Design, evaluation method and system of double-sided bolt nodes for smart grid

Abstract

The present invention provides a double-sided bolt node design, evaluation method and system for smart grid. It relates to the field of smart grid technology. The design method includes: obtaining the actual internal force borne by the double-sided bolt node under various operating conditions according to the load information of the transmission tower; determining the calculated thickness of the main stress node plate according to the maximum limb thickness of the limbs of several angle steel components connected to the main stress node plate; determining the calculated thickness of the secondary stress node plate according to the maximum limb thickness of the limbs of several angle steel components connected to the secondary stress node plate; calculating the theoretical connection stiffness of the main stress node plate and the secondary stress node plate according to the elastic modulus and calculated thickness of each stress node plate; and calculating the theoretical number of connecting bolts on each stress node plate when the double-sided bolt node can bear the most unfavorable internal force according to the obtained theoretical connection stiffness. The present invention can realize the digital design and bearing capacity evaluation of the double-sided bolt node of the transmission line.

Description

Technical Field

[0001] The present invention relates to the field of smart grid technology, and in particular to a double-sided bolt node design, evaluation method and system for smart grid. Background Art

[0002] With the rapid development of digital technology, digitalization and intelligence have gradually become the trends in various industries and an important way to improve quality and empower. In order to promote the development of smart grids and improve the efficiency and intelligence of transmission line design, it is urgent to realize the digitalization and dataization of grid design; double-sided bolt connection nodes are key nodes in the field of transmission line structure, and it is particularly important to digitally empower their design and evaluation.

[0003] Specifically, double-sided bolt connection nodes are usually used to improve the stiffness and bearing capacity of the connection to ensure the stability and safety of the transmission tower under various load conditions. The two connection surfaces form a whole to achieve a tight connection of the various components at the node position. However, research has found that the forces on the two connection surfaces in the double-sided bolt connection node are often not balanced, that is, the design method of the traditional single-sided bolt connection node is not suitable for the design or evaluation of the double-sided bolt connection node. At present, there is a lack of effective methods for the design or evaluation of double-sided bolt nodes, and it is difficult to make the bearing capacity of the double-sided bolt connection node meet the actual needs of the project through precise design.

[0004] In summary, there is an urgent need for a double-sided bolt node design and evaluation method that can be applied to smart grids, which can realize the digital design and bearing capacity evaluation of double-sided bolt connection nodes of transmission lines. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0006] To this end, the present invention provides a double-sided bolt node design method applied to a smart grid.

[0007] A second aspect of the present invention provides a double-sided bolt node evaluation method applied to a smart grid.

[0008] A third aspect of the present invention provides a double-sided bolt node design and evaluation system for use in a smart grid.

[0009] The present invention provides a double-sided bolt node design method for a smart grid, wherein the double-sided bolt node comprises at least a first stress-bearing node plate, a second stress-bearing node plate and an angle steel member, wherein the first stress-bearing node plate and the second stress-bearing node plate are respectively connected with two limb surface bolts of the angle steel member, and the first stress-bearing node plate and the second stress-bearing node plate are used to connect at least two angle steel members by a double-sided connection method; the method comprises:

[0010] According to the transmission tower load information, the actual internal force of the double-sided bolt node under various operating conditions is obtained;

[0011] Determine the main load-bearing limb and the secondary load-bearing limb of the angle steel member according to the specifications of the angle steel member; in the first load-bearing node plate and the second load-bearing node plate, define the load-bearing node plate connected to the main load-bearing limb as the main load-bearing node plate, and define the load-bearing node plate connected to the secondary load-bearing limb as the secondary load-bearing node plate;

[0012] The calculated thickness of the main load-bearing node plate is determined according to the maximum limb thickness of the limbs of several angle steel members connected to the main load-bearing node plate; the calculated thickness of the secondary load-bearing node plate is determined according to the maximum limb thickness of the limbs of several angle steel members connected to the secondary load-bearing node plate;

[0013] Calculate the theoretical connection stiffness of the main load-bearing node plate and the secondary load-bearing node plate according to the elastic modulus and calculated thickness of each load-bearing node plate;

[0014] According to the theoretical connection stiffness, the theoretical number of connecting bolts on each load node plate when the double-sided bolt node can bear the most unfavorable internal force is calculated.

[0015] The double-sided bolt node design method applied to the smart grid according to the above technical solution of the present invention may also have the following additional technical features:

[0016] In the above technical solution, the method of determining the calculated thickness of the main load-bearing node plate according to the maximum limb thickness of the limbs of a plurality of angle steel members connected to the main load-bearing node plate comprises:

[0017]

[0018] in, Indicates the calculated thickness of the main load-bearing node plate; represents the thickness of the connection limb of the i-th angle steel member connected to the main load-bearing node plate, and H represents a standard thickness specification;

[0019] The step of determining the calculated thickness of the secondary load-bearing node plate according to the maximum limb thickness of the limbs of a plurality of angle steel members connected to the secondary load-bearing node plate comprises:

[0020]

[0021] in, Indicates the calculated thickness of the secondary load node plate; It represents the thickness of the connection limb of the i-th angle steel member connected to the secondary load-bearing node plate, and H represents a standard thickness specification.

[0022] In the above technical solution, the calculation of the theoretical connection stiffness of the main load-bearing node plate and the secondary load-bearing node plate according to the elastic modulus and calculated thickness of each load-bearing node plate includes:

[0023]

[0024]

[0025] in, It represents the theoretical connection stiffness of the main load node plate; It represents the theoretical connection stiffness of the secondary load node plate; represents the elastic modulus of the main load-bearing node plate; represents the elastic modulus of the secondary load node plate; Indicates the cross-sectional area of ​​the main load-bearing node plate; It represents the cross-sectional area of ​​the secondary load node plate; Indicates the limb width of the angle steel member; Represents the secondary limb force transmission weakness coefficient.

[0026] In the above technical solution, the secondary limb force transmission attenuation coefficient is less than 1 and is related to the specifications of the connecting bolts on the load-bearing node plate.

[0027] In the above technical solution, the calculation of the theoretical number of connecting bolts on each load node plate when the double-sided bolt node can bear the most unfavorable internal force according to the theoretical connection stiffness includes:

[0028]

[0029]

[0030] in, Indicates the most unfavorable internal force of the double-sided bolt node; Indicates the theoretical number of connecting bolts on the main load-bearing node plate; Indicates the theoretical number of connecting bolts on the secondary load node plate; It represents the shear length reduction factor of the main load-bearing node plate connection bolts; It represents the shear length reduction factor of the secondary load node plate connection bolts; Indicates the shear bearing capacity of the bolt; Indicates the compressive bearing capacity of the screw.

[0031] In the above technical solution, the operating conditions include: normal operating conditions, installation conditions, icing conditions, line break accident conditions and uneven icing conditions.

[0032] In the above technical solution, the actual internal force borne by the double-sided bolt node under various operating conditions is obtained according to the load information of the transmission tower, including:

[0033] According to the three-dimensional model of the transmission tower and the known load information, the actual internal force of the double-sided bolt node under various operating conditions is calculated;

[0034] The maximum value of the internal forces corresponding to the double-sided bolt node under several operating conditions is taken as the most unfavorable internal force of the double-sided bolt node.

[0035] The present invention provides a double-sided bolt node evaluation method applied to a smart grid, comprising:

[0036] The double-sided bolt node design method applied to the smart grid as described in any of the above technical solutions is used to solve the theoretical number of connecting bolts on each stressed node plate in the double-sided bolt node to be evaluated; wherein the calculated thickness of each stressed node plate in the double-sided bolt node to be evaluated is assigned to the actual thickness of the stressed node plate;

[0037] Compare the theoretical number of connecting bolts on the load-bearing node plate with the actual number to determine whether the bearing capacity of the double-sided bolt node meets the operation requirements; when the calculated theoretical number of connecting bolts on the load-bearing node plate is less than or equal to the actual number of connecting bolts, it is determined that the bearing capacity of the double-sided bolt node can meet the operation requirements; otherwise, it is determined that the bearing capacity of the double-sided bolt node cannot meet the operation requirements.

[0038] The present invention provides a double-sided bolt node design and evaluation system for smart grids, which is applied to the design method described in any of the above technical solutions and the evaluation method described in the above technical solutions. The system includes:

[0039] A database storing basic data of transmission towers;

[0040] The node internal force calculation module is connected to the database, and uses the basic data of the transmission tower to calculate the internal force of each double-sided bolt node under different operating conditions according to the rod unit stiffness matrix;

[0041] The double-sided bolt node design and evaluation module is connected to the database and the node internal force calculation module respectively, and is used to determine the calculated thickness of each load-bearing node plate in the double-sided bolt node, and calculate the theoretical number of connecting bolts on each load-bearing node plate when the double-sided bolt node can bear the most unfavorable internal force according to the calculated thickness of the load-bearing node plate;

[0042] Among them, when designing a double-sided bolt node, the double-sided bolt node design and evaluation module outputs the calculated thickness of each load-bearing node plate and the theoretical number of connecting bolts on each load-bearing node plate as design data; when evaluating a double-sided bolt node, the double-sided bolt node design and evaluation module compares the theoretical number of connecting bolts on the load-bearing node plate with the actual number to determine whether the bearing capacity of the double-sided bolt node meets the operational requirements, and outputs the judgment result.

[0043] In the above technical solution, the database includes:

[0044] A load information database, at least used to store load information of a transmission tower;

[0045] A three-dimensional model library, at least for storing simulation models of transmission towers and components;

[0046] A component information library, at least used to store component specification information, component geometry information, and node location information;

[0047] The bolt information library is used to store at least bolt specification information, bolt shear strength information and bolt compressive strength information.

[0048] In summary, due to the adoption of the above technical features, the beneficial effects of the present invention are:

[0049] The present invention proposes a double-sided bolt node design method, evaluation method and design evaluation system applied to smart grids, which can realize the digital design and bearing capacity evaluation of double-sided bolt nodes of transmission lines, and has high design efficiency. Among them, the unbalanced characteristics of the two force-bearing surfaces in the double-sided bolt node are fully considered, and the calculation of the bearing capacity is designed according to its force transmission method, and the calculation of the bearing capacity is quantified as the number of connecting bolts on the force surface, which can be used as a design parameter in the design of the double-sided bolt node, and can also be used to evaluate the nodes that have been put into operation.

[0050] Additional aspects and advantages of the present invention will become apparent from the following description or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0052] Figure 1 It is a flow chart of a double-sided bolt node design method applied to a smart grid according to an embodiment of the present invention;

[0053] Figure 2 It is a schematic diagram of the principle of differentiating the stress-bearing limbs of angle steel in a double-sided bolt node design method applied to a smart grid according to an embodiment of the present invention;

[0054] Figure 3 It is a distribution diagram of a main force-bearing node plate and a secondary force-bearing node plate in a double-sided bolt node design method applied to a smart grid according to an embodiment of the present invention;

[0055] Figure 4 It is a module schematic diagram of a double-sided bolt node design and evaluation system applied to a smart grid according to an embodiment of the present invention. DETAILED DESCRIPTION

[0056] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0057] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0058] Refer to the following Figures 1 to 4 To describe the double-sided bolt node design, evaluation method and system for smart grid provided according to some embodiments of the present invention.

[0059] Some embodiments of the present application provide a double-sided bolt node design method for smart grid. The double-sided bolt node referred to in the present disclosure includes at least a first stress node plate, a second stress node plate and an angle steel member, wherein the first stress node plate and the second stress node plate are respectively connected to two limb surfaces of the angle steel member by bolts, and the first stress node plate and the second stress node plate are used to connect at least two angle steel members by double-sided connection; it can be understood that the first stress node plate and the second stress node are perpendicular to each other, and usually the two are not welded to each other, that is, they are in an independent state, and the first stress node plate and the second stress node are in corresponding positions, but the size specifications may be different; in actual application, in order to connect two separated angle steel members, only one node plate is used at the connection position to connect the two angle steel members as a conventional node; the research object of the present disclosure is a double-sided bolt node, that is, two node plates are used at the connection position to form a connection on the first plane and a connection on the second plane, the first plane is the coplanarity of the limb surfaces of several angle steel members, and the second plane is the coplanarity of the other limb surfaces of several angle steel members. Generally, the number of angle steel members to be connected is 2.

[0060] like Figure 1 As shown, the first embodiment of the present invention proposes a double-sided bolt node design method applied to a smart grid, including steps S1-S5.

[0061] S1. Obtain the actual internal force borne by the double-sided bolt node under various operating conditions based on the transmission tower load information.

[0062] In some embodiments, step S1 includes:

[0063] According to the three-dimensional model of the transmission tower and the known load information, the actual internal force borne by the double-sided bolt node under each operating condition is calculated; specifically, when designing the double-sided bolt node, the specific structure and load of the transmission tower are known data, and these data can be used to obtain the actual internal force borne by the double-sided bolt node through conventional calculation or simulation. For example, the internal force of each component is calculated based on the rod unit stiffness matrix. The specific calculation method or simulation method is well known to those skilled in the art, and is not an improvement of the present disclosure, and will not be repeated here.

[0064] The key point of step S1 is to obtain the actual internal force borne by the double-sided bolt node under different operating conditions and screen out the most unfavorable internal force. Specifically, the maximum value of the corresponding internal forces borne by the double-sided bolt node under several operating conditions is taken as the most unfavorable internal force of the double-sided bolt node.

[0065] In a specific embodiment, the operating conditions include: normal operating conditions, installation conditions, icing conditions, disconnection accident conditions, and uneven icing conditions. The above conditions are all common operating conditions of power transmission lines known to those skilled in the art.

[0066] S2. Determine the main load-bearing limb and the secondary load-bearing limb of the angle steel member according to the specifications of the angle steel member; in the first load-bearing node plate and the second load-bearing node plate, define the load-bearing node plate connected to the main load-bearing limb as the main load-bearing node plate, and define the load-bearing node plate connected to the secondary load-bearing limb as the secondary load-bearing node plate.

[0067] like Figure 2 As shown in the figure, the angle steel component has two limbs, of which the main limb bears greater axial force and shear force, and the secondary limb bears relatively smaller axial force and shear force. The main limb and the secondary limb are usually determined according to the specifications of the angle steel component. For example, the limb with a larger width in the unequal-leg angle steel is the main limb. For the transmission tower structure, the limb that bears the shear force in the positive direction is the main limb, that is, Figure 2 In the front of the angle steel member shown in the figure, the limb that bears the shear force laterally is the secondary force-bearing limb, that is, Figure 2 The top surface of the angle steel member is shown in . From this, the main load-bearing node plate and the secondary load-bearing node plate can be divided, as shown in Figure 3 As shown, it can be understood that the two angle steel members connected to the primary load-bearing node plate are connected through the primary load-bearing limbs. Similarly, the two angle steel members connected to the secondary load-bearing node plate are connected through the secondary load-bearing limbs.

[0068] S3. The calculated thickness of the main load-bearing node plate is determined based on the maximum limb thickness of the limbs of several angle steel members connected to the main load-bearing node plate; the calculated thickness of the secondary load-bearing node plate is determined based on the maximum limb thickness of the limbs of several angle steel members connected to the secondary load-bearing node plate.

[0069] The two angle steel members to be connected may have unequal leg thicknesses. To ensure the strength of the load-bearing node plate, the thickness of the load-bearing node plate should be designed based on the maximum leg thickness.

[0070] In a specific embodiment, the method of determining the calculated thickness of the main load-bearing node plate according to the maximum limb thickness of the limbs of a plurality of angle steel members connected to the main load-bearing node plate comprises:

[0071]

[0072] in, Indicates the calculated thickness of the main load-bearing node plate; It represents the thickness of the connecting limb of the i-th angle steel member connected to the main load-bearing node plate, and H represents a standard thickness specification.

[0073] The step of determining the calculated thickness of the secondary load-bearing node plate according to the maximum limb thickness of the limbs of a plurality of angle steel members connected to the secondary load-bearing node plate comprises:

[0074]

[0075] in, Indicates the calculated thickness of the secondary load node plate; It represents the thickness of the connection limb of the i-th angle steel member connected to the secondary load-bearing node plate, and H represents a standard thickness specification.

[0076] In this embodiment, H is superimposed on the maximum limb thickness, so that the thickness of the load-bearing node plate is one thickness specification larger than the limb thickness of the angle steel member connected thereto.

[0077] S4. Calculate the theoretical connection stiffness of the main load-bearing node plates and the secondary load-bearing node plates based on the elastic modulus and calculated thickness of each load-bearing node plate.

[0078] Since the primary load-bearing node plate and the secondary load-bearing node plate are not welded to each other, when they are separated from each other, their force transmission is related to the force transmission stiffness and the secondary limb force transmission attenuation coefficient. In some embodiments, step S4 includes:

[0079]

[0080]

[0081] in, It represents the theoretical connection stiffness of the main load node plate; It represents the theoretical connection stiffness of the secondary load node plate; represents the elastic modulus of the main load-bearing node plate; represents the elastic modulus of the secondary load node plate; Indicates the cross-sectional area of ​​the main load-bearing node plate; It represents the cross-sectional area of ​​the secondary load node plate; Indicates the limb width of the angle steel member; Represents the secondary limb force transmission weakness coefficient.

[0082] Specifically, the secondary limb force transmission attenuation coefficient is less than 1 and is related to the specification of the connecting bolts on the load-bearing node plate. In a specific embodiment, for M16 specification bolts Take 0.75 for M20 and M24 bolts Take 0.8.

[0083] S5. Based on the theoretical connection stiffness, calculate the theoretical number of connecting bolts on each load-bearing node plate when the double-sided bolt node can bear the most unfavorable internal force.

[0084] In some embodiments, step S5 includes:

[0085]

[0086]

[0087] in, represents the most unfavorable internal force of the double-sided bolt node, which can be determined by step S1; Indicates the theoretical number of connecting bolts on the main load-bearing node plate; Indicates the theoretical number of connecting bolts on the secondary load node plate; It indicates the shear length reduction factor of the main load-bearing node plate connection bolts, which is determined according to the steel structure design standard; It indicates the shear length reduction factor of the secondary load node plate connection bolts, which is determined according to the steel structure design standard; Indicates the shear bearing capacity of the bolt, which is determined according to the steel structure design standard; Indicates the compressive bearing capacity of the screw, which is determined according to the steel structure design standard.

[0088] Through the above design process, the calculated thickness of the main load-bearing node plate and the secondary load-bearing node plate in the double-sided bolt node, as well as the theoretical number of connecting bolts on the main load-bearing node plate and the secondary load-bearing node plate can be obtained. In other words, the double-sided bolt node designed according to the above parameters can well cope with the situation when the double-sided bolt node is subjected to the most unfavorable internal force, ensuring the reliability and stability of the double-sided bolt node.

[0089] A second embodiment of the present invention provides a double-sided bolt node evaluation method applied to a smart grid, comprising:

[0090] The double-sided bolt node design method applied to smart grid as described in the first embodiment above is used to solve the theoretical number of connecting bolts on each stressed node plate in the double-sided bolt node to be evaluated; however, since the evaluation is being conducted on a double-sided bolt node that has been put into operation or completed in design, the thickness of its stressed node plate and the number of bolts on each stressed node plate are both known values. Therefore, there is no need to perform step S3, and the calculated thickness of each stressed node plate in the double-sided bolt node to be evaluated can be directly assigned to the actual thickness of the stressed node plate; the calculations of steps S4 and S5 are performed according to the actual thickness of the stressed node plate to obtain the theoretical number of connecting bolts on each stressed node plate.

[0091] Subsequently, the theoretical number of connecting bolts on the load-bearing node plate is compared with the actual number to determine whether the bearing capacity of the double-sided bolt node meets the operation needs; when the calculated theoretical number of connecting bolts on the load-bearing node plate is less than or equal to the actual number of connecting bolts, it is determined that the bearing capacity of the double-sided bolt node to be evaluated can meet the operation needs; otherwise, it is determined that the bearing capacity of the double-sided bolt node to be evaluated cannot meet the operation needs.

[0092] The third embodiment of the present invention provides a double-sided bolt node design and evaluation system for smart grids, which is applied to the design method described in any of the above embodiments and the evaluation method described in the above second embodiment, such as Figure 4 As shown, the system includes: a database, a node internal force calculation module, a double-sided bolt node design evaluation module and a result output terminal.

[0093] The database stores basic data of transmission towers. Specifically, the database includes a load information library, a three-dimensional model library, a component information library and a bolt information library. The load information library is at least used to store the load information of the transmission tower; the three-dimensional model library is at least used to store the simulation models of the transmission tower and the components; the component information library is at least used to store component specification information, component geometry information, and node position information; the bolt information library is at least used to store bolt specification information, bolt shear strength information, and bolt compressive strength information. It can be understood that the database is mainly used to store known data information of the transmission tower, including shape parameters, material parameters, operating parameters, etc. The form of the above database is not unique, but this method can facilitate data call.

[0094] The node internal force calculation module is connected to the database, and uses the basic data of the transmission tower to calculate the internal force of each double-sided bolt node under different operating conditions according to the rod unit stiffness matrix.

[0095] The double-sided bolt node design and evaluation module is connected to the database and the node internal force calculation module respectively, and is used to determine the calculated thickness of each load-bearing node plate in the double-sided bolt node, and calculate the theoretical number of connecting bolts on each load-bearing node plate when the double-sided bolt node can bear the most unfavorable internal force based on the calculated thickness of the load-bearing node plate.

[0096] Among them, when designing a double-sided bolt node, the double-sided bolt node design and evaluation module outputs the calculated thickness of each load-bearing node plate and the theoretical number of connecting bolts on each load-bearing node plate as design data; when evaluating a double-sided bolt node, the double-sided bolt node design and evaluation module compares the theoretical number of connecting bolts on the load-bearing node plate with the actual number to determine whether the bearing capacity of the double-sided bolt node meets the operational requirements, and outputs the judgment result.

[0097] In a specific embodiment, if a double-sided bolt node design command is executed, after the result output terminal receives the result data stream transmitted by the double-sided bolt node design evaluation module, the terminal will generate a final design calculation report, and after approval, signature, and stamping by various levels within the design, the design calculation book (pdf encrypted format) and node drawings (pdf encrypted format) will be output; if a double-sided bolt node bearing capacity evaluation command is executed, the result output terminal will upload the evaluation results to the owner, waiting for the owner to make final instructions on the evaluation results, including "the evaluation results meet the requirements, continue to operate", "the evaluation results do not meet the requirements, and transformation and reinforcement are required". After the owner's instructions are confirmed, the terminal will generate a final evaluation analysis report, and after process approval, signature, and stamping by various levels within the owner, the final finished product report (pdf encrypted format) will be output for reference by the owner, design, construction, and operation and maintenance.

[0098] In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0099] Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A double-sided bolt node design method for smart grid, wherein the double-sided bolt node comprises at least a first stress node plate, a second stress node plate and an angle steel member, wherein the first stress node plate and the second stress node plate are respectively connected with two side bolts of the angle steel member, and the first stress node plate and the second stress node plate are used to connect at least two angle steel members by double-sided connection; characterized in that: The method comprises: According to the load information of the transmission tower, the actual internal force borne by the double-sided bolt node under various operating conditions is obtained; the operating conditions include: normal operating conditions, installation conditions, icing conditions, disconnection accident conditions and uneven icing conditions; Determine the main load-bearing limb and the secondary load-bearing limb of the angle steel member according to the specifications of the angle steel member; in the first load-bearing node plate and the second load-bearing node plate, define the load-bearing node plate connected to the main load-bearing limb as the main load-bearing node plate, and define the load-bearing node plate connected to the secondary load-bearing limb as the secondary load-bearing node plate; The calculated thickness of the main load-bearing node plate is determined according to the maximum limb thickness of the limbs of several angle steel members connected to the main load-bearing node plate; the calculated thickness of the secondary load-bearing node plate is determined according to the maximum limb thickness of the limbs of several angle steel members connected to the secondary load-bearing node plate; Calculate the theoretical connection stiffness of the main load-bearing node plate and the secondary load-bearing node plate according to the elastic modulus and calculated thickness of each load-bearing node plate; According to the theoretical connection stiffness, the theoretical number of connecting bolts on each load node plate when the double-sided bolt node can bear the most unfavorable internal force is calculated; The actual internal force borne by the double-sided bolt node under various operating conditions is obtained according to the transmission tower load information, including: According to the three-dimensional model of the transmission tower and the known load information, the actual internal force of the double-sided bolt node under various operating conditions is calculated; The maximum value of the internal forces corresponding to the double-sided bolt node under several operating conditions is taken as the most unfavorable internal force of the double-sided bolt node.

2. The double-sided bolt node design method for smart grid according to claim 1 is characterized in that: The method of determining the calculated thickness of the main load-bearing node plate according to the maximum limb thickness of the limbs of a plurality of angle steel members connected to the main load-bearing node plate comprises: in, Indicates the calculated thickness of the main load-bearing node plate; represents the thickness of the connection limb of the i-th angle steel member connected to the main load-bearing node plate, and H represents a standard thickness specification; The step of determining the calculated thickness of the secondary load-bearing node plate according to the maximum limb thickness of the limbs of a plurality of angle steel members connected to the secondary load-bearing node plate comprises: in, Indicates the calculated thickness of the secondary load node plate; It represents the thickness of the connection limb of the i-th angle steel member connected to the secondary load-bearing node plate, and H represents a standard thickness specification.

3. The double-sided bolt node design method for smart grid according to claim 2 is characterized in that: The method of calculating the theoretical connection stiffness of the main load-bearing node plate and the secondary load-bearing node plate according to the elastic modulus and calculated thickness of each load-bearing node plate includes: in, It represents the theoretical connection stiffness of the main load node plate; It represents the theoretical connection stiffness of the secondary load node plate; represents the elastic modulus of the main load-bearing node plate; represents the elastic modulus of the secondary load node plate; Indicates the cross-sectional area of ​​the main load-bearing node plate; It represents the cross-sectional area of ​​the secondary load node plate; Indicates the limb width of the angle steel member; Represents the secondary limb force transmission weakness coefficient.

4. The double-sided bolt node design method for smart grid according to claim 3 is characterized in that: The secondary limb force transmission attenuation coefficient is less than 1 and is related to the specifications of the connecting bolts on the load-bearing node plate.

5. The double-sided bolt node design method for smart grid according to claim 3 is characterized in that: The calculation of the theoretical number of connecting bolts on each load node plate when the double-sided bolt node can bear the most unfavorable internal force based on the theoretical connection stiffness includes: in, Indicates the most unfavorable internal force of the double-sided bolt node; Indicates the theoretical number of connecting bolts on the main load-bearing node plate; Indicates the theoretical number of connecting bolts on the secondary load node plate; It represents the shear length reduction factor of the main load-bearing node plate connection bolts; It represents the shear length reduction factor of the secondary load node plate connection bolts; Indicates the shear bearing capacity of the bolt; Indicates the compressive bearing capacity of the screw.

6. A double-sided bolt node evaluation method applied to smart grid, characterized in that: include: The double-sided bolt node design method applied to smart grid according to any one of claims 1 to 5 is used to solve the theoretical number of connecting bolts on each stressed node plate in the double-sided bolt node to be evaluated; wherein the calculated thickness of each stressed node plate in the double-sided bolt node to be evaluated is assigned to the actual thickness of the stressed node plate; Compare the theoretical number of connecting bolts on the load-bearing node plate with the actual number to determine whether the bearing capacity of the double-sided bolt node meets the operation requirements; when the calculated theoretical number of connecting bolts on the load-bearing node plate is less than or equal to the actual number of connecting bolts, it is determined that the bearing capacity of the double-sided bolt node can meet the operation requirements; otherwise, it is determined that the bearing capacity of the double-sided bolt node cannot meet the operation requirements.

7. A double-sided bolt node design and evaluation system for smart grid, characterized in that: Applied to the design method according to any one of claims 1 to 5 and the evaluation method according to claim 6, the system comprises: A database storing basic data of transmission towers; The node internal force calculation module is connected to the database, and uses the basic data of the transmission tower to calculate the internal force of each double-sided bolt node under different operating conditions according to the rod unit stiffness matrix; the operating conditions include: normal operating conditions, installation conditions, icing conditions, disconnection accident conditions and uneven icing conditions; wherein, according to the three-dimensional model of the transmission tower and the known load information, the actual internal force borne by the double-sided bolt node under each operating condition is calculated; the maximum value of the corresponding internal forces borne by the double-sided bolt node under several operating conditions is taken as the most unfavorable internal force of the double-sided bolt node; The double-sided bolt node design and evaluation module is connected to the database and the node internal force calculation module respectively, and is used to determine the calculated thickness of each load-bearing node plate in the double-sided bolt node, and calculate the theoretical number of connecting bolts on each load-bearing node plate when the double-sided bolt node can bear the most unfavorable internal force according to the calculated thickness of the load-bearing node plate; Among them, when designing a double-sided bolt node, the double-sided bolt node design and evaluation module outputs the calculated thickness of each load-bearing node plate and the theoretical number of connecting bolts on each load-bearing node plate as design data; when evaluating a double-sided bolt node, the double-sided bolt node design and evaluation module compares the theoretical number of connecting bolts on the load-bearing node plate with the actual number to determine whether the bearing capacity of the double-sided bolt node meets the operational requirements, and outputs the judgment result.

8. The double-sided bolt node design and evaluation system for smart grid according to claim 7, characterized in that: The database includes: A load information database, at least used to store load information of a transmission tower; A three-dimensional model library, at least for storing simulation models of transmission towers and components; A component information library, at least used to store component specification information, component geometry information, and node location information; The bolt information library is used to store at least bolt specification information, bolt shear strength information and bolt compressive strength information.

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