A feature-based pump station unit characteristic operating point matching curve method and system

Abstract

The application provides a feature-based pump station unit characteristic working point matching curve method and system. The method comprises the following steps: selecting a quadratic function as a mathematical description curve of pump station unit characteristics; constructing a history fitting curve of pump station unit characteristics according to the abscissa, ordinate and quadratic term coefficient of the vertex of the mathematical description curve; solving the parameters of the history fitting curve based on the history data points; when a deviation is found between the actual working point and the history characteristic curve, fixing the trend of the history fitting curve, updating the remaining geometric characteristic parameters of the history fitting curve, obtaining a working point matching curve, converting the working point matching curve into the form of a quadratic function, obtaining a matching updated mathematical description curve, and obtaining the frequency of the pump station unit according to the flow of the scheduling water quantity demand and the parameters of the matching updated mathematical description curve. The application directly uses the pump station operation data at the current time to match the characteristic curve with the actual working point.

Description

Technical Field

[0001] This invention belongs to the field of industrial automation, and in particular relates to a feature-based method and system for matching the characteristic operating point curve of a pump station unit. Background Technology

[0002] The frequency-flow characteristic curve of a pumping station unit is a graph describing the relationship between the flow output of the pumping station at different frequencies. Once the frequency-flow curve of the unit is determined, as the operating frequency of the pumping station unit increases, its flow output will also increase accordingly; similarly, as the frequency decreases, the flow output will also decrease accordingly.

[0003] During operation, the pump station unit exhibits a certain flow saturation phenomenon in its water volume-frequency characteristics. That is, as the frequency increases to a certain level, the output water volume decreases with the rate of increase in frequency. Therefore, a quadratic function curve Q = af can be used. 2 The section with +bf+c describes the characteristic relationship between the pump station's frequency and flow rate.

[0004] During the project management process, it is necessary to base the historical operating points of the pumping station on (f1,Q1), (f2,Q2)...(f n Q n By determining the curve parameters a, b, and c that make the characteristic curve statistically closest to the historical operating point, the water flow-frequency characteristics of the pumping station unit can be determined. During the operation of the pumping station, the pumps can be controlled based on the obtained water flow-frequency characteristics.

[0005] Due to various errors, the measured values ​​at historical operating points of the pumping station will deviate from the actual characteristic curve. Since the water flow-frequency characteristic of the pumping station unit is only a segment of a quadratic function, directly fitting historical data to determine the water flow-frequency characteristic of the pumping station unit will cause even slight changes in the historical operating points to lead to drastic changes in the obtained characteristic curve parameters a, b, and c, making it difficult to obtain a stable and usable unit characteristic curve. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention proposes a feature-based method for matching the characteristic operating point curve of a pumping station unit, thereby resolving these issues.

[0007] The first aspect of this invention discloses a feature-based method for matching the characteristic operating point curve of a pumping station unit, the method comprising:

[0008] Step S1: Obtain historical data on the frequency and flow rate of the pumping station, preprocess the historical data and perform data rationality analysis, and select data points in flow ranges with high credibility;

[0009] Step S2: Select a quadratic function as the mathematical description curve of the pump station unit characteristics; construct a historical fitting curve of the pump station unit characteristics based on the x-coordinate and y-coordinate of the vertex of the mathematical description curve; and solve for the parameters of the historical fitting curve based on the data points, i.e., the historical data, using the least squares method.

[0010] Step S3: When a deviation is found between the actual operating point and the historical characteristic curve, read the current actual operating point frequency and flow rate; based on the current actual operating point frequency and flow rate, fix the trend of the historical fitting curve, update the parameters of the historical fitting curve, i.e., the remaining geometric feature parameters, to obtain the operating point matching curve.

[0011] Step S4: Transform the working point matching curve into a quadratic function to obtain the matching updated mathematical description curve; based on the flow rate of the scheduled water demand, obtain the frequency of the pump station unit through the parameters of the matching updated mathematical description curve.

[0012] According to the method of the first aspect of the present invention, in step S2, the method of constructing a historical fitting curve of the pump station unit characteristics based on the abscissa and ordinate of the vertex of the mathematical description curve includes:

[0013] Q = a1(ff) vertex ) 2 +Q vertex

[0014] Where Q represents flow rate; f represents frequency; and a1 is the coefficient of the quadratic term in the mathematical description curve. The x-coordinate of the vertex; The ordinate of the vertex;

[0015] Where b1 is the coefficient of the linear term of the mathematical description curve; c1 is the constant term of the mathematical description curve.

[0016] According to the method of the first aspect of the present invention, in step S3, the method of fixing the trend of the historical fitting curve, updating the parameters of the historical fitting curve, and obtaining the working point matching curve includes:

[0017] If we choose to keep the aperture size and direction of the historical fitted curve constant, that is, let a1 remain unchanged, we can solve for the new f. vertex and Q vertex If the x-coordinate of the vertex of the historical fitted curve remains unchanged, that is, let f vertex Keeping them unchanged, solve for the new a1 and Q. vertex If the ordinate of the vertex of the historical fitted curve remains unchanged, that is, let Q... vertex Keeping them unchanged, solve for the new a1 and f. vertex .

[0018] According to the method of the first aspect of the present invention, in step S4, the method of obtaining the frequency of the pumping station unit by matching the parameters of the updated mathematical description curve based on the flow rate of the scheduled water demand includes:

[0019] If the flow rate Q of the water demand for scheduling a =Q0 + Δq, then we can find the answer.

[0020]

[0021] If the flow rate Q of the water demand for scheduling b =Q0-Δq, then we can find the answer.

[0022]

[0023] Where Q0 is the current actual operating point flow; Δq is Q a The difference from Q0; a2 is the coefficient of the quadratic term of the matched and updated mathematical description curve; b2 is the coefficient of the linear term of the matched and updated mathematical description curve; c2 is the constant term of the matched and updated mathematical description curve; f a The flow rate Q represents the water demand for water allocation. a When =Q0+Δq, the frequency of the pump station unit is obtained; f b The flow rate Q represents the water demand for water allocation. a The frequency of the pump station unit is obtained when Q0-Δq is equal to 0.

[0024] A second aspect of this invention discloses a feature-based system for matching the characteristic operating point curves of a pumping station unit, the system comprising:

[0025] The first processing module is configured to acquire historical data on the frequency and flow of the pumping station, preprocess the historical data and perform data rationality analysis, and select data points in flow ranges with high reliability.

[0026] The second processing module is configured to select a quadratic function as the mathematical description curve of the pump station unit characteristics; construct a historical fitting curve of the pump station unit characteristics based on the x-coordinate and y-coordinate of the vertex of the mathematical description curve; and solve for the parameters of the historical fitting curve using the least squares method based on the data points.

[0027] The third processing module is configured to, when a deviation is found between the actual operating point and the historical characteristic curve, read the frequency and flow of the current actual operating point; based on the frequency and flow of the current actual operating point, fix the trend of the historical fitting curve, update the parameters of the historical fitting curve, and obtain the operating point matching curve.

[0028] The fourth processing module is configured to convert the working point matching curve into a quadratic function to obtain a matching updated mathematical description curve; and to obtain the frequency of the pump station unit based on the flow rate of the scheduled water demand and the parameters of the matching updated mathematical description curve.

[0029] According to a system of a second aspect of the present invention, the method for constructing a historical fitting curve of pump station unit characteristics based on the abscissa and ordinate of the vertex of a mathematically described curve includes:

[0030] Q = a1(ff) vertex ) 2 +Q vertex

[0031] Where Q represents flow rate; f represents frequency; and a1 is the coefficient of the quadratic term in the mathematical description curve. The x-coordinate of the vertex; The ordinate of the vertex;

[0032] Where b1 is the coefficient of the linear term of the mathematical description curve; c1 is the constant term of the mathematical description curve.

[0033] According to the system of the second aspect of the present invention, the method of fixing the trend of the historical fitting curve, updating the parameters of the historical fitting curve, and obtaining the operating point matching curve includes:

[0034] If we choose to keep the aperture size and direction of the historical fitted curve constant, that is, let a1 remain unchanged, we can solve for the new f. vertex and Q vertex If the x-coordinate of the vertex of the historical fitted curve remains unchanged, that is, let f vertex Keeping them unchanged, solve for the new a1 and Q. vertex If the ordinate of the vertex of the historical fitted curve remains unchanged, that is, let Q... vertex Keeping them unchanged, solve for the new a1 and f. vertex .

[0035] According to a system of a second aspect of the present invention, the method for obtaining the frequency of the pumping station units by matching parameters of an updated mathematical description curve based on the flow rate of the scheduled water demand includes:

[0036] If the flow rate Q of the water demand for scheduling a =Q0 + Δq, then we can find the answer.

[0037]

[0038] If the flow rate Q of the water demand for scheduling b =Q0-Δq, then we can find the answer.

[0039]

[0040] Where Q0 is the current actual operating point flow; Δq is Q a The difference from Q0; a2 is the coefficient of the quadratic term of the matched and updated mathematical description curve; b2 is the coefficient of the linear term of the matched and updated mathematical description curve; c2 is the constant term of the matched and updated mathematical description curve; f a The flow rate Q represents the water demand for water allocation. a When =Q0+Δq, the frequency of the pump station unit is obtained; f b The flow rate Q represents the water demand for water allocation. a The frequency of the pump station unit is obtained when Q0-Δq is equal to 0.

[0041] A third aspect of this invention discloses an electronic device. The electronic device includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the steps of the feature-based method for matching the characteristic operating point curve of a pumping station unit according to any one of the first aspects of this disclosure.

[0042] A fourth aspect of this invention discloses a computer-readable storage medium. The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of a feature-based method for matching the characteristic operating point curve of a pumping station unit according to any one of the first aspects of this disclosure.

[0043] In summary, the beneficial effects of the solution proposed in this invention are as follows:

[0044] 1. The characteristic curve matches the actual real-time operating point, and when switching from manual control to automatic control, no logical errors will occur due to the excessive difference between the operating point and the unit's characteristic curve.

[0045] 2. It is highly adaptable and can ensure the effectiveness of the algorithm when switching from automatic control program to unit characteristic control at any time and any operating point.

[0046] 3. Easier parameter adjustment: In the functional form of this method, 'a' represents the opening direction and magnitude of the quadratic function, while 'f'... vertex and Q vertex This represents the position of the vertex. In contrast, in the form a, b, c, the values ​​of b and c may be affected by a, leading to increased correlation between parameters. Geometric feature transformation can reduce this correlation, making the parameters easier to understand and adjust independently.

[0047] 4. Practical Physical Significance: The functional form of this method intuitively expresses the geometric characteristics of a quadratic function, making it more suitable for describing the shape of the characteristic curves of pump station units. Compared to forms a, b, and c, a and f... vertex and Q vertexThe form is more in line with the engineering field's understanding and expression of geometric shapes. Geometric coefficients, such as the axis of symmetry f, are... vertex Vertical axis translation Q vertex The adjustments reflect the specific problems and needs encountered during the operation of the pumping station.

[0048] 5. Taking full account of historical data, the obtained unit characteristic curves have statistically significant accuracy. Attached Figure Description

[0049] 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.

[0050] Figure 1 A flowchart illustrating a feature-based method for matching the characteristic operating point curve of a pumping station unit according to an embodiment of the present invention;

[0051] Figure 2 This is a historical fitting curve diagram according to an embodiment of the present invention;

[0052] Figure 3 This is a diagram illustrating the characteristic deviation of a generator unit according to an embodiment of the present invention.

[0053] Figure 4 A unit characteristic fitting curve diagram for the case of curve inversion according to an embodiment of the present invention;

[0054] Figure 5 This is a working point matching curve diagram according to an embodiment of the present invention;

[0055] Figure 6 This is a structural diagram of a feature-based pump station unit characteristic operating point matching curve system according to an embodiment of the present invention;

[0056] Figure 7 This is a structural diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0058] The first aspect of this invention discloses a feature-based method for matching the characteristic operating point curve of a pumping station unit. Figure 1 This is a flowchart of a feature-based method for matching the characteristic operating point curve of a pumping station unit according to an embodiment of the present invention, as shown below. Figure 1 As shown, the method includes:

[0059] Step S1: Obtain historical data on the frequency and flow rate of the pumping station, preprocess the historical data and perform data rationality analysis, and select data points in flow ranges with high credibility;

[0060] Step S2: Select a quadratic function as the mathematical description curve of the pump station unit characteristics; construct a historical fitting curve of the pump station unit characteristics based on the x-coordinate and y-coordinate of the vertex of the mathematical description curve; and solve for the parameters of the historical fitting curve using the least squares method based on the data points, i.e., the historical data points.

[0061] Step S3: When a deviation is found between the actual operating point and the historical characteristic curve, read the current actual operating point frequency and flow rate; based on the current actual operating point frequency and flow rate, fix the trend of the historical fitting curve, update the parameters of the historical fitting curve, i.e., the remaining geometric feature parameters, to obtain the operating point matching curve.

[0062] Step S4: Transform the working point matching curve into a quadratic function to obtain the matching updated mathematical description curve; based on the flow rate of the scheduled water demand, obtain the frequency of the pump station unit through the parameters of the matching updated mathematical description curve.

[0063] In step S1, historical data on the frequency and flow of the pumping station are acquired, and the historical data are preprocessed and analyzed for data rationality. Data points in flow ranges with high reliability are selected.

[0064] Specifically, the raw data points of the pump frequency and flow rate are obtained, and the data are preprocessed. The processed data points are those that meet the actual needs and satisfy the stable flow output, head output and operating frequency of a specific model of pump under similar historical scheduling instructions.

[0065] Analyze the rationality of the data points: Compare the obtained data with the recently calculated characteristic curves of this type of water pump to determine whether the pump is within its normal operating range. If an anomaly is found, continuous data collection is required to determine whether the anomaly is a single point or a fault in the pump itself. Perform density analysis on the distribution of the collected data points to select flow ranges with higher reliability. After the data rationality is deemed satisfactory, save the data: (f1,Q1), (f2,Q2)…(f 20 Q 20 (This contains 20 historical data entries.)

[0066] In step S2, a quadratic function is selected as the mathematical description curve of the pump station unit characteristics; a historical fitting curve of the pump station unit characteristics is constructed based on the x-coordinate and y-coordinate of the vertex of the mathematical description curve; and the parameters of the historical fitting curve are solved using the least squares method based on the data points.

[0067] In some embodiments, in step S2, the method for constructing a historical fitting curve of the pump station unit characteristics based on the abscissa and ordinate of the vertex of the mathematical description curve includes:

[0068] Q = a1(ff) vertex ) 2 +Q vertex

[0069] Where Q represents flow rate; f represents frequency; and a1 is the coefficient of the quadratic term in the mathematical description curve. The x-coordinate of the vertex; The ordinate of the vertex;

[0070] Where b1 is the coefficient of the linear term of the mathematical description curve; c1 is the constant term of the mathematical description curve.

[0071] Specifically, we choose the quadratic function Q = a1f 2 +b1f+c1 serves as the mathematical description curve of the pump station unit characteristics; however, the parameters of this equation will change drastically during the subsequent characteristic curve update process, as shown in Table 1.

[0072] Table 1

[0073] a b c Historical characteristic parameters -7.43 832.62 -19254.67 Update feature parameters 7.92 -475.14 8519.46

[0074] To avoid this situation, perform a geometric feature transformation: keep a1 unchanged, and make and Transform the quadratic function into Q = a1(ff) vertex ) 2 +Q vertex f here vertex and Q vertex Let x and y represent the x and y coordinates of the vertex of the parabola, respectively. a1 is the coefficient of the quadratic term, f represents the frequency, and Q represents the flow rate.

[0075] Substitute the data points (f1, Q1), (f2, Q2)...(f 20 Q 20 ), where f i Q represents the frequency of the i-th data point. i Let represent the flow rate of the i-th data point. The objective function is the sum of squared differences between the actual observations and the model predictions. The parameters that best fit the data are found by minimizing the objective function. Specifically, this is expressed as:

[0076] By differentiating the objective function, we obtain information about the geometric characteristic parameters a1 and f. vertex Q vertex The system of equations:

[0077]

[0078] By setting the derivative to zero and solving this system of equations, we can obtain the optimal set of parameters.

[0079] At this point, the unit characteristics are Q = a1(ff) vertex ) 2 +Q vertex express, Figure 2 This is a historical fitting curve plot determined based on historical data.

[0080] In step S3, when a deviation is found between the actual operating point and the historical characteristic curve, the frequency and flow rate of the current actual operating point are read; based on the frequency and flow rate of the current actual operating point, the trend of the historical fitting curve is fixed, the parameters of the historical fitting curve are updated, and the operating point matching curve is obtained.

[0081] In some embodiments, in step S3, the method of fixing the trend of the historical fitting curve, updating the parameters of the historical fitting curve, and obtaining the operating point matching curve includes:

[0082] If we choose to keep the aperture size and direction of the historical fitted curve constant, that is, let a1 remain unchanged, we can solve for the new f. vertex and Q vertex If the x-coordinate of the vertex of the historical fitted curve remains unchanged, that is, let f vertex Keeping them unchanged, solve for the new a1 and Q. vertex If the ordinate of the vertex of the historical fitted curve remains unchanged, that is, let Q... vertex Keeping them unchanged, solve for the new a1 and f. vertex .

[0083] Specifically, when a deviation is found between the actual operating point and the historical characteristic curve, the characteristic curve is updated, and the historical unit characteristic deviation diagram is shown below. Figure 3 As shown.

[0084] Read the current operating point frequency and flow rate [f0:{}, Q0:{}], where f0 represents the set of current operating point frequency values ​​and Q0 represents the set of current operating point flow rate values. If simply updating parameters without fixing the curve's direction, the updated curve will only satisfy the degree of fit and cannot indicate the unit's saturation characteristic trend. Figure 4 The diagram shows the case where the curve is inverted, therefore a single geometric feature must be fixed during the update.

[0085] If we choose to keep the aperture size and direction of the historical fitted curve constant, that is, let a1 remain unchanged, we can solve for the new f. vertex and Q vertex If the x-coordinate of the vertex of the historical fitted curve remains unchanged, that is, let f vertex Keeping them unchanged, solve for the new a1 and Q. vertex If the ordinate of the vertex of the historical fitted curve remains unchanged, that is, let Q... vertex Keeping them unchanged, solve for the new a1 and f. vertex .

[0086] For example, if the opening size remains unchanged, then a1 is kept constant, and f is adjusted. vertex and Q vertex The existing data is added to the current data to form a new data combination, which is then input. The values ​​of the changed geometric parameters are calculated using the least squares method. The objective function is defined as the sum of squared errors of the characteristic curve passing through the current operating point. Minimizing this objective function means that the characteristic curve will pass through the current operating point as much as possible, ensuring the stability and reliability of the system operation. The objective function is specifically expressed here as follows:

[0087] By differentiating the objective function, we obtain information about the geometric characteristic parameters f. vertex2 Q vertex2 The system of equations:

[0088]

[0089] By setting the derivative to zero and solving this system of equations, we can obtain the optimal parameters. Figure 5 Match the curve to the root working point.

[0090] The parameter variations are shown in Table 2.

[0091] a <![CDATA[f vertex2 ]]> <![CDATA[Q vertex2 ]]> Historical characteristic parameters -7.42 56.04 4077.98 Update feature parameters 7.92 30.00 1393.1

[0092] To clarify the physical meaning of geometric adjustments: geometric coefficients such as the axis of symmetry f vertex Vertical axis translation Q vertex The adjustments reflect specific problems and needs during the operation of the pumping station and have physical significance.

[0093] For example, by shifting the characteristic curve downwards (reducing Q) vertex This can reduce the flow rate pumped out by the unit at the same frequency, which means that the flow rate is reduced at the same frequency due to reasons such as unit aging; while reducing the value of a1, that is, making the parabola opening smaller, indicates that the flow rate changes more slowly in a certain frequency range, which may reflect a decrease in the agility of unit control in that range, or suggest that the flow rate regulation is limited in certain frequency ranges, which may require further inspection and maintenance.

[0094] In step S4, the operating point matching curve is transformed into a quadratic function to obtain the matching updated mathematical description curve; based on the flow rate of the scheduled water demand, the frequency of the pump station unit is obtained through the parameters of the matching updated mathematical description curve.

[0095] In some embodiments, in step S4, the method for obtaining the frequency of the pumping station units by matching the parameters of the updated mathematical description curve based on the flow rate of the scheduled water demand includes:

[0096] If the flow rate Q of the water demand for scheduling a =Q0 + Δq, then we can find the answer.

[0097]

[0098] If the flow rate Q of the water demand for scheduling b =Q0-Δq, then we can find the answer.

[0099]

[0100] Where Q0 is the current actual operating point flow; Δq is Q a The difference from Q0; a2 is the coefficient of the quadratic term of the matched and updated mathematical description curve; b2 is the coefficient of the linear term of the matched and updated mathematical description curve; c2 is the constant term of the matched and updated mathematical description curve; f a The flow rate Q represents the water demand for water allocation. a When =Q0+Δq, the frequency of the pump station unit is obtained; f b The flow rate Q represents the water demand for water allocation. a The frequency of the pump station unit is obtained when Q0-Δq is equal to 0.

[0101] Specifically, the mathematical description curve for the matching update is Q = a2f 2 +b²f+c², where a²=a², b²=-2a²f vertex2 c2=a2f vertex2 2 +Q vertex2 .

[0102] The pump station's scheduling needs are guided by characteristic parameters that conform to the current operating conditions. These needs include increases or decreases in water demand from water plants along the pipeline, requiring adjustments to the pump station's flow rate, such as Q0 = a²f. 2 +b2f+c2 is used to adjust the unit frequency and thus change the flow rate.

[0103] If the flow rate Q of the water demand for scheduling a =Q0 + Δq, then we can find the answer.

[0104] Qa It must be greater than Q0;

[0105] If the flow rate Q of the water demand for scheduling b =Q0-Δq, then we can find the answer.

[0106] Q b It must be less than Q0;

[0107] The above ensures the continuity of the control process and the consistency of the logic.

[0108] In summary, the beneficial effects of the solution proposed in this invention are as follows:

[0109] 1. The characteristic curve matches the actual real-time operating point, and when switching from manual control to automatic control, no logical errors will occur due to the excessive difference between the operating point and the unit's characteristic curve.

[0110] 2. It is highly adaptable and can ensure the effectiveness of the algorithm when switching from automatic control program to unit characteristic control at any time and any operating point.

[0111] 3. Easier parameter adjustment: In the functional form of this method, 'a' represents the opening direction and magnitude of the quadratic function, while 'f'... vertex and Q vertex This represents the position of the vertex. In contrast, in the form a, b, c, the values ​​of b and c may be affected by a, leading to increased correlation between parameters. Geometric feature transformation can reduce this correlation, making the parameters easier to understand and adjust independently.

[0112] 4. Practical Physical Significance: The functional form of this method intuitively expresses the geometric characteristics of a quadratic function, making it more suitable for describing the shape of the characteristic curves of pump station units. Compared to forms a, b, and c, a and f... vertex and Q vertex The form is more in line with the engineering field's understanding and expression of geometric shapes. Geometric coefficients, such as the axis of symmetry f, are... vertex Vertical axis translation Q vertex The adjustments reflect the specific problems and needs encountered during the operation of the pumping station.

[0113] 5. Taking full account of historical data, the obtained unit characteristic curves have statistically significant accuracy.

[0114] The second aspect of the present invention discloses a feature-based pump station unit characteristic operating point matching curve system. Figure 6 This is a structural diagram of a feature-based pump station unit characteristic operating point matching curve system according to an embodiment of the present invention; as shown. Figure 6 As shown, the system 100 includes:

[0115] The first processing module 101 is configured to acquire historical data of frequency and flow of the pumping station, preprocess the historical data and perform data rationality analysis, and select data points in flow ranges with high credibility.

[0116] The second processing module 102 is configured to select a quadratic function as the mathematical description curve of the pump station unit characteristics; construct a historical fitting curve of the pump station unit characteristics based on the x-coordinate and y-coordinate of the vertex of the mathematical description curve; and solve the parameters of the historical fitting curve using the least squares method based on the data points.

[0117] The third processing module 103 is configured to, when a deviation is found between the actual operating point and the historical characteristic curve, read the frequency and flow of the current actual operating point; based on the frequency and flow of the current actual operating point, fix the trend of the historical fitting curve, update the parameters of the historical fitting curve, and obtain the operating point matching curve.

[0118] The fourth processing module 104 is configured to convert the working point matching curve into a quadratic function to obtain a matching updated mathematical description curve; and to obtain the frequency of the pump station unit based on the flow rate of the scheduled water demand and the parameters of the matching updated mathematical description curve.

[0119] According to the system of the second aspect of the present invention, the first processing module 101 is specifically configured to acquire the original data points of the pump frequency and flow rate, preprocess the data, and the processed data points are points that meet the actual needs and satisfy the stable flow output, head output and operating frequency of a specific model of pump under similar historical scheduling instructions.

[0120] Analyze the rationality of the data points: Compare the obtained data with the recently calculated characteristic curves of this type of water pump to determine whether the pump is within its normal operating range. If an anomaly is found, continuous data collection is required to determine whether the anomaly is a single point or a fault in the pump itself. Perform density analysis on the distribution of the collected data points to select flow ranges with higher reliability. After the data rationality is deemed satisfactory, save the data: (f1,Q1), (f2,Q2)...(f 20 Q 20 (This contains 20 historical data entries.)

[0121] According to a system of a second aspect of the present invention, the second processing module 102 is specifically configured such that the method for constructing a historical fitting curve of the pump station unit characteristics based on the abscissa and ordinate of the vertex of the mathematical description curve includes:

[0122] Q = a1(ff) vertex ) 2 +Q vertex

[0123] Where Q represents flow rate; f represents frequency; and a1 is the coefficient of the quadratic term in the mathematical description curve. The x-coordinate of the vertex; The ordinate of the vertex;

[0124] Where b1 is the coefficient of the linear term of the mathematical description curve; c1 is the constant term of the mathematical description curve.

[0125] Specifically, we choose the quadratic function Q = a1f 2 +b1f+c1 serves as the mathematical description curve of the pump station unit characteristics; however, the parameters of this equation will change drastically during the subsequent characteristic curve update process, as shown in Table 1.

[0126] Table 1

[0127] <![CDATA[a1]]> <![CDATA[b1]]> <![CDATA[c1]]> Historical characteristic parameters -7.43 832.62 -19254.67 Update feature parameters 7.92 -475.14 8519.46

[0128] To avoid this situation, perform a geometric feature transformation: keep a1 unchanged, and make and Transform the quadratic function into Q = a1(ff) vertex ) 2 +Q vertex f here vertex and Q vertex Let x and y represent the x and y coordinates of the vertex of the parabola, respectively. a1 is the coefficient of the quadratic term, f represents the frequency, and Q represents the flow rate.

[0129] Substitute the data points (f1, Q1), (f2, Q2)...(f 20 Q 20 ), where f i Q represents the frequency of the i-th data point. i Let represent the flow rate of the i-th data point. The objective function is the sum of squared differences between the actual observations and the model predictions. The parameters that best fit the data are found by minimizing the objective function. Specifically, this is expressed as:

[0130] By differentiating the objective function, we obtain information about the geometric characteristic parameters a1 and f. vertex Q vertex The system of equations:

[0131]

[0132] By setting the derivative to zero and solving this system of equations, we can obtain the optimal set of parameters.

[0133] At this point, the unit characteristics are Q = a1(ff) vertex ) 2 +Q vertex express, Figure 2This is a historical fitting curve plot determined based on historical data.

[0134] According to the system of the second aspect of the present invention, the third processing module 103 is specifically configured such that the method of fixing the trend of the historical fitting curve, updating the parameters of the historical fitting curve, and obtaining the working point matching curve includes:

[0135] If we choose to keep the aperture size and direction of the historical fitted curve constant, that is, let a1 remain unchanged, we can solve for the new f. vertex and Q vertex If the x-coordinate of the vertex of the historical fitted curve remains unchanged, that is, let f vertex Keeping them unchanged, solve for the new a1 and Q. vertex If the ordinate of the vertex of the historical fitted curve remains unchanged, that is, let Q... vertex Keeping them unchanged, solve for the new a1 and f. vertex .

[0136] Specifically, when a deviation is found between the actual operating point and the historical characteristic curve, the characteristic curve is updated, and the historical unit characteristic deviation diagram is shown below. Figure 3 As shown.

[0137] Read the current operating point frequency and flow rate [f0:{}, Q0:{}], where f0 represents the set of current operating point frequency values ​​and Q0 represents the set of current operating point flow rate values. If simply updating parameters without fixing the curve's direction, the updated curve will only satisfy the degree of fit and cannot indicate the unit's saturation characteristic trend. Figure 4 The diagram shows the case where the curve is inverted, therefore a single geometric feature must be fixed during the update.

[0138] If we choose to keep the aperture size and direction of the historical fitted curve constant, that is, let a1 remain unchanged, we can solve for the new f. vertex and Q vertex If the x-coordinate of the vertex of the historical fitted curve remains unchanged, that is, let f vertex Keeping them unchanged, solve for the new a1 and Q. vertex If the ordinate of the vertex of the historical fitted curve remains unchanged, that is, let Q... vertex Keeping them unchanged, solve for the new a1 and f. vertex .

[0139] For example, if the opening size remains unchanged, then a1 is kept constant, and f is adjusted. vertex and Q vertex The existing data is added to the current data to form a new data combination, which is then input. The values ​​of the changed geometric parameters are calculated using the least squares method. The objective function is defined as the sum of squared errors of the characteristic curve passing through the current operating point. Minimizing this objective function means that the characteristic curve will pass through the current operating point as much as possible, ensuring the stability and reliability of the system operation. The objective function is specifically expressed here as follows:

[0140] By differentiating the objective function, we obtain information about the geometric characteristic parameters f. vertex2 Q vertex2 The system of equations:

[0141]

[0142] By setting the derivative to zero and solving this system of equations, we can obtain the optimal parameters. Figure 5 Match the curve to the root working point.

[0143] The parameter variations are shown in Table 2.

[0144] a <![CDATA[f vertex2 ]]> <![CDATA[Q vertex2 ]]> Historical characteristic parameters -7.42 56.04 4077.98 Update feature parameters 7.92 30.00 1393.1

[0145] To clarify the physical meaning of geometric adjustments: geometric coefficients such as the axis of symmetry f vertex Vertical axis translation Q vertex The adjustments reflect specific problems and needs during the operation of the pumping station and have physical significance.

[0146] For example, by shifting the characteristic curve downwards (reducing Q) vertex This can reduce the flow rate pumped out by the unit at the same frequency, which means that the flow rate is reduced at the same frequency due to reasons such as unit aging; while reducing the value of a1, that is, making the parabola opening smaller, indicates that the flow rate changes more slowly in a certain frequency range, which may reflect a decrease in the agility of unit control in that range, or suggest that the flow rate regulation is limited in certain frequency ranges, which may require further inspection and maintenance.

[0147] According to the system of the second aspect of the present invention, the fourth processing module 104 is specifically configured such that the method for obtaining the frequency of the pumping station units by matching the parameters of an updated mathematical description curve based on the flow rate of the scheduled water demand includes:

[0148] If the flow rate Q of the water demand for scheduling a =Q0 + Δq, then we can find the answer.

[0149]

[0150] If the flow rate Q of the water demand for scheduling b =Q0-Δq, then we can find the answer.

[0151]

[0152] Where Q0 is the current actual operating point flow; Δq is Q aThe difference from Q0; a2 is the coefficient of the quadratic term of the matched and updated mathematical description curve; b2 is the coefficient of the linear term of the matched and updated mathematical description curve; c2 is the constant term of the matched and updated mathematical description curve; f a The flow rate Q represents the water demand for water allocation. a When =Q0+Δq, the frequency of the pump station unit is obtained; f b The flow rate Q represents the water demand for water allocation. a The frequency of the pump station unit is obtained when Q0-Δq is equal to 0.

[0153] Specifically, the mathematical description curve for the matching update is Q = a2f 2 +b²f+c², where a²=a², b²=-2a²f vertex2 c2=a2f vertex2 2 +Q vertex2 .

[0154] The pump station's scheduling needs are guided by characteristic parameters that conform to the current operating conditions. These needs include increases or decreases in water demand from water plants along the pipeline, requiring adjustments to the pump station's flow rate, such as Q0 = a²f. 2 +b2f+c2 is used to adjust the unit frequency and thus change the flow rate.

[0155] If the flow rate Q of the water demand for scheduling a =Q0 + Δq, then we can find the answer.

[0156] Q a It must be greater than Q0;

[0157] If the flow rate Q of the water demand for scheduling b =Q0-Δq, then we can find the answer.

[0158] Q b It must be less than Q0;

[0159] The above ensures the continuity of the control process and the consistency of the logic.

[0160] A third aspect of this invention discloses an electronic device. The electronic device includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the steps of the feature-based method for matching the characteristic operating point curve of a pumping station unit according to any one of the first aspects of this invention.

[0161] Figure 7 This is a structural diagram of an electronic device according to an embodiment of the present invention, such as... Figure 7As shown, the electronic device includes a processor, memory, communication interface, display screen, and input device connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, Near Field Communication (NFC), or other technologies. The display screen can be an LCD screen or an e-ink screen. The input device can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the device's casing, or an external keyboard, touchpad, or mouse.

[0162] Those skilled in the art will understand that Figure 7 The structure shown is merely a structural diagram of the part related to the technical solution of this disclosure and does not constitute a limitation on the electronic device to which the solution of this application is applied. The specific electronic device may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0163] A fourth aspect of this invention discloses a computer-readable storage medium. The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of a feature-based method for matching the characteristic operating point of a pumping station unit according to any one of the first aspects of this invention.

[0164] Please note that the technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments have been described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. The above embodiments only illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A feature-based method for matching the characteristic operating point curve of a pumping station unit, characterized in that, The method includes: Step S1: Obtain historical data on the frequency and flow rate of the pumping station, preprocess the historical data and perform data rationality analysis, and select data points in flow ranges with high credibility; Step S2: Select a quadratic function as the mathematical description curve of the pump station unit characteristics; construct a historical fitting curve of the pump station unit characteristics based on the x-coordinate and y-coordinate of the vertex of the mathematical description curve; and solve for the parameters of the historical fitting curve using the least squares method based on the data points. Step S3: When a deviation is found between the actual operating point and the historical characteristic curve, read the current actual operating point frequency and flow rate; based on the current actual operating point frequency and flow rate, fix the trend of the historical fitting curve, update the parameters of the historical fitting curve, and obtain the operating point matching curve. Step S4: Transform the working point matching curve into a quadratic function to obtain the matching updated mathematical description curve; based on the flow rate of the scheduled water demand, obtain the frequency of the pump station unit through the parameters of the matching updated mathematical description curve.

2. The feature-based method for matching the characteristic operating point curve of a pumping station unit according to claim 1, characterized in that, In step S2, the method for constructing the historical fitting curve of the pump station unit characteristics based on the x-coordinate and y-coordinate of the vertex of the mathematical description curve includes: Q=a1(f-f vertex ) 2 +Q vertex Where Q represents flow rate; f represents frequency; and a1 is the coefficient of the quadratic term in the mathematical description curve. The x-coordinate of the vertex; The ordinate of the vertex; Where b1 is the coefficient of the linear term of the mathematical description curve; c1 is the constant term of the mathematical description curve.

3. The feature-based method for matching the characteristic operating point curve of a pumping station unit according to claim 2, characterized in that, In step S3, the method of fixing the trend of the historical fitting curve, updating the parameters of the historical fitting curve, and obtaining the working point matching curve includes: If we choose to keep the aperture size and direction of the historical fitted curve constant, that is, let a1 remain unchanged, we can solve for the new f. vertex and Q vertex If the x-coordinate of the vertex of the historical fitted curve remains unchanged, that is, let f vertex Keeping them unchanged, solve for the new a1 and Q. vertex If the ordinate of the vertex of the historical fitted curve remains unchanged, that is, let Q... vertex Keeping them unchanged, solve for the new a1 and f. vertex .

4. The feature-based method for matching the characteristic operating point curve of a pumping station unit according to claim 1, characterized in that, In step S4, the method for obtaining the frequency of the pumping station units by matching the parameters of the updated mathematical description curve based on the flow rate of the scheduled water demand includes: If the flow rate Q of the water demand for scheduling a =Q0 + Δq, then we can find the answer. If the flow rate Q of the water demand for scheduling b =Q0-Δq, then we can find the answer. Where Q0 is the current actual operating point flow; Δq is Q a The difference from Q0; a2 is the coefficient of the quadratic term of the matched and updated mathematical description curve; b2 is the coefficient of the linear term of the matched and updated mathematical description curve; c2 is the constant term of the matched and updated mathematical description curve; f a The flow rate Q represents the water demand for water allocation. a When =Q0+Δq, the frequency of the pump station unit is obtained; f b The flow rate Q represents the water demand for water allocation. a The frequency of the pump station unit is obtained when Q0-Δq is equal to 0.

5. A feature-based system for matching the characteristic operating point curve of a pumping station unit, characterized in that, The system includes: The first processing module is configured to acquire historical data on the frequency and flow of the pumping station, preprocess the historical data and perform data rationality analysis, and select data points in flow ranges with high reliability. The second processing module is configured to select a quadratic function as the mathematical description curve of the pump station unit characteristics; construct a historical fitting curve of the pump station unit characteristics based on the x-coordinate and y-coordinate of the vertex of the mathematical description curve; and solve for the parameters of the historical fitting curve using the least squares method based on the data points. The third processing module is configured to, when a deviation is found between the actual operating point and the historical characteristic curve, read the frequency and flow of the current actual operating point; based on the frequency and flow of the current actual operating point, fix the trend of the historical fitting curve, update the parameters of the historical fitting curve, and obtain the operating point matching curve. The fourth processing module is configured to convert the working point matching curve into a quadratic function to obtain a matching updated mathematical description curve; and to obtain the frequency of the pump station unit based on the flow rate of the scheduled water demand and the parameters of the matching updated mathematical description curve.

6. The feature-based pump station unit characteristic operating point matching curve system according to claim 5, characterized in that, The method for constructing historical fitting curves of pump station unit characteristics based on the x and y coordinates of the vertex of the mathematical description curve includes: Q=a1(f-f vertex ) 2 +Q vertex Where Q represents flow rate; f represents frequency; and a1 is the coefficient of the quadratic term in the mathematical description curve. The x-coordinate of the vertex; The ordinate of the vertex; Where b1 is the coefficient of the linear term of the mathematical description curve; c1 is the constant term of the mathematical description curve.

7. The feature-based pump station unit characteristic operating point matching curve system according to claim 6, characterized in that, The method of fixing the trend of the historical fitting curve, updating the parameters of the historical fitting curve, and obtaining the operating point matching curve includes: If we choose to keep the aperture size and direction of the historical fitted curve constant, that is, let a1 remain unchanged, we can solve for the new f. vertex and Q vertex If the x-coordinate of the vertex of the historical fitted curve remains unchanged, that is, let f vertex Keeping them unchanged, solve for the new a1 and Q. vertex If the ordinate of the vertex of the historical fitted curve remains unchanged, that is, let Q... vertex Keeping them unchanged, solve for the new a1 and f. vertex .

8. The feature-based method for matching the characteristic operating point curve of a pumping station unit according to claim 5, characterized in that, The method for obtaining the frequency of the pumping station units by matching the parameters of the updated mathematical description curve based on the flow rate of the scheduled water demand includes: If the flow rate Q of the water demand for scheduling a =Q0 + Δq, then we can find the answer. If the flow rate Q of the water demand for scheduling b =Q0-Δq, then we can find the answer. Where Q0 is the current actual operating point flow; Δq is Q a The difference from Q0; a2 is the coefficient of the quadratic term of the matched and updated mathematical description curve; b2 is the coefficient of the linear term of the matched and updated mathematical description curve; c2 is the constant term of the matched and updated mathematical description curve; f a The flow rate Q represents the water demand for water allocation. a When =Q0+Δq, the frequency of the pump station unit is obtained; f b The flow rate Q represents the water demand for water allocation. a The frequency of the pump station unit is obtained when Q0-Δq is equal to 0.

9. An electronic device, characterized in that, The electronic device includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, it implements the steps in the feature-based pump station unit characteristic operating point matching curve method according to any one of claims 1 to 4.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the feature-based pump station unit characteristic operating point matching curve method according to any one of claims 1 to 4.

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