Comprehensive improvement control system and method for frequency modulation performance of coal-fired unit

Abstract

The invention discloses a comprehensive improvement control system and method for the frequency modulation performance of a coal-fired unit. The system comprises a first delay module, a first pulse module, a first AND module, a first signal quality judgment module, a first inertia delay module, a first switching module, a first function module, a second function module, a first addition module, a second switching module and a second function module. The method comprises the following steps: when the output results of the first delay module and the first pulse module are 1, the output end of the first AND module is 1, otherwise, the output end of the first AND module is 0, and the final result of the first AND module acts on a primary frequency modulation action and then is delayed and triggered to obtain a final switching value output result signal. According to the method, the performance index calculated in real time is compared with the standard value or the expected set value in real time, a predictive control and rolling correction method is adopted, the qualification of the frequency modulation index is comprehensively ensured, and a foundation is laid for economical operation of a unit.

Description

Technical Field

[0001] This invention belongs to the field of intelligent control of generator sets, specifically relating to a comprehensive control system and method for improving the frequency regulation performance of coal-fired power units. Background Technology

[0002] Existing frequency modulation control technology has the following technical limitations: 1) Limitations of traditional control: Early control strategies that relied on fixed parameters (such as speed variability and dead zone settings) are difficult to adapt to complex operating conditions. In actual operation, problems such as response lag and large overshoot are prone to occur, especially during high load periods, when the turbine control valve opening is limited, resulting in insufficient regulation margin.

[0003] 2) Differences in dynamic characteristics between the boiler and the turbine: The boiler exhibits significant thermal inertia, and changes in fuel quantity take several minutes to be reflected in the output power. This results in the initial response of primary frequency regulation relying mainly on turbine-side adjustments. This dynamic mismatch between the boiler and turbine increases the difficulty of control.

[0004] 3) The complexity of multi-objective coordination: A single frequency regulation needs to simultaneously meet multiple dimensions of indicators such as response time, power contribution, and regulation accuracy. The traditional method of manually setting parameters can no longer meet the needs of refined control.

[0005] For the reasons mentioned above, there is an urgent need to develop a comprehensive control system and method for improving the frequency regulation performance of coal-fired power units, which takes into account the frequency regulation response speed, stability and economy, and achieves a comprehensive improvement in frequency regulation capability. Summary of the Invention

[0006] The purpose of this invention is to provide a comprehensive control system and method for improving the frequency regulation performance of coal-fired power units. Based on the assessment requirements for primary frequency regulation, this invention optimizes various aspects such as measurement signals, logic operations, execution systems (valve characteristic optimization), and control adjustments to improve the primary frequency regulation pass rate, reduce the amount of electricity required for assessment, and promote grid frequency stability while ensuring the safety of the unit.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: The comprehensive frequency regulation performance enhancement control system for coal-fired power units includes: a first delay module, a first pulse module, a first AND module, a first signal quality judgment module, a first inertial delay module, a first switching module, a first function module, a second function module, a first addition module, a second switching module, and a second function module; The output of the first pulse module is connected to the input of the first AND module; The output of the first signal quality judgment module is connected to the "S" terminal of the first switching module; the output of the first inertial delay module is connected to the "Pv2" terminal of the first switching module; the output of the first switching module is connected to the "Pv1" terminal of the first switching module; the output of the first switching module is connected to the input of the first function module; the outputs of the first function module and the second function module are both connected to the input of the first adder module; the output of the first adder module is connected to the "Pv1" terminal of the second switching module; and the output of the first AND module is connected to the "S" terminal of the second switching module. The output of the second switching module is connected to the input of the second function module.

[0008] A further improvement of the present invention is that a frequency modulation action is connected to the input terminal of the first delay module and the input terminal of the first pulse module respectively.

[0009] A further improvement of the present invention is that, after the parameters of the unit frequency modulation device are selected, they are respectively connected to the input terminal of the first signal quality judgment module and the input terminal of the first inertial delay module.

[0010] A further improvement of the present invention is that the primary frequency modulation speed difference is connected to the input terminal of the second function module.

[0011] A further improvement of the present invention is that the output terminal of the first delay module is connected to the input terminal of the first delay module.

[0012] A further improvement of the present invention is that the output terminal of the first AND module is connected to a delayed trigger after a frequency modulation action.

[0013] A further improvement of the present invention is that the output of the second switching module is connected to the primary frequency modulation correction value.

[0014] A further improvement of the present invention is that the output of the second function module is connected to the primary frequency modulation load correction value.

[0015] A comprehensive control method for improving the frequency regulation performance of coal-fired power units, the method being based on the aforementioned comprehensive control system for improving the frequency regulation performance of coal-fired power units, comprising: When the outputs of the first delay module and the first pulse module are both 1, the output of the first AND module is 1; otherwise, the output of the first AND module is 0. The final result of the first AND module is applied to the delayed trigger after a frequency modulation action to obtain the final switch output signal.

[0016] A further improvement of the present invention is that it further includes: If the output of the first signal quality judgment module is 1, it proves that the quality signal after the selection of the unit's frequency modulation device parameters is normal; otherwise, if the output is 0, it proves that the quality signal after the selection of the unit's frequency modulation device parameters is abnormal. The value output by the first inertial delay module is applied to the "Pv2" terminal of the first switching module, the output of the first signal quality judgment module is applied to the "S" terminal of the first switching module, and the output of the first switching module is applied to the "Pv1" terminal of the first switching module. The output of the first switching module is then calculated by the first function module to obtain the output value. The primary frequency modulation speed difference is calculated by the second function module to obtain the output value. The outputs of the first function module and the second function module are both applied to the value obtained by the first addition module after addition calculation, which is applied to the "Pv1" terminal of the second switching module. When the output of the first addition module is 1, the output of the second switching module is the output value of the first addition module; otherwise, when the output of the first addition module is 1, the output of the second switching module is 0. The final output value of the second switching module is the primary frequency regulation correction value, and the result of the second switching module after being processed by the second function module is the primary frequency regulation load correction value.

[0017] Compared with the prior art, the present invention has at least the following beneficial technical effects: The comprehensive frequency regulation performance improvement control system for coal-fired power units provided by this invention adopts big data analysis and artificial intelligence technology. By collecting real-time unit operating data (such as main steam pressure, valve opening, speed, etc.) and combining it with machine learning to establish a dynamic model, it can achieve parameter self-optimization and operating condition self-adaptation, effectively assisting in the deployment and application of frequency regulation control strategies.

[0018] The comprehensive frequency regulation performance improvement control method for coal-fired power units provided by the present invention adopts a preset control logic to accurately determine the effective frequency regulation, which significantly improves frequency regulation performance and reduces maintenance costs.

[0019] In summary, the comprehensive frequency regulation performance improvement control system and method for coal-fired power units described in this invention employs various mathematical algorithms for calculation and analysis to obtain an accurate speed-frequency model. This enables the design of a precise soft-sensor system for frequency deviation (slip) based on a closed-loop primary frequency regulation control strategy according to performance indicators. By comparing the real-time calculated performance indicators with standard or expected setpoints in real time, and using predictive control and rolling correction methods, the system comprehensively ensures the compliance of frequency regulation indicators, laying the foundation for the economical operation of the unit. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of a comprehensive control system for improving the frequency regulation performance of coal-fired power units.

[0022] Figure 2 This is a rendering of an embodiment of the present invention.

[0023] Explanation of reference numerals in the attached figures: 001. Primary frequency regulation action; 002. After selecting the parameters of the unit's frequency regulation device; 003. Primary frequency regulation speed difference; 004. First delay module; 005. First pulse module; 006. First AND module; 007. First signal quality judgment module; 008. First inertial delay module; 009. First switching module; 010. First function module; 011. Second function module; 012. First addition module; 013. Second switching module; 014. Second function module; 015. Delayed trigger after primary frequency regulation action; 016. Primary frequency regulation correction value; 017. Primary frequency regulation load correction value. Detailed Implementation

[0024] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0025] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0026] 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 indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0027] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0028] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0029] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0030] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this 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.

[0031] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0032] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0033] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0034] Example 1 like Figure 1 As shown, the comprehensive frequency regulation performance improvement control system for coal-fired power units provided by the present invention includes: a first delay module 004, a first pulse module 005, a first AND module 006, a first signal quality judgment module 007, a first inertial delay module 008, a first switching module 009, a first function module 010, a second function module 011, a first addition module 012, a second switching module 013, and a second function module 014; the output terminal of the first pulse module 005 is connected to the input terminal of the first AND module 006; the output terminal of the first signal quality judgment module 007 is connected to the "S" terminal of the first switching module 009, and the output of the first inertial delay module 008 is connected to the input terminal of the first AND module 006. The first switching module 006 is connected to the "Pv2" terminal of the first switching module 009, the output terminal of the first switching module 009 is connected to the "Pv1" terminal of the first switching module 009, and the output terminal of the first switching module 009 is connected to the input terminal of the first function module 010; the output terminals of the first function module 010 and the second function module 011 are both connected to the input terminal of the first addition module 012, the output terminal of the first addition module 012 is connected to the "Pv1" terminal of the second switching module 013, the output terminal of the first AND module 006 is connected to the "S" terminal of the second switching module 013, and the output terminal of the second switching module 013 is connected to the input terminal of the second function module 014.

[0035] In this embodiment, a frequency modulation action 001 is connected to the input terminal of the first delay module 004 and the input terminal of the first pulse module 005, respectively.

[0036] In this embodiment, after the parameters of the unit frequency modulation device are selected, 002 is connected to the input terminal of the first signal quality judgment module 007 and the input terminal of the first inertial delay module 008, respectively.

[0037] In this embodiment, the primary frequency modulation speed difference 003 is connected to the input terminal of the second function module 011.

[0038] In this embodiment, the output terminal of the first delay module 004 is connected to the input terminal of the first delay module 006.

[0039] In this embodiment, the output terminal of the first AND module 006 is connected to the delayed trigger 015 after a frequency modulation action.

[0040] In this embodiment, the output of the second switching module 013 is connected to the primary frequency modulation correction value 016.

[0041] In this embodiment, the output of the second function module 014 is connected to the primary frequency modulation load correction value 017.

[0042] Example 1 like Figure 1 The diagram shown is a schematic of a comprehensive frequency regulation performance enhancement control system for coal-fired power units. The comprehensive frequency regulation performance enhancement control system for coal-fired power units provided by this invention specifically includes: primary frequency regulation action 001, parameter selection of the unit's frequency regulation device 002, primary frequency regulation speed difference 003, first delay module 004, first pulse module 005, first AND module 006, first signal quality judgment module 007, first inertial delay module 008, first switching module 009, first function module 010, second function module 011, first addition module 012, second switching module 013, second function module 014, delayed triggering after primary frequency regulation action 015, primary frequency regulation correction value 016, and primary frequency regulation load correction value 017.

[0043] Figure 1 The control strategy logic diagram includes the following parts: The control connection method for delay trigger 015 after a frequency modulation action: the frequency modulation action 001 is connected to the input terminal of the first delay module 004 and the input terminal of the first pulse module 005 respectively. The output terminal of the first delay module 004 and the output terminal of the first pulse module 005 are both connected to the input terminal of the first AND module 006. The output terminal of the first AND module 006 is connected to the delay trigger 015 after a frequency modulation action.

[0044] The control connection method for the primary frequency adjustment correction value 016 is as follows: After the unit frequency modulation device parameters are selected, 002 is connected to the input terminals of the first signal quality judgment module 007 and the first inertial delay module 008, respectively. The output terminal of the first signal quality judgment module 007 is connected to the "S" terminal of the first switching module 009. The output terminal of the first inertial delay module 008 is connected to the "Pv2" terminal of the first switching module 009. The output terminal of the first switching module 009 is connected to the "Pv1" terminal of the first switching module 009. The output terminal is connected to the input terminal of the first function module 010; the primary frequency modulation speed difference 003 is connected to the input terminal of the second function module 011; the output terminals of the first function module 010 and the second function module 011 are both connected to the input terminal of the first adder module 012; the output terminal of the first adder module 012 is connected to the "Pv1" terminal of the second switching module 013; the output terminal of the first AND module 006 is connected to the "S" terminal of the second switching module 013; and the output terminal of the second switching module 013 is connected to the primary frequency modulation correction value 016.

[0045] Control connection method for primary frequency regulation load correction value 017: The output terminal of the second switching module 013 is connected to the input terminal of the second function module 014, and the output terminal of the second function module 014 is connected to the primary frequency regulation load correction value 017.

[0046] Example 3 like Figure 1 As shown, the comprehensive frequency regulation performance improvement control method for coal-fired power units provided by the present invention includes: In the first step, a frequency modulation action 001 is applied to the first delay module 004 and the first pulse module 005 respectively. When the output results of the first delay module 004 and the first pulse module 005 are both 1, the output terminal of the first AND module 006 is 1. Otherwise, the output terminal of the first AND module 006 is 0. The final result of the first AND module 006 is applied to the delayed trigger 015 after the frequency modulation action to obtain the final switch output result signal.

[0047] In the second step, after the unit frequency modulation device parameter selection 002 is performed, it is applied to the first signal quality judgment module 007 and the first inertial delay module 008 respectively. If the output of the first signal quality judgment module 007 is 1, it proves that the quality signal of the unit frequency modulation device parameter selection 002 is normal; otherwise, if the output is 0, it proves that the quality signal of the unit frequency modulation device parameter selection 002 is abnormal. The value calculated by the first inertial delay module 008 is applied to the "Pv2" terminal of the first switching module 009. The output of the first signal quality judgment module 007 is applied to the "S" terminal of the first switching module 009. The output of the first switching module 009 is applied to the first switching module. At the "Pv1" terminal of block 009, the output of the first switching module 009 is calculated by the first function module 010 to obtain the output value; the primary frequency modulation speed difference 003 is calculated by the second function module 011 to obtain the output value; the output of the first function module 010 and the output of the second function module 011 are both applied to the first addition module 012 to perform addition calculations to obtain the value, which is applied to the "Pv1" terminal of the second switching module 013. When the output of the first addition module 006 is 1, the output of the second switching module 013 is the output value of the first addition module 012; otherwise, when the output of the first addition module 006 is 1, the output of the second switching module 013 is 0.

[0048] Third, the final output value of the second switching module 013 is the primary frequency modulation correction value 016, and the result of the second switching module 013 after being processed by the second function module 014 is the primary frequency modulation load correction value 017.

[0049] The above method is to adjust the frequency regulation load and flow feedforward in real time based on the calculated output response qualification rate and contribution power qualification rate, so that the frequency regulation action results over a longer period of time are as close as possible to the ideal qualification range, and the unit meets the qualification index of frequency regulation response.

[0050] Example 4 like Figure 2 As shown, through the implementation and application of the technology of this invention in a certain coal-fired power generation unit, the control grid frequency signal of this invention is stable within the time range of 0s to 1600s, with the maximum deviation signal being 0.55Hz and the minimum being approximately -0.2Hz. This lays the foundation for the qualified frequency regulation indicators and economical operation of the unit, improves the primary frequency regulation qualification rate, reduces the amount of electricity required for assessment, and promotes the stability of the grid frequency.

[0051] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0052] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A comprehensive control system for improving the frequency regulation performance of coal-fired power units, characterized in that, include: First delay module (004), first pulse module (005), first AND module (006), first signal quality judgment module (007), first inertial delay module (008), first switching module (009), first function module (010), second function module (011), first addition module (012), second switching module (013), and second function module (014); The output terminal of the first pulse module (005) is connected to the input terminal of the first AND module (006); The output of the first signal quality judgment module (007) is connected to the "S" terminal of the first switching module (009), the output of the first inertial delay module (008) is connected to the "Pv2" terminal of the first switching module (009), the output of the first switching module (009) is connected to the "Pv1" terminal of the first switching module (009), and the output of the first switching module (009) is connected to the input of the first function module (010); the output of the first function module (010) and the output of the second function module (011) are both connected to the input of the first addition module (012), the output of the first addition module (012) is connected to the "Pv1" terminal of the second switching module (013), and the output of the first AND module (006) is connected to the "S" terminal of the second switching module (013). The output of the second switching module (013) is connected to the input of the second function module (014).

2. The comprehensive frequency regulation performance enhancement control system for coal-fired power units according to claim 1, characterized in that, A frequency modulation action (001) is connected to the input terminal of the first delay module (004) and the input terminal of the first pulse module (005), respectively.

3. The comprehensive frequency regulation performance enhancement control system for coal-fired power units according to claim 2, characterized in that, After the parameters of the unit frequency modulation device are selected (002), they are respectively connected to the input terminal of the first signal quality judgment module (007) and the input terminal of the first inertial delay module (008).

4. The comprehensive frequency regulation performance enhancement control system for coal-fired power units according to claim 3, characterized in that, The primary frequency modulation speed difference (003) is connected to the input of the second function module (011).

5. The comprehensive frequency regulation performance enhancement control system for coal-fired power units according to claim 4, characterized in that, The output of the first delay module (004) is connected to the input of the first AND module (006).

6. The comprehensive frequency regulation performance enhancement control system for coal-fired power units according to claim 5, characterized in that, The output of the first module (006) is connected to the delayed trigger (015) after a frequency modulation action.

7. The comprehensive frequency regulation performance enhancement control system for coal-fired power units according to claim 6, characterized in that, The output of the second switching module (013) is connected to the primary frequency modulation correction value (016).

8. The comprehensive frequency regulation performance enhancement control system for coal-fired power units according to claim 7, characterized in that, The output of the second function module (014) is connected to the primary frequency regulation load correction value (017).

9. A comprehensive control method for improving the frequency regulation performance of coal-fired power units, characterized in that, This method, based on the comprehensive frequency regulation performance improvement control system for coal-fired power units as described in claim 8, includes: When the outputs of the first delay module (004) and the first pulse module (005) are both 1, the output of the first AND module (006) is 1; otherwise, the output of the first AND module (006) is 0. The final result of the first AND module (006) is applied to the delayed trigger (015) after a frequency modulation action to obtain the final switch output signal.

10. The method for comprehensive improvement of frequency regulation performance control of coal-fired power units according to claim 9, characterized in that, Also includes: If the output of the first signal quality judgment module (007) is 1 after judgment, it proves that the quality signal of the unit frequency modulation device after parameter selection (002) is normal; otherwise, if the output is 0, it proves that the quality signal of the unit frequency modulation device after parameter selection (002) is abnormal. The value output by the first inertial delay module (008) is applied to the "Pv2" terminal of the first switching module (009), the output terminal of the first signal quality judgment module (007) is applied to the "S" terminal of the first switching module (009), the output terminal of the first switching module (009) is applied to the "Pv1" terminal of the first switching module (009), and the output terminal of the first switching module (009) is then calculated by the first function module (010) to obtain the output value. The primary frequency modulation speed difference (003) is calculated by the second function module (011) to obtain the output value. The output of the first function module (010) and the output of the second function module (011) are both applied to the value obtained by the first addition module (012) after addition calculation. The value is applied to the "Pv1" terminal of the second switching module (013). When the output of the first addition module (006) is 1, the output of the second switching module (013) is the output value of the first addition module (012). Conversely, when the output of the first addition module (006) is 1, the output of the second switching module (013) is 0. The final output value of the second switching module (013) is the primary frequency regulation correction value (016), and the result of the second switching module (013) after being processed by the second function module (014) is the primary frequency regulation load correction value (017).

Images