Grading ring optimization design method and system
By attaching strain gauges to the pressure-equalizing ring, establishing a dynamic stress prediction model, and optimizing the supporting ribs and ring structure, the stress concentration problem under high wind speeds was solved, the stress distribution was optimized, the service life of the pressure-equalizing ring was extended, and the maintenance cost was reduced.
Patent Information
- Application Number
- CN202510822192.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-19
- Publication Date
- 2025-09-19
AI Technical Summary
The existing pressure equalizing ring design is prone to local stress concentration, fatigue damage and fracture under high wind speed conditions. The lack of accurate modeling of the dynamic impact of wind speed leads to design redundancy or insufficient strength.
By attaching strain gauges on the support ribs and the ring body, a dynamic stress prediction model is established. The least squares method is used to fit the fourth-order polynomial equation to optimize the cross-sectional shape of the support ribs, the thickness of the ring body, and the spacing between the support ribs. Combined with finite element software verification, the shape is adjusted to a gradual conical shape and non-uniform thickness to achieve active optimization of the stress distribution.
Significantly reduce maximum stress, extend fatigue life, reduce maintenance costs, and make stress distribution more reasonable.
Smart Images
Figure CN120671468A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to a pressure equalizing ring manufacturing technology and relates to an optimized design of a pressure equalizing ring. Background Art
[0002] Insulators are used for supporting and insulating transmission lines. Due to their unique shape and structure, stray capacitance between insulator strings and metal components such as transmission line towers and conductors leads to uneven voltage distribution across insulator strings. As voltage levels rise, the number of insulators in a string increases, exacerbating the uneven voltage distribution and severely distorting the electric field. This causes the insulators at the conductor ends to bear higher voltages, leading to breakdown, discharge, degradation, and accelerated aging. Installing grading rings on insulator strings addresses these issues.
[0003] The equalizing ring is exposed to complex wind loads for extended periods. Traditionally, stress analysis of the support ribs and rings relies on empirical formulas or static load assumptions, which can lead to localized stress concentrations under high wind speeds, causing fatigue damage and even fracture. Existing technologies lack precise modeling of the dynamic effects of wind speed, making it impossible to accurately quantify the nonlinear relationship between wind speed and stress. This makes it difficult to proactively optimize stress distribution, leading to design redundancy or insufficient strength. Summary of the Invention
[0004] The purpose of the present invention is to propose an optimization design method for a pressure equalizing ring based on a wind speed-stress model, and at the same time propose a system suitable for this method.
[0005] The technical solution of the present invention is a method for optimizing the design of a pressure equalizing ring, comprising: A prototype pressure-equalizing ring with uniform cross-sectional support ribs was taken. Strain gauges were attached to the support ribs and the ring body, and the ring was placed in a wind tunnel. Stepwise wind forces were applied, and stress data of the support ribs and the ring body were collected through the strain gauges. The obtained support rib and ring stress data were fitted with a fourth-order polynomial equation based on the least squares method to establish a dynamic stress prediction model: Among them, the maximum stress model of the supporting reinforcement is: y=(0.37565)+(-0.08603)*x+(0.0096)*x 2 +(-2.68016E-4)*x 3 +(1.32223E-6)*x 4 ; Ring maximum stress model: y=(-0.14581)+(0.10129)*x+(-0.0152)*x 2 +(0.00105)*x 3 +(-2.17616E-5)*x 4 ; x is the wind speed, in m / s, and y is the stress of the supporting rib or ring corresponding to a certain wind speed, in MPa; Based on the historical wind speed data of the target area, the critical stress values of the support ribs and the ring body are derived using a dynamic stress prediction model; Compare the allowable stress value of the material with the critical stress value of the material. If the allowable stress value of the material is greater than the critical stress value of the material, the structure of the equalizing ring is not optimized. If the allowable stress value of the material is less than the critical stress value of the material, the structure of the equalizing ring is optimized. The optimized structure includes the cross-sectional shape of the support ribs, the thickness of the ring body, and the spacing between the support ribs. Input the structurally optimized pressure equalizing ring parameters into the finite element software to generate a stress distribution cloud diagram to check whether the peak stress meets the requirements; A physical sample of the structurally optimized pressure-equalizing ring is produced for testing and compared with the stress distribution cloud map results of the finite element software. If the error is greater than the set range, the model parameters are readjusted and recalculated until the safety threshold is met.
[0006] According to the data parameters that meet the safety threshold, three-dimensional drawings are output for batch manufacturing of equalizing rings.
[0007] Furthermore, the structural optimization content of the pressure equalizing ring is as follows: the cross-sectional shape of the support ribs is adjusted to a non-uniform shape, the cross-sectional shape of the connection between the support ribs and the ring body is a gradual cone, the thickness of the ring body on the windward side is 8%-12% thicker than the thickness on the leeward side, and the spacing between the support ribs is reduced to 70%-80% of the original design of the pressure equalizing ring prototype.
[0008] Preferably, the wind speed range of the wind tunnel is 6-22 m / s.
[0009] Specifically, when testing physical samples, actual stress data is collected in a wind tunnel using strain gauges and high-speed cameras.
[0010] Preferably, the error range between the stress data obtained from the physical sample test and the stress distribution cloud map result of the finite element software is set to 5%. If it exceeds 5%, the model parameters are readjusted and recalculated.
[0011] A pressure equalizing ring optimization design system includes a support rib and ring body stress data acquisition unit, a data input unit, a data processing unit, and a model parameter readjustment unit; The supporting rib and ring body stress data acquisition unit is used to take a pressure-equalizing ring prototype with a uniform cross-sectional shape of the supporting rib, attach strain gauges to the supporting rib and the ring body, place it in a wind tunnel, apply step-by-step wind force, and collect the supporting rib and ring body stress data through the strain gauges; The data input unit is used to input the stress data of the support ribs and the ring body, and the historical wind speed data of the target area; The data processing unit executes the following program: The obtained support rib and ring stress data were fitted with a fourth-order polynomial equation based on the least squares method to establish a dynamic stress prediction model: Among them, the maximum stress model of the supporting reinforcement is: y=(0.37565)+(-0.08603)*x+(0.0096)*x 2 +(-2.68016E-4)*x 3 +(1.32223E-6)*x 4 ; Ring maximum stress model: y=(-0.14581)+(0.10129)*x+(-0.0152)*x 2 +(0.00105)*x 3 +(-2.17616E-5)*x 4 ; x is the wind speed, in m / s, and y is the stress of the supporting rib or ring corresponding to a certain wind speed, in MPa; Based on the historical wind speed data of the target area, the critical stress values of the support ribs and the ring body are derived using a dynamic stress prediction model; Compare the allowable stress value of the material with the critical stress value of the material. If the allowable stress value of the material is greater than the critical stress value of the material, the structure of the equalizing ring is not optimized. If the allowable stress value of the material is less than the critical stress value of the material, the structure of the equalizing ring is optimized. The optimized structure includes the cross-sectional shape of the support ribs, the thickness of the ring body, and the spacing between the support ribs. Import the structurally optimized pressure equalizing ring parameters into the finite element software to generate a stress distribution cloud diagram to check whether the peak stress meets the requirements; The model parameter readjustment unit executes the following procedure: the stress data obtained by testing a physical sample made according to the structurally optimized pressure-equalizing ring is compared with the stress distribution cloud map result of the finite element software. If the error is greater than the set range, the model parameters are readjusted and recalculated until the safety threshold is met.
[0012] Specifically, the structural optimization content of the pressure equalizing ring is as follows: the cross-sectional shape of the support ribs is adjusted to a non-uniform shape, the cross-sectional shape of the connection between the support ribs and the ring body is adjusted to a gradual cone shape, the thickness of the ring body on the windward side is 8%-12% thicker than the thickness on the leeward side, and the spacing between the support ribs is reduced to 70%-80% of the original design of the pressure equalizing ring prototype.
[0013] Preferably, the wind speed range of the wind tunnel in the support rib and ring body stress data acquisition unit is 6-22 m / s.
[0014] Specifically, when testing physical samples, actual stress data is collected in a wind tunnel using strain gauges and high-speed cameras.
[0015] The model parameter readjustment unit error setting range is 5%. If it exceeds 5%, the model parameters are readjusted and recalculated.
[0016] The present invention has the following beneficial effects: The nonlinear relationship between wind speed and stress in the pressure equalizing ring is determined, resulting in precisely matched structural parameters. Through simulation and wind tunnel simulation, a multi-physics collaborative verification mechanism is established. Under certain wind speed conditions, the pressure equalizing ring optimized using this method exhibits significantly reduced maximum stress, extended fatigue life, and reduced maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 is the relationship between wind speed and maximum stress of supporting reinforcement; Figure 2 is the relationship between wind speed and maximum stress in the ring; Figure 3 This is the shape and structure diagram of the existing pressure equalizing ring; Figure 4 It is a three-dimensional model diagram of the pressure equalizing ring; Figure 5 This is the maximum stress simulation of the optimized support reinforcement at a wind speed of 6m / s; Figure 6 This is the optimized ring maximum stress simulation at a wind speed of 6m / s; Figure 7 This is the maximum stress simulation of the optimized support reinforcement at a wind speed of 22m / s; Figure 8 This is the optimized ring maximum stress simulation at a wind speed of 22m / s. DETAILED DESCRIPTION
[0018] The embodiment of the present invention proposes a method for optimizing the design of a pressure equalizing ring based on a wind speed-stress model. The specific processing process is as follows: Take Figure 3 、 4 The prior art pressure-equalizing ring prototype shown (performance data shown in Table 1) features uniform cross-sectional shapes of its support ribs, with no thickness or shape variations. Strain gauges were attached to the support ribs and the ring body, and the ring was placed in a wind tunnel. Stepwise wind forces were applied from low to high within a wind speed range of 6-22 m / s. Stress data for the support ribs and the ring body were collected using the strain gauges, as shown in Table 2. Table 1 Performance parameters of existing equalizing ring materials Table 2 Wind tunnel stress data of support ribs and ring body The obtained support rib and ring stress data were fitted with a fourth-order polynomial equation based on the least squares method to establish a dynamic stress prediction model: Among them, the maximum stress model of the supporting reinforcement is: y=(0.37565)+(-0.08603)*x+(0.0096)*x 2 +(-2.68016E-4)*x 3 +(1.32223E-6)*x 4 ; Ring maximum stress model: y=(-0.14581)+(0.10129)*x+(-0.0152)*x 2 +(0.00105)*x 3 +(-2.17616E-5)*x 4 ; x is the wind speed, in m / s, and y is the stress of the supporting rib or ring corresponding to a certain wind speed, in MPa; The above model is verified to have a fitting accuracy by the coefficient of determination (R²) ≥ 0.98. Figure 1 、 2 Comparing the curve in the figure with the measured data, it can be seen that the measured data basically agrees with the curve's changing trend.
[0019] Based on the historical wind speed data of the target area (such as the maximum design wind speed of 22m / s), the critical stress values of the support reinforcement and the ring body are derived using the dynamic stress prediction model.
[0020] Compare the allowable stress value of the material (such as 345MPa for Q345 steel) with the critical stress value of the material. If the allowable stress value of the material is greater than the critical stress value of the material, the structure of the equalizing ring will not be optimized. If the allowable stress value of the material is less than the critical stress value of the material, the structure of the equalizing ring will be optimized, including adjustments to the cross-sectional shape of the support ribs, the thickness of the ring body, and the spacing between the support ribs.
[0021] Optimize support ribs: Use a tapered cross-section design (e.g., increase the cross-section by 10%-15% near the root of the ring) to reduce stress gradients at high wind speeds; for example, adjust the cross-section of the support ribs to a tapered conical shape (increase the root diameter by 12%). Ring optimization: According to the stress distribution cloud map (see attached Figure 5-8 ), adjust the ring body thickness to be non-uniformly distributed (such as the thickness on the windward side increases by 8%-12%); for example, the ring body thickness is 10mm on the windward side and 8mm on the leeward side.
[0022] Layout density adjustment: In areas with wind speeds ≥15m / s, the spacing between support ribs is reduced to 70%-80% of the original design of the pressure equalizing ring prototype; for example, the spacing between support ribs is reduced from 200mm to 150mm.
[0023] Input the optimized parameters of the equalizing ring into the finite element software (such as CFD simulation software) to generate the stress distribution cloud diagram (such as Figure 5-8 According to the wind speed in Table 2, a stress distribution cloud diagram was generated for each value condition. To save space, only the diagrams of 6m / s and 22m / s were selected. The value of the maximum stress point is marked in the diagram, and the stress in each area is represented by different colors to check whether the peak stress meets the material allowable value requirements.
[0024] A physical sample of the structurally optimized pressure-equalizing ring was made. A step-by-step wind force was applied in a wind tunnel at a wind speed range of 6-22 m / s, from low to high. The measured stress data was collected using strain gauges and a high-speed camera and compared with the stress distribution cloud map results of the finite element software. If the error is greater than 5%, the model parameters are readjusted and recalculated until the safety threshold is met.
[0025] Once the data parameters of the pressure equalizing ring that meet the safety threshold are obtained, a three-dimensional drawing can be output for batch manufacturing of the pressure equalizing ring.
[0026] After the optimization of the above embodiment, the implementation effect of the obtained pressure equalizing ring is: (1) Significant stress reduction: At a wind speed of 22 m / s, the maximum stress of the support ribs after optimization decreased from 0.5822 MPa to 0.4658 MPa (a decrease of 20%), and the maximum stress of the ring body decreased from 0.8591 MPa to 0.7045 MPa (a decrease of 18%). (2) Life improvement: Fatigue life is estimated to be extended by 30%-50%, reducing maintenance costs.
[0027] In order to realize the above method, a pressure equalizing ring optimization design system is proposed, which includes a support rib and ring stress data acquisition unit, a data input unit, a data processing unit, and a model parameter readjustment unit. The support rib and ring body stress data acquisition unit is used to take a pressure-equalizing ring prototype with a uniform cross-sectional shape of the support rib, attach strain gauges to the support rib and the ring body, place it in a wind tunnel, apply a step-by-step wind force within a wind speed range of 6-22m / s, and collect support rib and ring body stress data through the strain gauges; The data input unit is used to input the stress data of the support ribs and the ring body, and the historical wind speed data of the target area; The data processing unit executes the following program: The obtained support rib and ring stress data were fitted with a fourth-order polynomial equation based on the least squares method to establish a dynamic stress prediction model: Among them, the maximum stress model of the supporting reinforcement is: y=(0.37565)+(-0.08603)*x+(0.0096)*x 2 +(-2.68016E-4)*x 3 +(1.32223E-6)*x 4 Ring maximum stress model: y=(-0.14581)+(0.10129)*x+(-0.0152)*x 2 +(0.00105)*x 3 +(-2.17616E-5)*x 4 ; x is the wind speed, in m / s, and y is the stress of the supporting rib or ring corresponding to a certain wind speed, in MPa; According to the historical wind speed data of the target area, the critical stress values of the support ribs and the ring body are derived using the dynamic stress prediction model.
[0028] Compare the material's allowable stress value with its critical stress value. If the material's allowable stress value is greater than the critical stress value, no structural optimization is performed on the equalizing ring. If the material's allowable stress value is less than the critical stress value, the equalizing ring is optimized. The optimized structure includes the cross-sectional shape of the support ribs, the ring body thickness, and the spacing between the support ribs. This includes adjusting the cross-sectional shape of the support ribs to a non-uniform shape, adjusting the cross-sectional shape of the connection between the support ribs and the ring body to a tapered conical shape, increasing the ring body thickness on the windward side by 8%-12% compared to the leeward side, and reducing the spacing between the support ribs to 70%-80% of the original design of the equalizing ring prototype.
[0029] Import the structurally optimized pressure equalizing ring parameters into the finite element software to generate a stress distribution cloud diagram to check whether the peak stress meets the requirements.
[0030] The model parameter readjustment unit executes the following procedure: a physical sample is manufactured based on the structurally optimized equalizing ring and tested (the physical sample test is conducted in a wind tunnel, and the measured stress data is collected using strain gauges and a high-speed camera). The stress data obtained is compared with the stress distribution cloud map results of the finite element software. If the error is greater than 5%, the model parameters are readjusted and recalculated until the safety threshold is met.
Claims
1. A method for optimizing the design of a pressure equalizing ring, characterized in that: include: A prototype pressure-equalizing ring with uniform cross-sectional support ribs was taken. Strain gauges were attached to the support ribs and the ring body, and the ring was placed in a wind tunnel. Stepwise wind forces were applied, and stress data of the support ribs and the ring body were collected through the strain gauges. The obtained support rib and ring stress data were fitted with a fourth-order polynomial equation based on the least squares method to establish a dynamic stress prediction model: Among them, the maximum stress model of the supporting reinforcement is: y=(0.37565)+(-0.08603)*x+(0.0096)*x 2 +(-2.68016E-4)*x 3 +(1.32223E-6)*x 4 ; Ring maximum stress model: y=(-0.14581)+(0.10129)*x+(-0.0152)*x 2 +(0.00105)*x 3 +(-2.17616E-5)*x 4 ; x is the wind speed, in m / s, and y is the stress of the supporting rib or ring corresponding to a certain wind speed, in MPa; Based on the historical wind speed data of the target area, the critical stress values of the support ribs and the ring body are derived using a dynamic stress prediction model; Compare the allowable stress value of the material with the critical stress value of the material. If the allowable stress value of the material is greater than the critical stress value of the material, the structure of the equalizing ring is not optimized. If the allowable stress value of the material is less than the critical stress value of the material, the structure of the equalizing ring is optimized. The optimized structure includes the cross-sectional shape of the support ribs, the thickness of the ring body, and the spacing between the support ribs. Input the structurally optimized pressure equalizing ring parameters into the finite element software to generate a stress distribution cloud diagram to check whether the peak stress meets the requirements; A physical sample of the structurally optimized pressure-equalizing ring is produced for testing and compared with the stress distribution cloud map results of the finite element software. If the error is greater than the set range, the model parameters are readjusted and recalculated until the safety threshold is met.
2. The method for optimizing the design of a pressure equalizing ring according to claim 1, wherein: The structural optimization content of the pressure equalizing ring is as follows: the cross-sectional shape of the support ribs is adjusted to a non-uniform shape, the cross-sectional shape of the connection between the support ribs and the ring body is adjusted to a gradual conical shape, the thickness of the ring body on the windward side is 8%-12% thicker than the thickness on the leeward side, and the spacing between the support ribs is reduced to 70%-80% of the original design of the pressure equalizing ring prototype.
3. The method for optimizing the design of a pressure equalizing ring according to claim 1, wherein: The wind speed range of the wind tunnel is 6-22m / s.
4. The method for optimizing the design of a pressure equalizing ring according to claim 1, wherein: When testing physical samples, actual stress data is collected in the wind tunnel using strain gauges and high-speed cameras.
5. The method for optimizing the design of a pressure equalizing ring according to claim 1, wherein: The error range between the stress data obtained from the physical sample test and the stress distribution cloud map results of the finite element software is set to 5%. If it exceeds 5%, the model parameters will be readjusted and recalculated.
6. A pressure equalizing ring optimization design system, characterized by: Contains support rib and ring stress data acquisition unit, data input unit, data processing unit, and model parameter readjustment unit; The supporting rib and ring body stress data acquisition unit is used to take a pressure-equalizing ring prototype with a uniform cross-sectional shape of the supporting rib, attach strain gauges to the supporting rib and the ring body, place it in a wind tunnel, apply step-by-step wind force, and collect the supporting rib and ring body stress data through the strain gauges; The data input unit is used to input the stress data of the support ribs and the ring body, and the historical wind speed data of the target area; The data processing unit executes the following program: The obtained support rib and ring stress data were fitted with a fourth-order polynomial equation based on the least squares method to establish a dynamic stress prediction model: Among them, the maximum stress model of the supporting reinforcement is: y=(0.37565)+(-0.08603)*x+(0.0096)*x 2 +(-2.68016E-4)*x 3 +(1.32223E-6)*x 4 ; Ring maximum stress model: y=(-0.14581)+(0.10129)*x+(-0.0152)*x 2 +(0.00105)*x 3 +(-2.17616E-5)*x 4 ; x is the wind speed, in m / s, and y is the stress of the supporting rib or ring corresponding to a certain wind speed, in MPa; Based on the historical wind speed data of the target area, the critical stress values of the support ribs and the ring body are derived using a dynamic stress prediction model; Compare the allowable stress value of the material with the critical stress value of the material. If the allowable stress value of the material is greater than the critical stress value of the material, the structure of the equalizing ring is not optimized. If the allowable stress value of the material is less than the critical stress value of the material, the structure of the equalizing ring is optimized. The optimized structure includes the cross-sectional shape of the support ribs, the thickness of the ring body, and the spacing between the support ribs. Import the structurally optimized pressure equalizing ring parameters into the finite element software to generate a stress distribution cloud diagram to check whether the peak stress meets the requirements; The model parameter readjustment unit executes the following procedure: the stress data obtained by testing a physical sample made according to the structurally optimized pressure-equalizing ring is compared with the stress distribution cloud map result of the finite element software. If the error is greater than the set range, the model parameters are readjusted and recalculated until the safety threshold is met.
7. The pressure equalizing ring optimization design system according to claim 6, characterized in that: The structural optimization content of the pressure equalizing ring is as follows: the cross-sectional shape of the support ribs is adjusted to a non-uniform shape, the cross-sectional shape of the connection between the support ribs and the ring body is adjusted to a gradual conical shape, the thickness of the ring body on the windward side is 8%-12% thicker than the thickness on the leeward side, and the spacing between the support ribs is reduced to 70%-80% of the original design of the pressure equalizing ring prototype.
8. The pressure equalizing ring optimization design system according to claim 6, characterized in that: The wind speed range of the wind tunnel in the support rib and ring body stress data acquisition unit is 6-22m / s.
9. The pressure equalizing ring optimization design system according to claim 6, characterized in that: When testing physical samples, actual stress data is collected in the wind tunnel using strain gauges and high-speed cameras.
10. The pressure equalizing ring optimization design system according to claim 6, characterized in that: The model parameter readjustment unit error setting range is 5%. If it exceeds 5%, the model parameters are readjusted and recalculated.