of the leakage rate. For large steam turbine units, the main steam flow is generally calculated based on the Flügel formula, in which the accuracy of the regulating stage temperature is also crucial. However, the prior art does not provide a process for accurately calculating the regulating stage temperature. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a low-error inverse calculation method, system, equipment and medium for the temperature of a steam turbine regulating stage, which can accurately calculate the temperature of the regulating stage.

[0004] In order to achieve the above object, the present invention adopts the following technical scheme:

[0005] In one aspect, the present invention provides a method for low-error reverse calculation of steam turbine regulating stage temperature, comprising:

[0006] Determine the set stage efficiency according to the historical operating parameters of the steam turbine unit or the stage efficiency under rated load;

[0007] Set the regulating stage temperature, and calculate the stage group efficiency based on the set regulating stage temperature;

[0008] Calculate the error between the set stage group efficiency and the calculated stage group efficiency;

[0009] When the error is smaller than a preset value, the currently set regulating stage temperature is taken as the final regulating stage temperature and outputted; otherwise, the regulating stage temperature is reset.

[0010] The low-error reverse calculation method for the temperature of the steam turbine regulating stage of the present invention is further improved in that:

[0011] Furthermore, the process of determining the set stage efficiency according to the historical operating parameters of the steam turbine unit or the stage efficiency under rated load is as follows:

[0012] Calculating a set stage efficiency based on historical operating parameters of the steam turbine unit;

[0013] Alternatively, the stage group efficiency at rated load is used as the set stage group efficiency.

[0014] Furthermore, the regulating stage temperature is set, and the stage group efficiency η is calculated according to the set regulating stage temperature. j for:

[0015]

[0016] Among them, h c is the specific enthalpy at the stage group outlet, h s is the ideal specific enthalpy from the stage group to the outlet, h t is the specific enthalpy of the regulating stage, h t and h s Obtained by assuming the regulating stage temperature.

[0017] Furthermore, the preset value is 0.1‰.

[0018] In a second aspect of the present invention, the present invention provides a low-error reverse calculation system for the temperature of a steam turbine regulating stage, comprising:

[0019] The first setting module is used to determine the set stage group efficiency according to the historical operating parameters of the steam turbine unit or the stage group efficiency under the rated load;

[0020] The second setting module is used to set the regulating stage temperature and calculate the stage group efficiency according to the set regulating stage temperature;

[0021] A calculation module, used for calculating the error between the set stage group efficiency and the calculated stage group efficiency;

[0022] The judgment module is used to, when the error is less than a preset value, take the currently set regulating stage temperature as the final regulating stage temperature and output it; otherwise, reset the regulating stage temperature.

[0023] The low-error reverse calculation system for the temperature of the steam turbine regulating stage of the present invention is further improved in that:

[0024] Furthermore, the process of determining the set stage efficiency according to the historical operating parameters of the steam turbine unit or the stage efficiency under rated load is as follows:

[0025] Calculating a set stage efficiency based on historical operating parameters of the steam turbine unit;

[0026] Alternatively, the stage group efficiency at rated load is used as the set stage group efficiency.

[0027] Furthermore, the regulating stage temperature is set, and the stage group efficiency η is calculated according to the set regulating stage temperature. j for:

[0028]

[0029] Among them, h c is the specific enthalpy at the stage group outlet, h s is the ideal specific enthalpy from the stage group to the outlet, h t is the specific enthalpy of the regulating stage, h t and h s Obtained by assuming the regulating stage temperature.

[0030] Furthermore, the preset value is 0.1‰.

[0031] In a third aspect of the present invention, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method for inversely calculating the low error of the temperature of the steam turbine regulating stage when executing the computer program.

[0032] In a fourth aspect of the present invention, the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the inverse calculation method of the low error of the steam turbine regulating stage temperature are implemented.

[0033] The present invention has the following beneficial effects:

[0034] The low-error inverse calculation method, system, equipment and medium for the steam turbine regulating stage temperature described in the present invention calculate the regulating stage temperature from the regulating stage pressure and the stage group outlet temperature pressure according to the design parameters and actual operation data of the steam turbine unit in combination with the stage group efficiency during specific operation, thereby avoiding various factors that affect the regulating stage temperature during actual operation, thereby improving the accuracy of the regulating stage temperature, and is simple and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0036] Figure 1 This is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] In the description of the present invention, it should be understood that the terms “include” and “comprises” indicate the presence of described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0039] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0040] It should be further understood that the term "and / or" used in the present specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects are in an "or" relationship.

[0041] It should be understood that, although the terms first, second, third, etc. may be used to describe preset ranges, etc. in the embodiments of the present invention, these preset ranges should not be limited to these terms. These terms are only used to distinguish preset ranges from each other. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0042] The word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can usually be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0044] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0045] Embodiment 1

[0046] The principle of the low-error reverse calculation method for the temperature of the steam turbine regulating stage described in the present invention is:

[0047] The specific enthalpy after the adjustment stage is:

[0048] h t =f(P t ,T t )(1)

[0049] Among them, f is the calculation formula for the thermodynamic properties of water and water vapor, P t is the regulating stage pressure, T t For the adjustment stage temperature, we have:

[0050] T t =g(P t ,h t )(2)

[0051] According to the above formula, in order to obtain the regulating stage temperature, it is necessary to first obtain the regulating stage pressure and enthalpy value, among which the regulating stage pressure can be obtained through the actual operating measuring point.

[0052] The relationship between enthalpy and stage efficiency is:

[0053]

[0054] Among them, hc is the specific enthalpy at the stage group outlet, h s is the ideal specific enthalpy from the stage group to the outlet, so:

[0055]

[0056] Among them, η j and h s Unknown, and h t With h s There is a correlation, and the above equation needs to be solved to obtain the regulating stage temperature, which can be obtained by:

[0057] a) Set the stage group efficiency. Since the reduction in high-pressure cylinder efficiency mainly occurs in the regulating stage and the final stage, and the specific volume of each pressure stage of the high-pressure cylinder changes slightly, and the average diameter of each stage does not change much, the specific enthalpy drop of each stage changes slightly, and the efficiency of each stage changes slightly; when the operating conditions change, the pressure ratio before and after each pressure stage remains unchanged, the ideal enthalpy drop of the stage remains unchanged, and the various losses of the stage do not change much, so the stage efficiency does not change much either. Therefore, the average stage group efficiency can be calculated based on the historical operating parameters, and the average stage group efficiency can be used as the set stage group efficiency. In addition, under normal circumstances, the stage group efficiency can also be taken as the design value under the rated load, so the stage group efficiency under the rated load can also be used as the set stage group efficiency.

[0058] b) By setting a regulating stage temperature T t , combined with the actual measured regulating stage pressure P t , the specific enthalpy after the regulating stage is obtained by formula (1): t Then, the ideal specific enthalpy h from the stage group to the outlet is obtained by combining the stage group outlet parameters with the enthalpy entropy diagram. s , and then substitute it into formula (3) to calculate the stage group efficiency.

[0059] c) Perform error analysis on the stage group efficiency obtained in step b) and the set stage group efficiency obtained in step a). When the error is greater than 0.1‰, re-calculate the stage group efficiency by assuming the regulating stage temperature until the error meets the requirement. The assumed regulating stage temperature at this time is the final regulating stage temperature T t And output.

[0060] refer to Figure 1 Based on the above principle, the low error reverse calculation method of the steam turbine regulating stage temperature of the present invention comprises the following steps:

[0061] 1) Obtain the design parameters of the steam turbine unit and the DCS operation data, and obtain the high-pressure cylinder stage group efficiency design value, stage group outlet pressure temperature, and regulating stage pressure data;

[0062] 2) Calculate the set stage efficiency based on the historical operating parameters of the steam turbine unit, or use the stage efficiency under rated load as the set stage efficiency;

[0063] 3) Set the regulating stage temperature, and calculate the stage group efficiency according to the set regulating stage temperature;

[0064] 4) Calculate the error between the set stage group efficiency obtained in step 2) and the stage group efficiency obtained in step 3). When the error is less than a preset value, output the current regulating stage temperature; otherwise, go to step 3).

[0065] In this embodiment, the stage group efficiency η in step 3) is j Calculated by the following formula:

[0066]

[0067] Among them, h c is the specific enthalpy at the stage group outlet—operation data acquisition, h s is the ideal specific enthalpy from the stage group to the outlet, h t is the specific enthalpy of the regulating stage, h t and h s Obtained by assuming the regulating stage temperature.

[0068] In addition, it should be noted that, under normal circumstances, a section of extraction steam is taken from the stage group outlet; when the #1 high pressure heater is cut off, the high pressure cylinder exhaust steam is taken from the stage group outlet.

[0069] Embodiment 2

[0070] The low-error reverse calculation system for the temperature of the steam turbine regulating stage of the present invention comprises:

[0071] The first setting module is used to determine the set stage group efficiency according to the historical operating parameters of the steam turbine unit or the stage group efficiency under the rated load;

[0072] The second setting module is used to set the regulating stage temperature and calculate the stage group efficiency according to the set regulating stage temperature;

[0073] A calculation module, used for calculating the error between the set stage group efficiency and the calculated stage group efficiency;

[0074] The judgment module is used to, when the error is less than a preset value, take the currently set regulating stage temperature as the final regulating stage temperature and output it; otherwise, reset the regulating stage temperature.

[0075] As an implementation mode of the present invention, the process of determining the set stage efficiency according to the historical operating parameters of the steam turbine unit or the stage efficiency under rated load is as follows:

[0076] Calculating a set stage efficiency based on historical operating parameters of the steam turbine unit;

[0077] Alternatively, the stage group efficiency at rated load is used as the set stage group efficiency.

[0078] As an embodiment of the present invention, the regulating stage temperature is set, and the stage group efficiency η is calculated according to the set regulating stage temperature. j for:

[0079]

[0080] Among them, h c is the specific enthalpy at the stage group outlet, h s is the ideal specific enthalpy from the stage group to the outlet, h t is the specific enthalpy of the regulating stage, h t and h s Obtained by assuming the regulating stage temperature.

[0081] As an implementation manner of the present invention, the preset value is 0.1‰.

[0082] The division of modules in the embodiments of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, each functional module in each embodiment of the present application may be integrated into a processor, or may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated modules may be implemented in the form of hardware or in the form of software functional modules.

[0083] Embodiment 3

[0084] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the low error reverse calculation method of the steam turbine regulating stage temperature are implemented, for example, including: determining the set stage group efficiency according to the historical operating parameters of the steam turbine unit or the stage group efficiency under rated load; setting the regulating stage temperature, and calculating the stage group efficiency according to the set regulating stage temperature; calculating the error between the set stage group efficiency and the calculated stage group efficiency; when the error is less than the preset value, the currently set regulating stage temperature is used as the final regulating stage temperature and output, otherwise, the regulating stage temperature is reset. Wherein, the memory may include a memory, such as a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk memory, etc.; the processor, the network interface, and the memory are interconnected through an internal bus, and the internal bus may be an industrial standard architecture bus, a peripheral component interconnection standard bus, an extended industrial standard architecture bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. The memory is used to store programs. Specifically, the program may include program codes, and the program codes include computer operation instructions. The memory may include memory and nonvolatile memory and provides instructions and data to the processor.

[0085] Embodiment 4

[0086] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the low-error reverse calculation method of the steam turbine regulating stage temperature are implemented, for example, including: determining the set stage group efficiency according to the historical operating parameters of the steam turbine unit or the stage group efficiency under rated load; setting the regulating stage temperature, and calculating the stage group efficiency according to the set regulating stage temperature; calculating the error between the set stage group efficiency and the calculated stage group efficiency; when the error is less than a preset value, the currently set regulating stage temperature is used as the final regulating stage temperature and output, otherwise, the regulating stage temperature is reset. Specifically, the computer-readable storage medium includes, but is not limited to, for example, volatile memory and / or non-volatile memory. The volatile memory may include random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may include read-only memory (ROM), hard disk, flash memory, optical disk, magnetic disk, etc.

[0087] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0088] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0089] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0090] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0091] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and disclosure of the invention. This application is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

[0092] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

[0093] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A low-error inverse calculation method for steam turbine regulating stage temperature, characterized in that: include: Determine the set stage efficiency according to the historical operating parameters of the steam turbine unit or the stage efficiency under rated load; Set the regulating stage temperature, and calculate the stage group efficiency based on the set regulating stage temperature; Calculate the error between the set stage group efficiency and the calculated stage group efficiency; When the error is smaller than a preset value, the currently set regulating stage temperature is taken as the final regulating stage temperature and outputted; otherwise, the regulating stage temperature is reset.

2. The low error inverse calculation method for the temperature of the steam turbine regulating stage according to claim 1 is characterized in that: The process of determining the set stage group efficiency according to the historical operating parameters of the steam turbine unit or the stage group efficiency under rated load is as follows: Calculating a set stage efficiency based on historical operating parameters of the steam turbine unit; Alternatively, the stage group efficiency at rated load is used as the set stage group efficiency.

3. The low error inverse calculation method for the temperature of the steam turbine regulating stage according to claim 1, characterized in that: Set the regulating stage temperature and calculate the stage group efficiency η based on the set regulating stage temperature j for: Among them, h c is the specific enthalpy at the stage group outlet, h s is the ideal specific enthalpy from the stage group to the outlet, h t is the specific enthalpy of the regulating stage, h t and h s Obtained by assuming the regulating stage temperature.

4. The low error inverse calculation method for the temperature of the steam turbine regulating stage according to claim 1, characterized in that: The preset value is 0.1‰.

5. A low error reverse calculation system for temperature of steam turbine regulating stage, characterized in that: include: The first setting module is used to determine the set stage group efficiency according to the historical operating parameters of the steam turbine unit or the stage group efficiency under the rated load; The second setting module is used to set the regulating stage temperature and calculate the stage group efficiency according to the set regulating stage temperature; A calculation module, used for calculating the error between the set stage group efficiency and the calculated stage group efficiency; The judgment module is used to, when the error is less than a preset value, take the currently set regulating stage temperature as the final regulating stage temperature and output it; otherwise, reset the regulating stage temperature.

6. The low error reverse calculation system for steam turbine regulating stage temperature according to claim 5, characterized in that: The process of determining the set stage group efficiency according to the historical operating parameters of the steam turbine unit or the stage group efficiency under rated load is as follows: Calculating a set stage efficiency based on historical operating parameters of the steam turbine unit; Alternatively, the stage group efficiency at rated load is used as the set stage group efficiency.

7. The low error reverse calculation system for steam turbine regulating stage temperature according to claim 5, characterized in that: Set the regulating stage temperature and calculate the stage group efficiency η based on the set regulating stage temperature j for: Among them, h c is the specific enthalpy at the stage group outlet, h s is the ideal specific enthalpy from the stage group to the outlet, h t is the specific enthalpy of the regulating stage, h t and h s Obtained by assuming the regulating stage temperature.

8. The low error reverse calculation system for steam turbine regulating stage temperature according to claim 5, characterized in that: The preset value is 0.1‰.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method for inversely calculating the low error of the temperature of the steam turbine regulating stage as described in any one of claims 1 to 4 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method for inversely calculating the low error of the temperature of the steam turbine regulating stage as described in any one of claims 1 to 4 are implemented.

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