Automatic dry-wet state conversion control method and system for coal-fired units based on prediction model

Abstract

The application discloses a coal-fired unit dry-wet state automatic conversion control method and system based on a prediction model, and the system comprises a first greater than module, a first function module and a second function module, etc.; the method comprises the following steps: when the actual power of a generator meets the built-in constant of the first greater than module, and the intermediate point superheat prediction model output value meets the built-in constant of the first less than module, the wet state is triggered to be 1, otherwise the dry state is triggered; when the actual power of the generator meets the built-in constant of the second greater than module, and the intermediate point superheat prediction model output value meets the built-in constant of the third greater than module, and the water level selection value of a water storage tank meets the built-in constant of the second less than module, and the water level pneumatic regulating valve 1 control instruction, the water level pneumatic regulating valve 2 control instruction meet the fourth less than module or the water level regulating valve inlet electric valve off state is 1, the first SR module is triggered, the output of the first SR module is always 0, and at this time, the wet state is 0 and the dry state is 1.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of intelligent control of generator sets, and specifically relates to a dry-wet state automatic conversion control method and system for coal-fired generator sets based on a prediction model. BACKGROUND

[0002] During the operation of a coal-fired generator set, especially during the startup stage, variable load stage, and low load stage, the set will undergo a conversion process from wet state to dry state or from dry state to wet state. This process involves complex thermal and hydraulic changes, which puts high demands on the control system. Traditional control methods often struggle to accurately respond to these changes, leading to problems such as large parameter fluctuations and poor stability during the conversion process. Therefore, it is urgent to develop a dry-wet state automatic conversion control method and system for coal-fired generator sets based on a prediction model to address these phenomena and problems and achieve stable, safe, and efficient operation of the generator set. SUMMARY

[0003] The present application aims to provide a dry-wet state automatic conversion control method and system for coal-fired generator sets based on a prediction model. To improve the control accuracy and stability of dry-wet state conversion, a control method based on a prediction model is introduced. This method uses advanced data analysis techniques and artificial intelligence algorithms to monitor and predict key parameters in real time during the operation of the boiler, thereby adjusting the control strategy in advance to ensure smooth conversion.

[0004] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0005] The dry-wet state automatic conversion control system for coal-fired generator sets based on a prediction model comprises a first greater-than module, a first function module, a second function module, a first delay module, a first less-than module, a second greater-than module, a third greater-than module, a second less-than module, a first greater-selected-value module, a first NOT module, a first AND module, a third less-than module, a second delay module, a fourth less-than module, a second AND module, a third delay module, a first OR module, a second OR module, a third AND module, a fourth delay module, a first SR module, a first break delay module, and a second NOT module.

[0006] The output end of the first greater-than module is connected to the input end of the first delay module, the output end of the first function module is connected to the assignment end of the first delay module, the output end of the first delay module and the output end of the first less-than module are both connected to the input end of the first and module, the output end of the third less-than module is connected to the third delay module, the output end of the first and module and the output end of the third delay module are both connected to the second or module; the output end of the third greater-than module is connected to the input end of the second delay module, the output end of the second function module is connected to the assignment end of the second delay module, the output end of the first large-value module is connected to the fourth less-than module, the output end of the first non-module is connected to the second and module, the output end of the fourth less-than module and the output end of the second and module are both connected to the first or module, the output end of the first or module is connected to the fourth delay module, the output end of the second greater-than module, the output end of the second delay module, the output end of the second less-than module and the fourth delay module are all connected to the third and module; the output end of the second or module and the output end of the third and module are respectively connected to the "S" end and the "R" end of the first SR module, the output end of the first SR module is connected to the first break delay module, and the first break delay module is connected to the second non-module.

[0007] The further improvement of the present application is that the actual power of the generator is respectively connected to the second greater-than module and the third less-than module.

[0008] The further improvement of the present application is that the output value of the intermediate point overheating degree prediction model is respectively connected to the second function module, the first less-than module and the third greater-than module.

[0009] The further improvement of the present application is that the water level selection value of the water storage tank is respectively connected to the first greater-than module, the first function module and the second less-than module.

[0010] The further improvement of the present application is that the first water level of the water storage tank pneumatic regulating valve control instruction and the second water level of the water storage tank pneumatic regulating valve control instruction are both connected to the first large-value module.

[0011] The further improvement of the present application is that the open state of the water level regulating valve inlet electric valve of the water storage tank is connected to the first non-module.

[0012] The further improvement of the present application is that the closed state of the water level regulating valve inlet electric valve of the water storage tank is connected to the second and module.

[0013] The further improvement of the present application is that the output end of the first break delay module is connected to the wet state.

[0014] The further improvement of the present application is that the output end of the second non-module is connected to the dry state.

[0015] The coal-fired unit dry-wet state automatic conversion control method based on a prediction model comprises the following steps: when the actual power output of the generator meets the first greater-than module built-in constant, and the intermediate point superheat degree prediction model output value meets the first less-than module built-in constant, the wet state is triggered to be 1, otherwise the dry state is triggered; when the actual power output of the generator meets the second greater-than module built-in constant, and the intermediate point superheat degree prediction model output value meets the third greater-than module built-in constant, and the water tank water level selection value meets the second less-than module built-in constant, and the water tank water level pneumatic regulating valve 1 control instruction, the water tank water level pneumatic regulating valve 2 control instruction meets the fourth less-than module or the water tank water level regulating valve inlet electric valve off state is 1, the first SR module is triggered, the output of the first SR module is always 0, and at this time the wet state is 0 and the dry state is 1.

[0016] Compared with the prior art, the coal-fired unit dry-wet state automatic conversion control method based on a prediction model has at least the following beneficial technical effects:

[0017] The coal-fired unit dry-wet state automatic conversion control system based on a prediction model comprises multiple subsystems such as an intermediate point enthalpy control system, a water level control system and a circulating flow control system.

[0018] The coal-fired unit dry-wet state automatic conversion control method based on a prediction model monitors the changes of key parameters such as working medium flow, coal supply amount, water tank water level and intermediate point enthalpy in the dry-wet state conversion process, and can deeply analyze the mutual influence and change trend of the parameters through the prediction model, so as to realize accurate control of the control method.

[0019] In summary, the coal-fired unit dry-wet state automatic conversion control method and system based on a prediction model can significantly improve the stability and rapidity of the dry-wet state conversion process, and reduce the operation difficulty and risk. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0021] Figure 1 The principle diagram of the coal-fired unit dry-wet state automatic conversion control system based on a prediction model.

[0022] Figure 2 The effect picture of the embodiment of the present application.

[0023] Explanation of reference signs:

[0024] 001, generator actual power, 002, intermediate point superheat degree prediction model output value, 003, water tank water level selection value, 004, first water tank water level pneumatic regulating valve control instruction, 005, second water tank water level pneumatic regulating valve control instruction, 006, water tank water level regulating valve inlet electric valve open state, 007, water tank water level regulating valve inlet electric valve closed state, 008, first greater than module, 009, first function module, 010, second function module, 011, first delay module, 012, first less than module, 013, second greater than module, 014, third greater than module, 015, second less than module, 016, first greater selection value module, 017, first non-module, 018, first and module, 019, third less than module, 020, second delay module, 021, fourth less than module, 022, second and module, 023, third delay module, 024, first or module, 025, second or module, 026, third and module, 027, fourth delay module, 028, first SR module, 029, first break delay module, 030, second non-module, 031, wet state, 032, dry state. DETAILED DESCRIPTION

[0025] Hereinafter, only certain exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present application. Therefore, the drawings and the description are considered to be exemplary in nature rather than limiting.

[0026] In the description of the present application, it needs to be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0028] In the present invention, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0029] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0030] It will be understood that when used in this specification and the appended claims, the terms “comprises” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0031] It should also be understood that the terms used in the present specification are only for the purpose of describing particular embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0032] It should be further understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0033] The accompanying drawings illustrate various schematic diagrams of structures according to embodiments disclosed herein. These figures are not drawn to scale; for clarity, some details are exaggerated and some details may be omitted. The shapes of the various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are merely exemplary and may deviate in practice due to manufacturing tolerances or technical limitations. Those skilled in the art may design regions / layers with different shapes, sizes, and relative positions as needed.

[0034] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0035] Example 1

[0036] like Figure 1 As shown, the automatic dry-wet state conversion control system of a coal-fired unit based on a prediction model provided by the present invention specifically includes: actual power of the generator 001, output value of the intermediate point superheat prediction model 002, water level selection value of the water storage tank 003, control instruction of the first water storage tank water level pneumatic regulating valve 004, control instruction of the second water storage tank water level pneumatic regulating valve 005, open state of the inlet electric valve of the water storage tank water level regulating valve 006, closed state of the inlet electric valve of the water storage tank water level regulating valve 007, first greater than module 008, first function module 009, second function module 010, first delay module 011 , the first less than module 012, the second greater than module 013, the third greater than module 014, the second less than module 015, the first large selection module 016, the first not module 017, the first and module 018, the third less than module 019, the second delay module 020, the fourth less than module 021, the second and module 022, the third delay module 023, the first or module 024, the second or module 025, the third and module 026, the fourth delay module 027, the first SR module 028, the first off-delay module 029, the second not module 030, the wet state 031 and the dry state 032.

[0037] Figure 1 The control strategy logic diagram includes the following parts:

[0038] The wet state 031 comprises: the water tank water level selection value 003 is connected to the first greater than module 008, the output end of the first greater than module 008 is connected to the input end of the first delay module 011, the water tank water level selection value 003 is connected to the first function module 009, the output end of the first function module 009 is connected to the assignment end of the first delay module 011, the intermediate point overheating degree prediction model output value 002 is connected to the input end of the first less than module 012, the output end of the first delay module 011 and the output end of the first less than module 012 are all connected to the input end of the first and module 018, the generator actual generated power 001 is connected to the third less than module 019, the output end of the third less than module 019 is connected to the third delay module 023, the output end of the first and module 018 and the output end of the third delay module 023 are all connected to the second or module 025; the generator actual generated power 001 is connected to the second greater than module 013, the intermediate point overheating degree prediction model output value 002 is connected to the third greater than module 014, the output end of the third greater than module 014 is connected to the input end of the second delay module 020, the intermediate point overheating degree prediction model output value 002 is connected to the second function module 010, the output end of the second function module 010 is connected to the assignment end of the second delay module 020, the water tank water level selection value 003 is connected to the second less than module 015, the first water tank water level pneumatic regulating valve control instruction 004 and the second water tank water level pneumatic regulating valve control instruction 005 are all connected to the first greater than value module 016, the output end of the first greater than value module 016 is connected to the fourth less than module 021, the water tank water level regulating valve inlet electric valve open state 006 is connected to the first non-module 017, the output end of the first non-module 017 and the water tank water level regulating valve inlet electric valve close state 007 are all connected to the second and module 022, the output end of the fourth less than module 021 and the output end of the second and module 022 are all connected to the first or module 024, the output end of the first or module 024 is connected to the fourth delay module 027, the output end of the second greater than module 013, the output end of the second delay module 020, the output end of the second less than module 015, the fourth delay module 027 are all connected to the third and module 026; the output end of the second or module 025 and the output end of the third and module 026 are respectively connected to the “S” end and “R” end of the first SR module 028, the output end of the first SR module 028 is connected to the first break delay module 029, the output end of the first break delay module 029 is connected to the wet state 031.

[0039] The dry state 032 comprises: the first break delay module 029 is connected to the second non-module 030, and the output end of the second non-module 030 is connected to the dry state 032.

[0040] Embodiment 2

[0041] The coal-fired unit dry-wet state automatic conversion control method based on a prediction model provided by the application comprises:

[0042] (1) Model establishment: Establish an intermediate point superheat prediction model through mechanism modeling and data identification. Excessive or insufficient intermediate point superheat will affect the stable operation of the system. Through the prediction model, timely adjustments can be made to avoid overheating or overcooling phenomena; the prediction model can help operation and maintenance personnel to discover potential problems in advance, reduce the risk of sudden failures, and provide scientific decision-making basis for management to help develop more reasonable production plans and operation strategies; through long-term monitoring and analysis of the intermediate point superheat, the risk of system operation can be evaluated to provide a reference for risk management and preventive measures.

[0043] (2) Parameter identification: One of the criteria based on the intermediate point superheat prediction model is adopted, and the load, main steam pressure, and intermediate point temperature are identified to optimize the controller parameters. Through the control logic, automatic judgment of unit dry / wet state conversion, adaptive adjustment of feedwater flow regulation, and adaptive control of control parameters are realized; for units with intermediate point temperature control, a fusion control strategy is adopted to realize automatic conversion of dry / wet state; real-time data is used for trend analysis to predict the best opportunity for dry / wet state conversion, thereby reducing human intervention and improving the accuracy and efficiency of conversion.

[0044] (3) Non-disturbance switching control strategy: A non-disturbance switching control strategy for the coordinated control system of coal-fired units during dry / wet state conversion is proposed, and the control logic is improved to realize automatic control throughout the dry / wet state conversion process.

[0045] The embodiment specifically includes: when the generator real power 001 meets the built-in constant of the first greater than module 008, and the intermediate point superheat prediction model output value 002 meets the built-in constant of the first less than module 012, the wet state 031 is triggered to be 1, otherwise the dry state 032 is triggered; when the generator real power 001 meets the built-in constant of the second greater than module 013, and the intermediate point superheat prediction model output value 002 meets the built-in constant of the third greater than module 014, and the water tank water level selection value 003 meets the built-in constant of the second less than module 015, and the water tank water level pneumatic regulating valve 1 control instruction 004 and the water tank water level pneumatic regulating valve 2 control instruction 005 meet the fourth less than module 021 or the water tank water level regulating valve inlet electric valve off state 007 is 1, the first SR module 028 is triggered, the output of the first SR module 028 is always 0, and at this time the wet state 031 is 0 and the dry state 032 is 1.

[0046] Embodiment 3

[0047] As Figure 2As shown, through the implementation and application of the technology of the present application, the effectiveness of the automatic control system is verified through simulation debugging and field implementation, ensuring smooth transition of the dry-wet state conversion process. In general, the dry-wet state automatic conversion control technology for coal-fired units based on prediction models utilizes advanced control algorithms and prediction models to achieve efficient and stable conversion between dry and wet states for coal-fired units. This technology not only improves the operating efficiency and economy of thermal power units, but also enhances their response capability to grid peak shaving requirements, and has important practical application value and broad development prospects.

[0048] The basic principles and main features of the present application and the advantages of the present application are shown and described above, and it is obvious to those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and it is intended to encompass all variations falling within the meaning and scope of the equivalent elements of the claims. Any reference signs in the claims should not be considered as limiting the claims involved.

[0049] In addition, it should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description manner of the specification is only for clarity, those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that those skilled in the art can understand. The above is only to illustrate the technical idea of the present application, and cannot limit the protection scope of the present application, and any modification made on the basis of the technical solutions according to the technical idea of the present application falls within the protection scope of the claims of the present application.

Claims

1. A dry-wet state automatic conversion control system for coal-fired units based on a prediction model, characterized by: It includes a first greater than module (008), a first function module (009), a second function module (010), a first delay module (011), a first less than module (012), a second greater than module (013), a third greater than module (014), a second less than module (015), a first selection module (016), a first negation module (017), a first and module (018), a third less than module (019), a second delay module (020), a fourth less than module (021), a second and module (022), a third delay module (023), a first or module (024), a second or module (025), a third and module (026), a fourth delay module (027), a first SR module (028), a first break delay module (029) and a second negation module (030); The output end of the first greater than module (008) is connected to the input end of the first delay module (011), the output end of the first function module (009) is connected to the assignment end of the first delay module (011), the output end of the first delay module (011) and the output end of the first less than module (012) are both connected to the input end of the first AND module (018), the output end of the third less than module (019) is connected to the third delay module (023), the output end of the first AND module (018) and the output end of the third delay module (023) are both connected to the second OR module (025); the output end of the third greater than module (014) is connected to the input end of the second delay module (020), the output end of the second function module (010) is connected to the assignment end of the second delay module (020), and the output end of the first large selection module (016) is connected to the fourth less than module (021). The output end of the first negative module (017) is connected to the second AND module (022), the output end of the fourth less than module (021) and the output end of the second AND module (022) are both connected to the first OR module (024), the output end of the first OR module (024) is connected to the fourth delay module (027), the output end of the second greater than module (013), the output end of the second delay module (020), the output end of the second less than module (015) and the fourth delay module (027) are all connected to the third AND module (026); the output end of the second OR module (025) and the output end of the third AND module (026) are respectively connected to the "S" end and the "R" end of the first SR module (028), the output end of the first SR module (028) is connected to the first break delay module (029), and the first break delay module (029) is connected to the second negative module (030).

2. The dry-wet state automatic conversion control system for a coal-fired unit based on a prediction model according to claim 1 is characterized in that: The actual power generated by the generator (001) is connected to the second greater than module (013) and the third less than module (019) respectively.

3. The dry-wet state automatic conversion control system for a coal-fired unit based on a prediction model according to claim 2 is characterized in that: The intermediate point superheat prediction model output value (002) is connected to the second function module (010), the first less than module (012) and the third greater than module (014) respectively.

4. The dry-wet state automatic conversion control system for a coal-fired unit based on a prediction model according to claim 3 is characterized in that: The water level selection value (003) of the water storage tank is respectively connected to the first greater than module (008), the first function module (009) and the second less than module (015).

5. The dry-wet state automatic conversion control system for a coal-fired unit based on a prediction model according to claim 4 is characterized in that: The first water storage tank water level pneumatic regulating valve control instruction (004) and the second water storage tank water level pneumatic regulating valve control instruction (005) are both connected to the first large value selection module (016).

6. The dry-wet state automatic conversion control system for a coal-fired unit based on a prediction model according to claim 5 is characterized in that: The water level regulating valve inlet electric valve open state (006) of the water storage tank is connected to the first non-module (017).

7. The dry-wet state automatic conversion control system for a coal-fired unit based on a prediction model according to claim 6 is characterized in that: The closed state (007) of the electric valve inlet of the water level regulating valve of the water storage tank is connected to the second AND module (022).

8. The dry-wet state automatic conversion control system for a coal-fired unit based on a prediction model according to claim 7 is characterized in that: The output end of the first off-delay module (029) is connected to the wet state (031).

9. The dry-wet state automatic conversion control system for a coal-fired unit based on a prediction model according to claim 8, characterized in that: The output terminal of the second non-module (030) is connected to the dry state (032).

10. A method for automatically controlling dry-wet state conversion of a coal-fired unit based on a prediction model, characterized in that: The method is based on the dry-wet state automatic conversion control system of the coal-fired unit based on the prediction model according to claim 9, comprising: when the actual power (001) of the generator satisfies the first built-in constant greater than the module (008), and the output value (002) of the intermediate point superheat prediction model satisfies the first built-in constant less than the module (012), the wet state (031) is triggered to be 1, otherwise the dry state (032) is triggered; when the actual power (001) of the generator is second greater than the built-in constant of the module (013 ... When the third is greater than the built-in constant of the module (014), and the water level selection value (003) of the water storage tank satisfies the built-in constant of the second less than module (015), and the water level pneumatic regulating valve 1 control instruction (004) and the water level pneumatic regulating valve 2 control instruction (005) of the water storage tank satisfy the fourth less than module (021), or the closed state (007) of the inlet electric valve of the water level regulating valve of the water storage tank is 1, the first SR module (028) is triggered, and the output of the first SR module (028) is always 0. At this time, the wet state (031) is 0 and the dry state (032) is 1.

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