A partitioned air internal cooling quick selection calculation method for a pumped storage generator rotor

Abstract

The application discloses a kind of pumped storage generator rotor partition air internal cooling quick type selection calculation methods, belong to pumped storage power generation technical field, comprising the following steps: step 1, the equivalent heat dissipation area of air duct is calculated;Step 2, total air volume and the air volume of each air duct are calculated, whether the structure size of air duct is adjusted is judged;Step 3, the equivalent air velocity of air duct is calculated;Step 4, heat dissipation condition and temperature rise contrast coefficient are calculated;Step 5, by comparing the temperature rise and the measured temperature rise in historical unit, iteration optimization is completed to select type.The application can quickly complete the cooling calculation of rotor cooling structure in the preliminary type selection stage, shorten the rotor type selection design cycle, improve the type selection accuracy and reliability.

Description

Technical Field

[0001] This invention relates to the field of pumped storage power generation technology, and in particular to a rapid selection and calculation method for the rotor partitioning and internal cooling of a pumped storage generator. Background Technology

[0002] Pumped storage power generation motors operate at high speeds and generate significant centrifugal force, making it difficult to ensure their safety and reliability.

[0003] When selecting and designing rotor structures, it is necessary to ensure the safety of the rotor structure while meeting the ventilation and cooling requirements. In the past, due to the lack of preliminary selection criteria or process methods, it was impossible to obtain a reasonable cooling structure scheme in the preliminary design stage. It was necessary to spend a lot of resources to complete multiple rounds of calculation and verification, which was inefficient and ineffective.

[0004] To improve safety and reliability, existing technologies have developed hybrid ventilation cooling methods to improve the temperature difference of magnetic pole coils. Based on axial and radial hybrid ventilation cooling, this approach proposes a rotor magnetic pole partitioning and internal cooling method to enhance rotor cooling capacity, thereby reducing the amount of copper busbars used and the rotor diameter, fundamentally reducing centrifugal force. Application verification in actual power plants has shown a significant improvement in cooling capacity, with temperature rise 30% lower than traditional methods. However, in the selection and design of the unit, due to the lack of reference, multiple rounds of calculations and analyses are required, involving repeated structural modifications, optimizations, and iterative calculations and analyses. This results in a rotor selection and design cycle of up to one year, which is time-consuming and labor-intensive.

[0005] Chinese patent application document with publication number CN109818466A and publication date of May 28, 2019 discloses a method for manufacturing an electric motor rotor, an electric motor rotor, and an electric motor. The electric motor rotor includes a magnetic yoke and magnetic poles, and the magnetic poles include multiple magnetic steel units. The method for manufacturing the electric motor rotor includes the following steps: Step S1: Provide the magnetic yoke; Step S2: Based on the actual heat source distribution of the magnetic poles of the motor rotor before segmentation, the magnetic poles are segmented so that each magnetic steel unit is segmented into multiple magnetic steels of the same size, and the sizes of the magnetic steels segmented into each magnetic steel unit of the magnetic pole are not completely the same. Step S3: Assemble each of the segmented magnet units onto the magnetic yoke according to the results of the segmented design.

[0006] The manufacturing method for the motor rotor disclosed in this patent application involves segmenting the magnetic poles, which are hottest and generate concentrated heat, based on the actual heat source distribution before the magnetic poles are segmented. This effectively reduces eddy current losses in the magnetic poles, thereby reducing the heat generated and suppressing temperature rise, thus preventing irreversible demagnetization at high temperatures. However, the method still suffers from a long rotor selection and design cycle, and its selection accuracy and reliability are not ideal. Summary of the Invention

[0007] To overcome the shortcomings of the prior art, this invention provides a rapid selection calculation method for the rotor partitioned air-cooled structure of a pumped storage generator. This invention can quickly complete the cooling calculation of the rotor cooling structure in the preliminary selection stage, shorten the rotor selection design cycle, and improve the selection accuracy and reliability.

[0008] This invention is achieved through the following technical solution: A rapid selection and calculation method for the rotor partitioned air cooling of a pumped storage generator includes the following steps: Step 1: Calculate the equivalent heat dissipation area of ​​the air duct; Step 2: Calculate the total ventilation volume and the air volume of each duct, and determine whether to adjust the duct structure dimensions; Step 3: Calculate the equivalent wind speed in the duct; Step 4: Calculate the heat dissipation conditions and temperature rise comparison coefficient; Step 5: By comparing the calculated temperature rise with the measured temperature rise in historical units, iterative optimization is performed to complete the selection.

[0009] In step 1, the air duct includes an axial air duct between magnetic poles, a radial air duct between magnetic poles, and a cooling air duct inside the magnetic pole coil.

[0010] The equivalent heat dissipation area of ​​the axial air duct between the magnetic poles is calculated using Equation 1. A1 = N × (2 × (n × H + n1 × 2 × T) × (2 × L / 3)) Equation 1; Where A1 is the equivalent heat dissipation area of ​​the axial airflow between magnetic poles, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, n1 is the number of heat dissipation turns, T is the length of the heat dissipation turn extending beyond the non-heat dissipation turn in the width direction, and L is the axial length of the coil.

[0011] The equivalent heat dissipation area of ​​the radial air duct between the magnetic poles is calculated using Equation 2; A2 = N × (2 × (n × H + n1 × 2 × T) × L / 3) Equation 2; Where A2 is the equivalent heat dissipation area of ​​the radial airflow channel between magnetic poles, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, n1 is the number of heat dissipation turns, T is the length of the heat dissipation turn extending beyond the non-heat dissipation turn in the width direction, and L is the axial length of the coil.

[0012] The equivalent heat dissipation area of ​​the cold air duct inside the magnetic pole coil is calculated using Equation 3. A3 = N × (2 × (n × H) × (2 × L / 3) - M × S3 + M × (2 × (a + b) × c)) Equation 3; Where A3 is the equivalent heat dissipation area of ​​the cooling air duct inside the magnetic pole coil, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, L is the axial length of the coil, M is the number of cooling ventilation holes inside a single magnetic pole coil, S3 is the ventilation cross-sectional area of ​​a single cooling ventilation hole, a is the height of the cooling ventilation hole, b is the width of the cooling ventilation hole, and c is the width of the non-heat dissipation copper busbar.

[0013] In step 2, the total ventilation volume is calculated using formula 4; Q = Q0 × P / P0 (Equation 4); Where Q is the total ventilation volume, Q0 is the measured total ventilation volume of the unit with the same ventilation structure in the past, P is the total loss, and P0 is the measured total loss carried away by the cooling air of the unit with the same ventilation structure in the past.

[0014] In step 2, determining whether to adjust the duct structure size means that if the total ventilation volume and the total stator loss satisfy Equation 5, and the wind speed in each duct is not greater than 40m / s, then the duct structure size is not adjusted; otherwise, the duct structure size is adjusted, and step 2 is repeated for iterative calculation until the condition of not adjusting the duct structure size is met. Pc≤Q / Q0×Pc0 (Equation 5); Where Pc is the total stator loss, Q is the total ventilation volume, Q0 is the measured total air volume of the unit with the same ventilation structure in the past, and Pc0 is the measured stator loss carried away by the cooling air of the unit with the same ventilation structure in the past.

[0015] In step 3, the equivalent wind speed of the air duct includes the equivalent wind speed of the axial air duct between magnetic poles, the equivalent wind speed of the radial air duct between magnetic poles, and the equivalent wind speed of the cooling air duct inside the magnetic pole coil.

[0016] The equivalent wind speed of the axial air duct between the magnetic poles is calculated using Equation 6. V1=Q1 / (N×2×S1) Equation 6; Where V1 is the equivalent wind speed of the axial air duct between magnetic poles, Q1 is the ventilation volume of the axial air duct between magnetic poles, N is the number of magnetic poles, and S1 is the horizontal cross-sectional area of ​​the axial air duct formed by the outer surface of adjacent magnetic poles and the inner surface of the stator.

[0017] The equivalent wind speed of the radial air duct between the magnetic poles is calculated using Equation 7. V2=Q2 / (N×S2) Equation 7; Where V2 is the equivalent wind speed of the radial air duct between magnetic poles, Q2 is the ventilation air volume of the radial air duct between magnetic poles, N is the number of magnetic poles, and S2 is the axial cross-sectional area at the radial midpoint of the radial air duct formed on the outer surface of the middle part of the adjacent magnetic pole coils. The equivalent wind speed of the cooling duct inside the magnetic pole coil is calculated using Equation 8. V3=Q3 / (N×M×S3) Equation 8; Where V3 is the equivalent wind speed of the cooling air duct inside the magnetic pole coil, Q3 is the ventilation air volume of the cooling air duct inside the magnetic pole coil, N is the number of magnetic poles, M is the number of cooling ventilation holes inside a single magnetic pole coil, and S3 is the ventilation cross-sectional area of ​​a single cooling ventilation hole.

[0018] In step 4, the heat dissipation conditions are calculated using Equation 9; Equation 9; in, For heat dissipation conditions, This represents the airflow percentage for each air duct. For the wind speed in each air duct, This represents the equivalent heat dissipation area of ​​each air duct. Q represents the ventilation volume of each air duct, and Q represents the total ventilation volume.

[0019] In step 4, the temperature rise comparison coefficient is calculated using Equation 10; Formula 10; in, This is the temperature rise comparison coefficient. Total loss, For heat dissipation conditions.

[0020] In step 5, iterative optimization to complete the selection means that if the measured temperature rise in the historical unit is lower than the calculated temperature rise, then the iteration ends when Equation 11 is satisfied; if the measured temperature rise in the historical unit is higher than the calculated temperature rise, then the iteration ends when Equation 12 is satisfied. Formula 11; Equation 12; in, Let be the temperature rise comparison coefficient of the j-th iteration scheme. This is the temperature rise comparison coefficient for the unit whose measured temperature rise is closest to the calculated temperature rise among historical units. This is the ratio of the measured temperature rise to the calculated temperature rise.

[0021] The beneficial effects of this invention are mainly reflected in the following aspects: 1. Compared with the prior art, the present invention can quickly complete the cooling calculation of the rotor cooling structure in the preliminary selection stage, shorten the rotor selection and design cycle, and improve the selection accuracy and reliability.

[0022] 2. Compared with the traditional selection and design process, this invention can significantly reduce the number of iterations for detailed calculations, thereby improving design efficiency.

[0023] 3. This invention adopts a method based on historical unit data and iterative scheme comparison, which not only has high accuracy, but also can continuously enrich the comparison database as new units are put into operation and the selection and design work progresses, thereby continuously improving the selection accuracy of the calculation method.

[0024] 4. The present invention has a simple and efficient calculation method, which can greatly improve the efficiency of rotor selection.

[0025] 5. This invention can lay the foundation for the engineering application and promotion of rotor partitioned air cooling technology, and also provides a reference for the selection and calculation of other complex cooling methods, and has high efficiency.

[0026] 6. This invention significantly improves heat dissipation efficiency and temperature rise control accuracy by accurately calculating the equivalent heat dissipation area and wind speed of the rotor air duct and optimizing the ventilation structure design.

[0027] 7. This invention, based on historical data comparison and iteration, can quickly complete the rotor cooling selection, shorten the R&D cycle and ensure the reliability of unit operation.

[0028] 8. This invention proposes heat dissipation condition parameters that comprehensively describe the heat dissipation capacity of each airflow path, and establishes a basis for preliminary selection and accurate comparison. Compared with traditional preliminary selection design, it has higher accuracy and iteration rate, and creates an implementation path for significantly reducing complex simulation selection calculations.

[0029] 9. The temperature rise comparison coefficient proposed in this invention organically combines the two core variables in the cooling problem of loss and heat dissipation capacity, and establishes a quantifiable parameter that can be evaluated and compared in the preliminary design stage. That is, the smaller the temperature rise comparison coefficient, the better the cooling effect, which solves the problem of difficulty in rapid and accurate evaluation in the traditional selection process.

[0030] 10. This invention constructs a judgment system for temperature rise selection iteration calculation, which comprehensively considers the calculation results and actual measurement results of similar historical units. That is, when the actual temperature rise of similar historical units is lower than the calculated temperature rise, the iteration can be stopped as long as the temperature rise comparison coefficient of the current selection iteration is equal to or slightly lower than the temperature rise comparison coefficient of similar historical units. When the actual temperature rise of similar historical units is higher than the calculated temperature rise, the iteration can be stopped only when the temperature rise comparison coefficient of the current selection iteration is lower than the temperature rise comparison coefficient of similar historical units to a certain extent. This extent is described by the ratio of the actual temperature rise to the calculated temperature rise of similar historical units. The greater the difference between the actual temperature rise and the calculated temperature rise, the larger this ratio is, and the lower the temperature rise comparison coefficient of the selection calculation needs to be iterated to. The entire judgment system has good robustness and self-optimization, and can continuously optimize the judgment value as the historical database grows to ensure the judgment effect. Attached Figure Description

[0031] The present invention will now be further described in detail with reference to the accompanying drawings and specific embodiments: Figure 1 This is a flowchart of the present invention; Figure 2 This is a schematic diagram of the air duct of the present invention; Figure 3 for Figure 2 AA view; Figure 4 for Figure 2 BB view; Figure 5 for Figure 2 CC view; The markings in the diagram are: 1. Axial air duct between magnetic poles, 2. Radial air duct between magnetic poles, 3. Cold air duct inside the magnetic pole coil. Detailed Implementation

[0032] Example 1 See Figure 1 A rapid selection and calculation method for the rotor partition air cooling of a pumped storage generator includes the following steps: Step 1: Calculate the equivalent heat dissipation area of ​​the air duct; Step 2: Calculate the total ventilation volume and the air volume of each duct, and determine whether to adjust the duct structure dimensions; Step 3: Calculate the equivalent wind speed in the duct; Step 4: Calculate the heat dissipation conditions and temperature rise comparison coefficient; Step 5: By comparing the calculated temperature rise with the measured temperature rise in historical units, iterative optimization is performed to complete the selection.

[0033] This embodiment is the most basic implementation method. Compared with the prior art, it can quickly complete the cooling calculation of the rotor cooling structure in the preliminary selection stage, shorten the rotor selection and design cycle, and improve the selection accuracy and reliability.

[0034] Example 2 See Figures 1-5 A rapid selection and calculation method for the rotor partition air cooling of a pumped storage generator includes the following steps: Step 1: Calculate the equivalent heat dissipation area of ​​the air duct; Step 2: Calculate the total ventilation volume and the air volume of each duct, and determine whether to adjust the duct structure dimensions; Step 3: Calculate the equivalent wind speed in the duct; Step 4: Calculate the heat dissipation conditions and temperature rise comparison coefficient; Step 5: By comparing the calculated temperature rise with the measured temperature rise in historical units, iterative optimization is performed to complete the selection.

[0035] Preferably, in step 1, the air duct includes an axial air duct 1 between magnetic poles, a radial air duct 2 between magnetic poles, and a cooling air duct 3 inside the magnetic pole coil.

[0036] The equivalent heat dissipation area of ​​the axial air duct 1 between magnetic poles is calculated using Equation 1. A1 = N × (2 × (n × H + n1 × 2 × T) × (2 × L / 3)) Equation 1; Where A1 is the equivalent heat dissipation area of ​​the axial air duct 1 between magnetic poles, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, n1 is the number of heat dissipation turns, T is the length of the heat dissipation turn extending beyond the non-heat dissipation turn in the width direction, and L is the axial length of the coil.

[0037] The equivalent heat dissipation area of ​​the radial air duct 2 between the magnetic poles is calculated using Equation 2; A2 = N × (2 × (n × H + n1 × 2 × T) × L / 3) Equation 2; Where A2 is the equivalent heat dissipation area of ​​the radial air duct 2 between magnetic poles, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, n1 is the number of heat dissipation turns, T is the length of the heat dissipation turn extending beyond the non-heat dissipation turn in the width direction, and L is the axial length of the coil.

[0038] The equivalent heat dissipation area of ​​the cold air duct 3 inside the magnetic pole coil is calculated using Equation 3. A3 = N × (2 × (n × H) × (2 × L / 3) - M × S3 + M × (2 × (a + b) × c)) Equation 3; Where A3 is the equivalent heat dissipation area of ​​the cooling air duct 3 inside the magnetic pole coil, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, L is the axial length of the coil, M is the number of cooling ventilation holes inside a single magnetic pole coil, S3 is the ventilation cross-sectional area of ​​a single cooling ventilation hole, a is the height of the cooling ventilation hole, b is the width of the cooling ventilation hole, and c is the width of the non-heat dissipation copper busbar.

[0039] This embodiment is a preferred implementation method. Compared with the traditional selection and design process, it can significantly reduce the number of iterations for detailed calculations, thereby improving design efficiency.

[0040] Example 3 See Figures 1-5 A rapid selection and calculation method for the rotor partition air cooling of a pumped storage generator includes the following steps: Step 1: Calculate the equivalent heat dissipation area of ​​the air duct; Step 2: Calculate the total ventilation volume and the air volume of each duct, and determine whether to adjust the duct structure dimensions; Step 3: Calculate the equivalent wind speed in the duct; Step 4: Calculate the heat dissipation conditions and temperature rise comparison coefficient; Step 5: By comparing the calculated temperature rise with the measured temperature rise in historical units, iterative optimization is performed to complete the selection.

[0041] In step 1, the air duct includes an axial air duct 1 between magnetic poles, a radial air duct 2 between magnetic poles, and a cooling air duct 3 inside the magnetic pole coil.

[0042] The equivalent heat dissipation area of ​​the axial air duct 1 between magnetic poles is calculated using Equation 1. A1 = N × (2 × (n × H + n1 × 2 × T) × (2 × L / 3)) Equation 1; Where A1 is the equivalent heat dissipation area of ​​the axial air duct 1 between magnetic poles, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, n1 is the number of heat dissipation turns, T is the length of the heat dissipation turn extending beyond the non-heat dissipation turn in the width direction, and L is the axial length of the coil.

[0043] The equivalent heat dissipation area of ​​the radial air duct 2 between the magnetic poles is calculated using Equation 2; A2 = N × (2 × (n × H + n1 × 2 × T) × L / 3) Equation 2; Where A2 is the equivalent heat dissipation area of ​​the radial air duct 2 between magnetic poles, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, n1 is the number of heat dissipation turns, T is the length of the heat dissipation turn extending beyond the non-heat dissipation turn in the width direction, and L is the axial length of the coil.

[0044] The equivalent heat dissipation area of ​​the cold air duct 3 inside the magnetic pole coil is calculated using Equation 3. A3 = N × (2 × (n × H) × (2 × L / 3) - M × S3 + M × (2 × (a + b) × c)) Equation 3; Where A3 is the equivalent heat dissipation area of ​​the cooling air duct 3 inside the magnetic pole coil, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, L is the axial length of the coil, M is the number of cooling ventilation holes inside a single magnetic pole coil, S3 is the ventilation cross-sectional area of ​​a single cooling ventilation hole, a is the height of the cooling ventilation hole, b is the width of the cooling ventilation hole, and c is the width of the non-heat dissipation copper busbar.

[0045] In step 2, the total ventilation volume is calculated using formula 4; Q = Q0 × P / P0 (Equation 4); Where Q is the total ventilation volume, Q0 is the measured total ventilation volume of the unit with the same ventilation structure in the past, P is the total loss, and P0 is the measured total loss carried away by the cooling air of the unit with the same ventilation structure in the past.

[0046] In step 2, determining whether to adjust the duct structure size means that if the total ventilation volume and the total stator loss satisfy Equation 5, and the wind speed in each duct is not greater than 40m / s, then the duct structure size is not adjusted; otherwise, the duct structure size is adjusted, and step 2 is repeated for iterative calculation until the condition of not adjusting the duct structure size is met. Pc≤Q / Q0×Pc0 (Equation 5); Where Pc is the total stator loss, Q is the total ventilation volume, Q0 is the measured total air volume of the unit with the same ventilation structure in the past, and Pc0 is the measured stator loss carried away by the cooling air of the unit with the same ventilation structure in the past.

[0047] This embodiment is another preferred implementation method, which adopts a method based on historical unit data and iterative scheme comparison. It not only has high accuracy, but also can continuously enrich the comparison database as new units are put into operation and the selection and design work progresses, thereby continuously improving the selection accuracy of the calculation method.

[0048] The entire calculation method is simple and efficient, which can greatly improve the efficiency of rotor selection. It can lay the foundation for the engineering application and promotion of rotor partitioned air cooling technology, and also provide a reference for the selection calculation of other complex cooling methods, demonstrating high efficiency.

[0049] By accurately calculating the equivalent heat dissipation area and wind speed of the rotor air duct, and optimizing the ventilation structure design, the heat dissipation efficiency and temperature rise control accuracy are significantly improved.

[0050] Based on historical data comparison and iteration, rotor cooling selection can be completed quickly, shortening the R&D cycle and ensuring the reliability of unit operation.

[0051] Example 4 See Figures 1-5A rapid selection and calculation method for the rotor partition air cooling of a pumped storage generator includes the following steps: Step 1: Calculate the equivalent heat dissipation area of ​​the air duct; Step 2: Calculate the total ventilation volume and the air volume of each duct, and determine whether to adjust the duct structure dimensions; Step 3: Calculate the equivalent wind speed in the duct; Step 4: Calculate the heat dissipation conditions and temperature rise comparison coefficient; Step 5: By comparing the calculated temperature rise with the measured temperature rise in historical units, iterative optimization is performed to complete the selection.

[0052] In step 1, the air duct includes an axial air duct 1 between magnetic poles, a radial air duct 2 between magnetic poles, and a cooling air duct 3 inside the magnetic pole coil.

[0053] The equivalent heat dissipation area of ​​the axial air duct 1 between magnetic poles is calculated using Equation 1. A1 = N × (2 × (n × H + n1 × 2 × T) × (2 × L / 3)) Equation 1; Where A1 is the equivalent heat dissipation area of ​​the axial air duct 1 between magnetic poles, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, n1 is the number of heat dissipation turns, T is the length of the heat dissipation turn extending beyond the non-heat dissipation turn in the width direction, and L is the axial length of the coil.

[0054] The equivalent heat dissipation area of ​​the radial air duct 2 between the magnetic poles is calculated using Equation 2; A2 = N × (2 × (n × H + n1 × 2 × T) × L / 3) Equation 2; Where A2 is the equivalent heat dissipation area of ​​the radial air duct 2 between magnetic poles, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, n1 is the number of heat dissipation turns, T is the length of the heat dissipation turn extending beyond the non-heat dissipation turn in the width direction, and L is the axial length of the coil.

[0055] The equivalent heat dissipation area of ​​the cold air duct 3 inside the magnetic pole coil is calculated using Equation 3. A3 = N × (2 × (n × H) × (2 × L / 3) - M × S3 + M × (2 × (a + b) × c)) Equation 3; Where A3 is the equivalent heat dissipation area of ​​the cooling air duct 3 inside the magnetic pole coil, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, L is the axial length of the coil, M is the number of cooling ventilation holes inside a single magnetic pole coil, S3 is the ventilation cross-sectional area of ​​a single cooling ventilation hole, a is the height of the cooling ventilation hole, b is the width of the cooling ventilation hole, and c is the width of the non-heat dissipation copper busbar.

[0056] In step 2, the total ventilation volume is calculated using formula 4; Q = Q0 × P / P0 (Equation 4); Where Q is the total ventilation volume, Q0 is the measured total ventilation volume of the unit with the same ventilation structure in the past, P is the total loss, and P0 is the measured total loss carried away by the cooling air of the unit with the same ventilation structure in the past.

[0057] More preferably, in step 2, determining whether to adjust the duct structure size means that if the total ventilation volume and the total stator loss satisfy Equation 5, and the wind speed in each duct is not greater than 40m / s, then the duct structure size is not adjusted; otherwise, the duct structure size is adjusted, and step 2 is repeated iteratively until the condition of not adjusting the duct structure size is met. Pc≤Q / Q0×Pc0 (Equation 5); Where Pc is the total stator loss, Q is the total ventilation volume, Q0 is the measured total air volume of the unit with the same ventilation structure in the past, and Pc0 is the measured stator loss carried away by the cooling air of the unit with the same ventilation structure in the past.

[0058] In step 3, the equivalent wind speed of the air duct includes the equivalent wind speed of the axial air duct 1 between magnetic poles, the equivalent wind speed of the radial air duct 2 between magnetic poles, and the equivalent wind speed of the cooling air duct 3 inside the magnetic pole coil.

[0059] The equivalent wind speed of the axial air duct 1 between magnetic poles is calculated using Equation 6. V1=Q1 / (N×2×S1) Equation 6; Wherein, V1 is the equivalent wind speed of the axial air duct 1 between magnetic poles, Q1 is the ventilation air volume of the axial air duct 1 between magnetic poles, N is the number of magnetic poles, and S1 is the horizontal cross-sectional area of ​​the axial air duct formed by the outer surface of the adjacent magnetic poles and the inner surface of the stator.

[0060] The equivalent wind speed of the radial air duct 2 between the magnetic poles is calculated using Equation 7; V2=Q2 / (N×S2) Equation 7; Where V2 is the equivalent wind speed of the radial air duct 2 between magnetic poles, Q2 is the ventilation air volume of the radial air duct 2 between magnetic poles, N is the number of magnetic poles, and S2 is the axial cross-sectional area at the radial middle position of the radial air duct formed on the outer surface of the middle part of the adjacent magnetic pole coils. The equivalent wind speed of the cooling air duct 3 inside the magnetic pole coil is calculated using Equation 8. V3=Q3 / (N×M×S3) Equation 8; Wherein, V3 is the equivalent wind speed of the cooling air duct 3 inside the magnetic pole coil, Q3 is the ventilation air volume of the cooling air duct 3 inside the magnetic pole coil, N is the number of magnetic poles, M is the number of cooling ventilation holes inside a single magnetic pole coil, and S3 is the ventilation cross-sectional area of ​​a single cooling ventilation hole.

[0061] In step 4, the heat dissipation conditions are calculated using Equation 9; Equation 9; in, For heat dissipation conditions, This represents the airflow percentage for each air duct. For the wind speed in each air duct, This represents the equivalent heat dissipation area of ​​each air duct. Q represents the ventilation volume of each air duct, and Q represents the total ventilation volume.

[0062] In step 4, the temperature rise comparison coefficient is calculated using Equation 10; Formula 10; in, This is the temperature rise comparison coefficient. Total loss, For heat dissipation conditions.

[0063] In step 5, iterative optimization to complete the selection means that if the measured temperature rise in the historical unit is lower than the calculated temperature rise, then the iteration ends when Equation 11 is satisfied; if the measured temperature rise in the historical unit is higher than the calculated temperature rise, then the iteration ends when Equation 12 is satisfied. Formula 11; Equation 12; in, Let be the temperature rise comparison coefficient of the j-th iteration scheme. This is the temperature rise comparison coefficient for the unit whose measured temperature rise is closest to the calculated temperature rise among historical units. This is the ratio of the measured temperature rise to the calculated temperature rise.

[0064] This embodiment represents the optimal implementation method. It proposes heat dissipation condition parameters that comprehensively describe the heat dissipation capacity of each airflow path, and establishes a basis for preliminary selection and accurate comparison. Compared with traditional preliminary selection design, it has higher accuracy and iteration rate, creating an implementation path for significantly reducing complex simulation selection calculations.

[0065] The proposed temperature rise comparison coefficient organically combines the two core variables in the cooling problem of heat loss and heat dissipation capacity, and establishes a quantifiable parameter that can be evaluated and compared in the preliminary design stage. That is, the smaller the temperature rise comparison coefficient, the better the cooling effect, which solves the problem of difficulty in rapid and accurate evaluation in the traditional selection process.

[0066] The basic principle of this invention is as follows: Parametric design of the partitioned internal cooling structure of the pumped storage generator rotor is carried out through coupled thermodynamic and fluid dynamic calculations. First, the equivalent heat dissipation area is calculated based on the geometric characteristics of the air duct, and the total air volume and the air volume distribution of each branch are solved by combining ventilation network theory. Then, the equivalent wind speed reflecting the flow capacity of the cooling medium is derived, thereby establishing a mathematical correlation model between heat dissipation capacity and temperature rise.

[0067] After calculating the initial design parameters, a comparative analysis is performed, comparing the calculated temperature rise coefficient with the measured temperature rise data of historical units. By identifying the deviation between theoretical calculations and actual operating data, the dimensions of the air duct structure are adjusted in reverse and iteratively optimized until the preset heat dissipation performance indicators are met, thereby achieving rapid and accurate rotor cooling selection.

[0068] A judgment system for temperature rise selection iteration calculation is constructed, comprehensively considering the calculation results and actual measurement results of similar historical units. Specifically, when the actual temperature rise of similar historical units is lower than the calculated temperature rise, the iteration can be stopped as long as the temperature rise comparison coefficient of the current selection iteration is equal to or slightly lower than the temperature rise comparison coefficient of similar historical units. When the actual temperature rise of similar historical units is higher than the calculated temperature rise, the iteration can be stopped only when the temperature rise comparison coefficient of the current selection iteration is lower than the temperature rise comparison coefficient of similar historical units to a certain extent. This extent is described by the ratio of the actual temperature rise to the calculated temperature rise of similar historical units. The greater the difference between the actual temperature rise and the calculated temperature rise, the larger this ratio, and the lower the temperature rise comparison coefficient of the selection calculation needs to be iterated to. The entire judgment system has good robustness and self-optimization, and can continuously optimize the judgment value as the historical database grows, ensuring the judgment effect.

Claims

1. A rapid selection and calculation method for the rotor partitioning and internal cooling of a pumped storage generator, characterized in that, Includes the following steps: Step 1: Calculate the equivalent heat dissipation area of ​​the air duct; Step 2: Calculate the total ventilation volume and the air volume of each duct, and determine whether to adjust the duct structure dimensions; Step 3: Calculate the equivalent wind speed in the duct; Step 4: Calculate the heat dissipation conditions and temperature rise comparison coefficient; Step 5: By comparing the calculated temperature rise with the measured temperature rise in historical units, iterative optimization is performed to complete the selection; In step 4, the heat dissipation conditions are calculated using Equation 9; Equation 9; in, For heat dissipation conditions, This represents the airflow percentage for each air duct. For the wind speed in each air duct, This represents the equivalent heat dissipation area of ​​each air duct. Q represents the ventilation volume of each air duct, and Q represents the total ventilation volume. In step 4, the temperature rise comparison coefficient is calculated using Equation 10; Formula 10; in, This is the temperature rise comparison coefficient. Total loss, For heat dissipation conditions; In step 5, iterative optimization to complete the selection means that if the measured temperature rise in the historical unit is lower than the calculated temperature rise, then the iteration ends when Equation 11 is satisfied; if the measured temperature rise in the historical unit is higher than the calculated temperature rise, then the iteration ends when Equation 12 is satisfied. Formula 11; Equation 12; in, Let be the temperature rise comparison coefficient of the j-th iteration scheme. This is the temperature rise comparison coefficient for the unit whose measured temperature rise is closest to the calculated temperature rise among historical units. This is the ratio of the measured temperature rise to the calculated temperature rise.

2. The method for rapid selection and calculation of rotor partitioning and internal cooling for pumped storage generators according to claim 1, characterized in that: In step 1, the air duct includes an axial air duct between magnetic poles (1), a radial air duct between magnetic poles (2), and a cold air duct inside the magnetic pole coil (3).

3. The method for rapid selection and calculation of rotor partitioning and internal cooling for pumped storage generators according to claim 2, characterized in that: The equivalent heat dissipation area of ​​the axial air duct (1) between magnetic poles is calculated by Equation 1; A1 = N × (2 × (n × H + n1 × 2 × T) × (2 × L / 3)) Equation 1; Where A1 is the equivalent heat dissipation area of ​​the axial air duct (1) between magnetic poles, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil, n1 is the number of heat dissipation turns, T is the length of the heat dissipation turn extending beyond the non-heat dissipation turn in the width direction, and L is the axial length of the coil.

4. The method for rapid selection and calculation of rotor partitioning and internal cooling for pumped storage generators according to claim 2, characterized in that: The equivalent heat dissipation area of ​​the radial air duct between the magnetic poles (2) is calculated by Equation 2; A2 = N × (2 × (n × H + n1 × 2 × T) × L / 3) Equation 2; Where A2 is the equivalent heat dissipation area of ​​the radial air duct (2) between magnetic poles, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil, n1 is the number of heat dissipation turns, T is the length of the heat dissipation turn extending beyond the non-heat dissipation turn in the width direction, and L is the axial length of the coil.

5. The method for rapid selection and calculation of rotor partitioned internal cooling for pumped storage generators according to claim 2, characterized in that: The equivalent heat dissipation area of ​​the cold air duct (3) inside the magnetic pole coil is calculated by Equation 3; A3 = N × (2 × (n × H) × (2 × L / 3) - M × S3 + M × (2 × (a + b) × c)) Equation 3; Where A3 is the equivalent heat dissipation area of ​​the cooling air duct (3) inside the magnetic pole coil, N is the number of magnetic poles, n is the total number of coil turns, H is the thickness of the copper busbar of a single coil turn, L is the axial length of the coil, M is the number of cooling ventilation holes inside a single magnetic pole coil, S3 is the ventilation cross-sectional area of ​​a single cooling ventilation hole, a is the height of the cooling ventilation hole, b is the width of the cooling ventilation hole, and c is the width of the non-heat dissipation copper busbar.

6. The method for rapid selection and calculation of rotor partitioning and internal cooling for pumped storage generators according to claim 1, characterized in that: In step 2, the total ventilation volume is calculated using formula 4; Q = Q0 × P / P0 (Equation 4); Where Q is the total ventilation volume, Q0 is the measured total ventilation volume of the unit with the same ventilation structure in the past, P is the total loss, and P0 is the measured total loss carried away by the cooling air of the unit with the same ventilation structure in the past.

7. The method for rapid selection and calculation of rotor partitioned internal cooling for pumped storage generators according to claim 6, characterized in that: In step 2, determining whether to adjust the duct structure size means that if the total ventilation volume and the total stator loss satisfy Equation 5, and the wind speed in each duct is not greater than 40m / s, then the duct structure size is not adjusted; otherwise, the duct structure size is adjusted, and step 2 is repeated for iterative calculation until the condition of not adjusting the duct structure size is met. Pc≤Q / Q0×Pc0 Equation 5; Where Pc is the total stator loss, Q is the total ventilation volume, Q0 is the measured total air volume of the unit with the same ventilation structure in the past, and Pc0 is the measured stator loss carried away by the cooling air of the unit with the same ventilation structure in the past.

8. The method for rapid selection and calculation of rotor partitioning and internal cooling of a pumped storage generator according to claim 1, characterized in that: In step 3, the equivalent wind speed of the air duct includes the equivalent wind speed of the axial air duct (1) between magnetic poles, the equivalent wind speed of the radial air duct (2) between magnetic poles, and the equivalent wind speed of the cooling air duct (3) inside the magnetic pole coil.

9. The method for rapid selection and calculation of rotor partitioned internal cooling for pumped storage generators according to claim 8, characterized in that: The equivalent wind speed of the axial air duct (1) between the magnetic poles is calculated using Equation 6; V1 = Q1 / (N × 2 × S1) Equation 6; Wherein, V1 is the equivalent wind speed of the axial air duct (1) between magnetic poles, Q1 is the ventilation air volume of the axial air duct (1) between magnetic poles, N is the number of magnetic poles, and S1 is the horizontal cross-sectional area of ​​the axial air duct formed by the outer surface of the adjacent magnetic poles and the inner surface of the stator.

10. The method for rapid selection and calculation of rotor partitioning and internal cooling for pumped storage generators according to claim 8, characterized in that: The equivalent wind speed of the radial air duct (2) between the magnetic poles is calculated using Equation 7; V2 = Q2 / (N×S2) Equation 7; Wherein, V2 is the equivalent wind speed of the radial air duct (2) between magnetic poles, Q2 is the ventilation air volume of the radial air duct (2) between magnetic poles, N is the number of magnetic poles, and S2 is the axial cross-sectional area at the radial middle position of the radial air duct formed on the outer surface of the middle part of the adjacent magnetic pole coils.

11. The method for rapid selection and calculation of rotor partitioning and internal cooling for pumped storage generators according to claim 8, characterized in that: The equivalent wind speed of the cold air duct (3) inside the magnetic pole coil is calculated using Equation 8; V3=Q3 / (N×M×S3) Equation 8; Wherein, V3 is the equivalent wind speed of the cooling air duct (3) inside the magnetic pole coil, Q3 is the ventilation air volume of the cooling air duct (3) inside the magnetic pole coil, N is the number of magnetic poles, M is the number of cooling ventilation holes inside a single magnetic pole coil, and S3 is the ventilation cross-sectional area of ​​a single cooling ventilation hole.

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