Method and system for estimating thermoelectric efficiency curve of coal-fired generator set

Abstract

The invention discloses a method and a system for estimating a thermoelectric efficiency curve of a coal-fired power generation unit, and belongs to the technical field of coal-fired power generation. The method comprises the steps that the main steam temperature, the main steam pressure, the main steam flow and the unit actual power of the coal-fired power generating unit are obtained, and the main steam inlet ratio enthalpy is calculated according to the main steam temperature and the main steam pressure; the steam inlet heat of the steam turbine is determined according to the main steam inlet ratio enthalpy and the main steam flow; forming a two-dimensional sample point set based on the steam inlet heat and the actual power of the unit, calculating the density value of each sample point in the two-dimensional sample point set, and determining maximum density peak value sample points under different powers to construct a feature sample point set; and performing multiple regression modeling on the feature sample point set to generate a thermoelectric conversion efficiency curve of the unit. The thermoelectric conversion efficiency of the unit in different load sections can be reflected through the thermoelectric conversion efficiency curve, and the problem that the thermoelectric conversion efficiency of the unit is regarded as a constant value to affect the operation efficiency of the unit is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of coal-fired power generation, and in particular to a method and system for estimating a thermoelectric efficiency curve of a coal-fired power generation unit. Background Art

[0002] The statements in this section merely mention background art related to the present invention and do not necessarily constitute prior art.

[0003] The working principle of coal-fired power generation units is mainly to convert the heat energy generated by coal powder combustion into the heat energy of high-temperature and high-pressure steam through the boiler, and then convert the heat energy of high-temperature and high-pressure steam into the rotational mechanical energy of the turbine through the steam turbine, and finally the generator coaxially connected to the steam turbine converts the rotational mechanical energy of the blades into electrical energy. However, the thermoelectric conversion efficiency of each unit is different, and the thermoelectric conversion efficiency of the same unit in different load sections is also different. Increasing the power generation and operating time of coal-fired power generation units at high efficiency points and reducing the power generation and operating time at low efficiency points are crucial to reducing the unit carbon emissions of coal-fired power generation units and improving the production efficiency of coal-fired power generation units.

[0004] The thermal-electric conversion efficiency of coal-fired power generation units is an important unit performance indicator and an important reference for adjusting the unit's operating mode. It is generally believed that the thermal-electric conversion efficiency of the unit is a fixed design value. However, in the actual operation of the unit, different load sections often have different thermal-electric conversion efficiencies. If the unit operates at a low conversion efficiency point for a long time, it will lead to an increase in the unit's unit carbon emissions and a decrease in the unit's revenue. Summary of the invention

[0005] In order to address the deficiencies in the prior art, the present invention provides a method, system, electronic device, computer-readable storage medium and computer program product for estimating the thermoelectric efficiency curve of a coal-fired power generation unit. The method, system, electronic device, computer-readable storage medium and computer program product are based on the unit operation data, estimate the steam inlet heat of the turbine, and perform density peak calculation on the estimated heat result and the power generation of the unit. Combined with multivariate regression analysis, the estimated result of the thermoelectric conversion efficiency curve is obtained, which can effectively give the thermoelectric conversion efficiency of the unit in different load sections, and provide supporting information for optimizing the unit operation mode and improving the unit operation efficiency.

[0006] In a first aspect, the present invention provides a method for estimating a thermal efficiency curve of a coal-fired power generation unit; A method for estimating a thermal efficiency curve of a coal-fired power generation unit, comprising: Obtain the main steam temperature, main steam pressure, main steam flow rate and actual power of the coal-fired power generation unit, calculate the main steam intake ratio according to the main steam temperature and the main steam pressure; determine the steam intake heat of the steam turbine according to the main steam intake ratio and the main steam flow rate; A two-dimensional sample point set is formed based on the inlet steam heat and the actual power of the unit, the density value of each sample point in the two-dimensional sample point set is calculated, and the maximum density peak sample point under different powers is determined to construct a characteristic sample point set; Multivariate regression modeling is performed on the characteristic sample point set to generate the thermoelectric conversion efficiency curve of the unit.

[0007] In some implementations, calculating the main steam intake ratio according to the main steam temperature and the main steam pressure includes: According to the ratio of the main steam pressure to the pressure constant, respectively calculating the ideal gas part and the residual gas part of the dimensionless Gibbs free energy; The main steam inlet ratio is calculated based on the ideal gas part and the residual gas part of the dimensionless Gibbs free energy in combination with the main steam temperature.

[0008] In some embodiments, determining the steam inlet heat of the turbine based on the main steam inlet ratio and the main steam flow rate is specifically: converting the main steam flow rate into units and multiplying it by the main steam inlet ratio to obtain the steam inlet heat of the turbine.

[0009] In some embodiments, the density value is expressed as: , In the formula , represents the first , The sample point and the current , The Euclidean distance between sample points is represents the cutoff distance, Represents a symbolic function.

[0010] In some embodiments, the determination of the maximum density peak sample point under different powers is specifically: dividing the actual power of the unit into intervals to obtain multiple unit power division intervals; based on the density value, selecting the maximum density peak sample point in the unit power division interval.

[0011] In some embodiments, the multivariate regression modeling of the characteristic sample point set to generate the thermoelectric conversion efficiency curve of the unit is specifically as follows: the actual power of the unit in the characteristic sample point set is taken as the independent variable, the inlet steam heat in the characteristic sample point set is taken as the dependent variable, and the least squares criterion is used to determine the multivariate linear regression model between the two to determine the thermoelectric conversion efficiency curve of the unit.

[0012] In a second aspect, the present invention provides a system for estimating a thermal efficiency curve of a coal-fired power generation unit; A system for estimating thermal efficiency curve of a coal-fired power generation unit, comprising: The heat estimation module is configured to: obtain the main steam temperature, main steam pressure, main steam flow rate and actual power of the coal-fired power generation unit, calculate the main steam intake ratio according to the main steam temperature and the main steam pressure; determine the steam intake heat of the steam turbine according to the main steam intake ratio and the main steam flow rate; The density peak value calculation module is configured to: form a two-dimensional sample point set based on the inlet steam heat and the actual power of the unit, calculate the density value of each sample point in the two-dimensional sample point set, and determine the maximum density peak value sample point under different powers to construct a characteristic sample point set; The thermoelectric efficiency curve estimation module is configured to: perform multivariate regression modeling on the characteristic sample point set to generate a thermoelectric conversion efficiency curve of the unit.

[0013] In a third aspect, the present invention provides an electronic device; An electronic device comprises a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above-mentioned method for estimating the thermal efficiency curve of a coal-fired power generation unit.

[0014] In a fourth aspect, the present invention provides a computer-readable storage medium; A computer-readable storage medium stores a computer program / instruction, which, when executed by a processor, implements the steps of the above-mentioned method for estimating the thermal efficiency curve of a coal-fired power generation unit.

[0015] In a fifth aspect, the present invention provides a computer program product; A computer program product comprises a computer program / instruction, which, when executed by a processor, implements the steps of the above-mentioned method for estimating the thermal efficiency curve of a coal-fired power generation unit.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The technical solution provided by the present invention estimates the thermoelectric efficiency curve of the coal-fired power generation unit based on the unit operation data that can reflect the actual operating status of the unit, which can effectively make up for the shortcomings of the design value in various applications and is more in line with the actual operating status of the coal-fired power generation unit.

[0017] 2. The technical solution provided by the present invention can effectively reveal the real thermoelectric conversion efficiency of the unit and provide support for optimizing the operation mode of the unit. Optimizing the unit based on this can reduce the unit's unit carbon emissions and increase the unit's revenue.

[0018] 3. The technical solution provided by the present invention requires fewer unit parameters and less reliance on process knowledge, and has the significant advantage of being easy to implement, which is of positive significance for the promotion and application of this technical solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings in the specification, which constitute 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 improper limitations on the present invention.

[0020] Figure 1 A schematic diagram of a flow chart of a method for estimating a thermal efficiency curve of a coal-fired power generation unit provided in an embodiment of the present invention; Figure 2 A schematic diagram of the trend of main steam temperature data provided by an embodiment of the present invention; Figure 3 A schematic diagram of the trend of main steam pressure data provided by an embodiment of the present invention; Figure 4 A schematic diagram of the trend of main steam flow data provided by an embodiment of the present invention; Figure 5 A schematic diagram of the trend of part of the unit load data provided by an embodiment of the present invention; Figure 6 A schematic diagram of a steam inlet heat sequence provided by an embodiment of the present invention; Figure 7 A schematic diagram of the actual power sequence of a unit provided in an embodiment of the present invention; Figure 8 A schematic diagram of a two-dimensional sample point set provided by an embodiment of the present invention; Fig. 9 An example diagram of a feature sample point set provided by an embodiment of the present invention; Fig.10 This is an example diagram of the estimation results of the thermoelectric efficiency curve provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0022] It should be noted that the terms used herein are only for describing specific embodiments, and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that the terms "include" and "have" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0023] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0024] Embodiment 1 At present, it is generally believed that the thermoelectric conversion efficiency of coal-fired power generation units is a fixed value, ignoring the impact of different loads on different thermoelectric conversion efficiencies, resulting in an increase in the unit carbon emissions of the unit; therefore, the present invention provides a method for estimating the thermoelectric efficiency curve of a coal-fired power generation unit, which is based on the unit operation data, estimates the steam inlet heat of the turbine, and calculates the density peak value of the estimated heat result and the actual power of the unit to obtain the density peak sample point, and then performs a multivariate regression analysis on the density peak point to obtain the estimation result of the thermoelectric conversion efficiency curve.

[0025] Next, combine Figure 1-Figure 10 , a method for estimating a thermal efficiency curve of a coal-fired power generation unit disclosed in this embodiment is described in detail. The method for estimating a thermal efficiency curve of a coal-fired power generation unit comprises: S1. Obtain the main steam temperature data of the coal-fired power generation unit at a fixed sampling period , Main steam pressure data , Main steam flow data And the actual power data of the unit .

[0026] For the coal-fired power generation unit whose thermoelectric conversion efficiency curve is to be estimated, the upper and lower limits of the unit power are obtained to ensure that the above long-term operation data includes the minimum power generation power during normal operation of the unit to the maximum power generation power of the unit, and lasts for a long time.

[0027] S2, use sliding average filter to filter the main steam temperature data , Main steam pressure data , Main steam flow data And the actual power data of the unit Perform smoothing filtering to obtain filtered main steam temperature data , Main steam pressure data , Main steam flow data And the actual power data of the unit .

[0028] Based on this, the above filtering process can reduce the impact of random fluctuations in the data on the estimation results.

[0029] Next, the main steam temperature is changed to Taking the sliding average filter as an example, the filtering process is further introduced, which is expressed as: ,

[0030] in, is the window width of the sliding average filter, is the sample ordinal number, The length of the data.

[0031] In this embodiment, , and They can be obtained according to the same principle as above.

[0032] Furthermore, in a specific implementation, the window width of the sliding smoothing filter should be appropriate to avoid over-smoothing and loss of inherent information in the data. In this step, the window width of the sliding smoothing filter is determined in combination with the characteristics of the coal-fired power generation process. For example, the coal-fired power generation unit needs to complete the actual operation requirements of the unit power control instruction within the specified response time of 60 seconds, and the process has two stages: a dynamic response process and a steady-state process. The window width is recommended to be 30 seconds.

[0033] S3, according to the filtered main steam temperature data And filtered main steam pressure data , calculate the main steam inlet ratio.

[0034] Specifically, first, according to the filtered main steam pressure data The ideal gas part and the residual gas part of the dimensionless Gibbs free energy are calculated based on the ratio of the ideal gas part and the residual gas part of the dimensionless Gibbs free energy, respectively; then, based on the ideal gas part and the residual gas part of the dimensionless Gibbs free energy, the filtered main steam temperature data are combined , calculate the main steam inlet ratio.

[0035] Exemplary, dimensionless ideal gas part of the Gibbs free energy It is expressed as: ; Residual gas part of the dimensionless Gibbs free energy It is expressed as: ; In the formula, Represents the first proportionality coefficient, whose value is ; Indicates the pressure constant, the value is 1Mpa; represents the first coefficient, represents the first index, represents the second coefficient, represents the second index, i Indicates an ordinal number.

[0036] The main steam inlet ratio is expressed as: ; In the formula, represents the gas constant of ordinary water, ; Represents the second proportional coefficient, whose value is ; Represents the temperature constant, and its value is 540K.

[0037] Here, according to the conclusions in the IAPWS 1997 Announcement on the Calculation Formulas for Thermodynamic Properties of Industrial Water and Steam, , The value of can be found in Table 1. , and Please refer to Table 2.

[0038] Table 1

[0039] Table 2

[0040] S4. Determine the steam inlet heat of the turbine based on the main steam inlet ratio and main steam flow rate.

[0041] For example, the inlet steam heat of the steam turbine is expressed as: ; In the formula, represents the unit mass flow rate of the inlet steam, The value of is the main steam flow The value converted to Kg / h (kilograms per hour).

[0042] S5. A two-dimensional sample point set is formed based on the inlet steam heat and the actual power of the unit, the density value of each sample point in the two-dimensional sample point set is calculated, and the maximum density peak sample point under different powers is determined to construct a characteristic sample point set.

[0043] Here, if Figure 8 As shown in the figure, with the steam inlet heat as the vertical axis and the actual power of the unit as the horizontal axis, the steam inlet heat at the same time is associated with the actual power of the unit to form a two-dimensional sample point set. The thermal power conversion efficiency curve is estimated using the steam inlet heat and the actual power of the unit, avoiding the uncertainty of the thermal power conversion efficiency curve estimation result caused by coal quality fluctuations.

[0044] For example, for a two-dimensional sample point set For example, the density value of each sample point is expressed as: ; In the formula, Represents the first two-dimensional sample point set , The sample point and the current , The Euclidean distance between sample points is represents the cutoff distance, represents a symbolic function, when Greater than or equal to hour ,when Less than hour .

[0045] Furthermore, the maximum density peak sample points under different powers are determined including: (1) The actual power generated by the unit is divided into intervals to obtain multiple unit power division intervals.

[0046] In order to ensure that the selection of the maximum density peak sample point can not only ensure the significance of the density peak sample point, but also have the distinguishability of power changes, therefore, in this embodiment, the width of the power division interval is determined in combination with the characteristics of the unit power control command amplitude.

[0047] Specifically, the amplitude of the change in the unit power control command should be significantly larger than the random fluctuation in the actual power data. The width of the power division interval can be determined based on the dead zone width of the power control command adopted by the generator set, the random fluctuation operating range of the actual power data, and the sum of 6 times the standard deviation of the measurement noise in the actual power data. Among them, the standard deviation of the measurement noise in the actual power data is determined based on the 3-Sigma principle.

[0048] For example, the dead zone width of power control instructions currently commonly used by generator sets is 1MW, the random fluctuation operating range of actual power data is 1MW, and the standard deviation of measurement noise in 6 times the actual power data is 0.7MW, then the width of the power division interval can be 2.7MW.

[0049] (2) Based on the density value of each sample point, the sample point with the maximum density peak value is selected within the unit power division interval to form a characteristic sample point set; it is expressed as: ; in, and Respectively represent The upper and lower limits of the power division interval of each unit, Represents a function that finds the independent variable that maximizes the function.

[0050] Based on this, by selecting the maximum density peak sample point, the influence of the corresponding two-dimensional sample points on the estimation results under abnormal operating conditions, manual operation, random fluctuations, etc. can be avoided.

[0051] S6. Perform multivariate regression modeling on the characteristic sample point set to generate the thermal-electric conversion efficiency curve of the unit.

[0052] Specifically, the actual power point of the unit in the characteristic sample point concentration is taken as the independent variable, and the steam inlet heat point in the characteristic sample point concentration is taken as the dependent variable. The least squares criterion is used to determine the multivariate linear regression model between the two, and the obtained model is the unit thermal electric conversion efficiency curve.

[0053] In this embodiment, in order to avoid overfitting and underfitting, the model order can be set to 2nd to 3rd order.

[0054] Furthermore, the thermoelectric conversion efficiency curve can be expressed as: ; In the formula, , , …, represents the regression model parameters.

[0055] Next, in order to prove the effectiveness of the solution described in this embodiment, the estimation of the thermal-electric conversion efficiency curve of a 200MW coal-fired unit is used as an example to carry out relevant experimental verification, and illustrate the specific effect of the method described in this embodiment in practical application. The specific process is as follows: Step 1: Obtain the main steam temperature of the unit with a sampling period of 1 second , Main steam pressure , Main steam flow And the actual power of the unit The running data for 30 consecutive days, some of the data obtained are as follows Figure 2-Figure 5 shown.

[0056] Step 2: Set the sliding average filter window width , the main steam temperature data, main steam pressure data, main steam flow data and actual power data of the unit are smoothed and filtered respectively to obtain the filtered main steam temperature data , Main steam pressure data , Main steam flow data And the actual power data of the unit .

[0057] Step 3: According to the filtered main steam temperature data And main steam pressure data , the main steam intake ratio is calculated , and then the main steam intake And filtered main steam flow data , the steam inlet heat series of the steam turbine is calculated ,like Figure 6 shown; contrast Figure 6 and Figure 7 From the trend of the middle curve, we can find that the trends of the two curves are similar, which shows that the obtained steam inlet heat sequence is reasonable.

[0058] Step 4: Inlet steam heat sequence and the actual power sequence Form a two-dimensional sample point set ,like Figure 8 As shown by the blue dots in the middle; the actual power range of the unit is divided into 2.7MW, and then the maximum density peak sample points in each actual power range are determined, and all the maximum density peak sample points obtained form a characteristic sample point set, as shown in Fig. 9 As shown by the red dot; Step 5: Perform a multivariate regression model on the obtained characteristic sample point set to obtain the thermoelectric conversion efficiency curve of the unit, and its analytical expression is: .

[0059] The thermoelectric conversion efficiency curve of the unit is as follows Fig.10 As shown by the black curve in Fig.10 From the obtained thermoelectric conversion efficiency curve, it can be seen that the thermoelectric conversion efficiency of the coal-fired power generation unit in the low load section is slightly higher than that in the high load section.

[0060] Embodiment 2 This embodiment discloses a system for estimating a thermal efficiency curve of a coal-fired power generation unit, comprising: The heat estimation module is configured to: obtain the main steam temperature, main steam pressure, main steam flow rate and actual power of the coal-fired power generation unit, calculate the main steam intake ratio according to the main steam temperature and the main steam pressure; determine the steam intake heat of the steam turbine according to the main steam intake ratio and the main steam flow rate; The density peak value calculation module is configured to: form a two-dimensional sample point set based on the inlet steam heat and the actual power of the unit, calculate the density value of each sample point in the two-dimensional sample point set, and determine the maximum density peak value sample point under different powers to construct a characteristic sample point set; The thermoelectric efficiency curve estimation module is configured to: perform multivariate regression modeling on the characteristic sample point set to generate a thermoelectric conversion efficiency curve of the unit.

[0061] It should be noted that the heat estimation module, density peak calculation module and thermoelectric efficiency curve estimation module correspond to the steps in Embodiment 1, and the examples and application scenarios implemented by the modules and the corresponding steps are the same, but are not limited to the contents disclosed in Embodiment 1. It should be noted that the modules as part of the system can be executed in a computer system such as a set of computer executable instructions.

[0062] Embodiment 3 Embodiment 3 of the present invention provides an electronic device, including a memory and a processor, and computer instructions stored in the memory and executed on the processor. When the computer instructions are executed by the processor, the steps of the above-mentioned method for estimating the thermal efficiency curve of a coal-fired power generation unit are completed.

[0063] Embodiment 4 Embodiment 4 of the present invention provides a computer-readable storage medium for storing computer instructions. When the computer instructions are executed by a processor, the steps of the above-mentioned method for estimating the thermal efficiency curve of a coal-fired power generation unit are completed.

[0064] Embodiment 5 Embodiment 5 of the present invention provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the steps of the above-mentioned method for estimating the thermal efficiency curve of a coal-fired power generation unit.

[0065] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks 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 produce 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.

[0066] 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.

[0067] These computer program instructions can also be loaded onto a computer or other programmable data processing device, and a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide 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.

[0068] The description of each embodiment in the above embodiments has different emphases. For parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for estimating the thermal efficiency curve of a coal-fired power generation unit, characterized in that: include: Obtain the main steam temperature, main steam pressure, main steam flow rate and actual power of the coal-fired power generation unit, calculate the main steam intake ratio according to the main steam temperature and the main steam pressure; determine the steam intake heat of the steam turbine according to the main steam intake ratio and the main steam flow rate; A two-dimensional sample point set is formed based on the inlet steam heat and the actual power of the unit, the density value of each sample point in the two-dimensional sample point set is calculated, and the maximum density peak sample point under different powers is determined to construct a characteristic sample point set; Multivariate regression modeling is performed on the characteristic sample point set to generate the thermoelectric conversion efficiency curve of the unit.

2. The method for estimating the thermal efficiency curve of a coal-fired power generation unit according to claim 1, characterized in that: Calculating the main steam intake ratio according to the main steam temperature and the main steam pressure includes: According to the ratio of the main steam pressure to the pressure constant, respectively calculating the ideal gas part and the residual gas part of the dimensionless Gibbs free energy; The main steam inlet ratio is calculated based on the ideal gas part and the residual gas part of the dimensionless Gibbs free energy in combination with the main steam temperature.

3. The method for estimating the thermal efficiency curve of a coal-fired power generation unit according to claim 1, characterized in that: Determining the steam inlet heat of the steam turbine according to the main steam inlet ratio and the main steam flow rate is specifically as follows: converting the main steam flow rate into units and multiplying it by the main steam inlet ratio to obtain the steam inlet heat of the steam turbine.

4. The method for estimating the thermal efficiency curve of a coal-fired power generation unit according to claim 1, characterized in that: The density value is expressed as: ； In the formula, Represents the first two-dimensional sample point set , The sample point and the current , The Euclidean distance between sample points is represents the cutoff distance, Represents a symbolic function.

5. The method for estimating the thermal efficiency curve of a coal-fired power generation unit according to claim 1, characterized in that: The method of determining the maximum density peak sample point under different powers specifically comprises: dividing the actual power of the unit into intervals to obtain a plurality of unit power division intervals; and selecting the maximum density peak sample point within the unit power division interval based on the density value.

6. The method for estimating the thermal efficiency curve of a coal-fired power generation unit according to claim 1, characterized in that: The method of performing multivariate regression modeling on the characteristic sample point set to generate the thermoelectric conversion efficiency curve of the unit is specifically as follows: taking the actual power of the unit in the characteristic sample point set as the independent variable, taking the inlet steam heat in the characteristic sample point set as the dependent variable, and using the least squares criterion to determine the multivariate linear regression model between the two to determine the thermoelectric conversion efficiency curve of the unit.

7. A system for estimating the thermal efficiency curve of a coal-fired power generation unit, characterized in that: include: The heat estimation module is configured to: obtain the main steam temperature, main steam pressure, main steam flow rate and actual power of the coal-fired power generation unit, calculate the main steam intake ratio according to the main steam temperature and the main steam pressure; determine the steam intake heat of the steam turbine according to the main steam intake ratio and the main steam flow rate; The density peak value calculation module is configured to: form a two-dimensional sample point set based on the inlet steam heat and the actual power of the unit, calculate the density value of each sample point in the two-dimensional sample point set, and determine the maximum density peak value sample point under different powers to construct a characteristic sample point set; The thermoelectric efficiency curve estimation module is configured to: perform multivariate regression modeling on the characteristic sample point set to generate a thermoelectric conversion efficiency curve of the unit.

8. An electronic device comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method for estimating the thermal efficiency curve of a coal-fired power generation unit according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instruction is executed by a processor, the steps of the method for estimating the thermal efficiency curve of a coal-fired power generation unit described in any one of claims 1 to 6 are implemented.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instruction is executed by a processor, the steps of the method for estimating the thermal efficiency curve of a coal-fired power generation unit described in any one of claims 1 to 6 are implemented.

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