CN111159925B - Finite element analysis method and system for mechanical property evaluation of porcelain insulator - Google Patents
Finite element analysis method and system for mechanical property evaluation of porcelain insulator Download PDFInfo
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Abstract
The invention discloses a finite element analysis method, a finite element analysis system and a storage medium for mechanical property evaluation of a porcelain insulator under the condition of operating load, wherein the finite element analysis method comprises the following steps: establishing a geometric model of the single porcelain insulator; building a porcelain insulator string calculation model; establishing a power transmission conductor model by adopting a catenary equation; assembling the established model by adopting a multi-point constraint algorithm MPC to form a porcelain insulator string-power transmission wire coupling model; assigning material properties to each part of the porcelain insulator and the transmission conductor; carrying out finite element mesh subdivision on the ceramic insulator string-transmission conductor coupling model; defining a boundary, applying a load and setting a contact relation for the porcelain insulator string-transmission conductor coupling model; submitting the ceramic insulator string-transmission conductor finite element model to calculation; and extracting an analysis result and evaluating the mechanical property of the porcelain insulator. The method can be used for evaluating the mechanical safety of the extra-high voltage line large-tonnage insulator string, and provides a theoretical basis for the design and manufacture of the large-tonnage porcelain insulator string.
Description
Technical Field
The invention relates to the field of overhead power transmission line design, in particular to a finite element analysis method for mechanical property evaluation under a porcelain insulator running load condition.
Background
Along with the omnibearing and multidirectional striding type growth of economy in China in recent years, the corresponding requirements on the aspect of electric power energy are increased day by day. The porcelain insulator is an important basic insulating part in an extra-high voltage transmission line, and has the advantages of difficult aging, strong tensile resistance and long service life; the defect is that the mechanical performance deterioration fault is easy to occur due to long-term operation in a severe environment with coexistence of strong electric field, large mechanical stress, heavy pollution, complex temperature and humidity and the like. Once the porcelain insulator is degraded, the porcelain insulator can seriously threaten the stable operation of a power grid, accidents such as insulation flashover, string breakage and the like are caused to cause serious economic loss, and power grid disconnection, power supply and transformation equipment outage and even casualties are caused to be serious. It is therefore necessary to study the mechanical properties thereof under operating load conditions.
Under the operating condition, the tension insulator bears the tension of the wire, and the tension of the wire is influenced by various factors such as atmospheric conditions and use environments. When strong wind occurs, the tension of the wire can be increased sharply, and the operation safety of the insulator is seriously threatened. The current research on insulators mainly focuses on the electrical characteristics and windage yaw characteristics. Few documents only carry out simulation calculation on the mechanical characteristics of the single insulator under the condition of static load, do not consider the influence of a transmission conductor, and do not fully check the reliability under the condition of dynamic load. In addition, the porcelain insulator inevitably collides in the transportation, loading and unloading processes to cause cracks on the porcelain piece, the mechanical strength of the insulator is seriously weakened by the cracks, and designers usually pay more attention to the electrical performance of the porcelain piece and ignore the mechanical performance of the porcelain piece.
Therefore, a new technical solution is required to solve these problems.
Disclosure of Invention
The purpose of the invention is as follows: in order to overcome the defects in the prior art, the finite element analysis method for evaluating the mechanical performance of the porcelain insulator under the condition of the operating load is provided, the influence of dynamic loads such as a transmission conductor and wind load, ice coating, earthquake and the like can be considered, the method can be used for evaluating the mechanical safety of the extra-high voltage line large-tonnage insulator string, and a theoretical basis is provided for the design and manufacture of the large-tonnage porcelain insulator string.
The technical scheme is as follows: in order to achieve the purpose, the invention provides a finite element analysis method for evaluating mechanical properties of a porcelain insulator under the condition of operating load, which comprises the following steps:
s1: establishing a geometric model of the single porcelain insulator;
s2: establishing a porcelain insulator string calculation model based on a single-chip porcelain insulator geometric model, performing solid modeling on insulators at the end part of an iron tower, the end part of a lead, the middle of an insulator string and the position of the insulator with the defect on the model, and modeling the rest insulators by adopting a beam unit; establishing a power transmission conductor model by adopting a catenary equation;
s3: assembling the calculation model of the porcelain insulator string and the power transmission lead model established in the step S2, wherein the assembly adopts a multi-point constraint algorithm MPC to form a porcelain insulator string-power transmission lead coupling model;
s4: material attributes are specified for all parts of the porcelain insulator and the transmission conductor; carrying out finite element mesh subdivision on the ceramic insulator string-transmission conductor coupling model; defining a boundary, applying a load and setting a contact relation for a ceramic insulator string-power transmission conductor coupling model;
s5: submitting a finite element model of the porcelain insulator string-the transmission conductor to calculation on the basis of the boundary, the applied load and the contact relation defined in the step S4;
s6: and extracting a calculation result and evaluating the mechanical property of the porcelain insulator.
The geometric model of the single-piece porcelain insulator in the step S1 comprises parts such as porcelain pieces, steel caps, steel feet, cement, asphalt and the like.
The basis of modeling the porcelain insulator string in the step S2 is as follows: in structural design, the load acting on the porcelain insulator is borne by the steel cap, the steel feet, the head of the porcelain piece and the cement adhesive, and the deformation of the umbrella piece of the porcelain piece is small. Therefore, the stress deformation characteristics of the porcelain insulator sheet can be simulated by the beam unit.
The benefits of porcelain insulator string modeling in step S2 are: the mechanical characteristics of all parts in the insulators at the key positions can be accurately obtained, and the calculation scale can be reduced.
Further, the method for establishing the porcelain insulator string calculation model in the step S2 includes: the length of a beam unit is equivalent to the height of an insulator piece, the cross section of the beam is a circular cross section, the diameter of the upper section is the average diameter of a steel cap of the insulator piece, the diameter of the lower section is the diameter of a steel foot of the insulator piece, the property of a unit material is the same as that of the steel cap and the steel foot, the mass of the beam unit is equal to that of the insulator piece, a ceramic insulator string calculation model is formed, the equivalent density of the beam is calculated according to the mass of the insulator piece, the unit length and the unit diameter, the ceramic insulator string is formed by connecting a ball socket, certain rotation can occur at the joint, when the rotation reaches a certain degree, the rotation is limited, namely, a limited ball hinge is formed, and therefore when the beam unit is selected to simulate each insulator, the rotation freedom degree of the node also needs to be released and limited.
Further, the establishing of the power transmission lead model by using the catenary equation in the step S2 specifically includes the following steps:
s2-1: the transmission conductor is in a catenary state under the action of dead weight load, and the geometrical form of the transmission conductor is described by adopting a catenary equation:
in the formula: y is the ordinate of the calculation point, x is the abscissa of the calculation point, T is the horizontal tension of the wire, q is the gravity borne by the unit length of the wire, H is the span, and V is the hanging point height difference at the two ends of the wire;
s2-2: integrating equation (1) along a curve to obtain the length s of the power transmission conductor as follows:
s2-3: according to the elastic strain of the wire under the action of horizontal tension and gravity, the elastic elongation Δ s of the wire can be obtained as follows:
s2-4: the unstressed form transmission line length s can be obtained from the equations (3) and (4) 0 Comprises the following steps:
s 0 ＝s-Δs (5)
s2-5: the value of beta can be calculated by substituting T into formula (2), and then the wire length s under the stress-free condition can be obtained from formula (5) 0 Then move s 0 Calculation of beta in the unstressed state by substituting formula (3) 0 And finally, establishing a finite element model of the power transmission line in an unstressed state by the formula (1), wherein the finite element model is the actual shape of the power transmission line after the gravity load is applied.
Further, when the multipoint constraint algorithm MPC is adopted to assemble the porcelain insulator string and the power transmission conductor coupling model in step S3, the end points of the conductor model (beam unit) are selected as master nodes (guide nodes), the nodes on the end faces of the steel feet are selected as slave nodes, the contact algorithm MPC method is set, and the rotational degree of freedom of the nodes is released.
Furthermore, in the step S4, a second-order unit is selected to perform finite element mesh subdivision on the porcelain insulator string-power transmission conductor coupling model, so that the calculation accuracy can be improved. Because the quadratic unit has one more intermediate node than the first-order unit, the shape function of the unit uses quadratic polynomial interpolation, and the calculation precision is higher than that of the first order. When the secondary unit is adopted, the stress concentration phenomenon can be well obtained, and the second-order unit can well simulate the condition that the unit boundary is a curved edge, so that a curved surface can be accurately simulated by few units.
Further, the load applied in step S7 includes a wind load, an icing load and a seismic load, wherein the wind load is obtained by the following formula:
W 0 ＝ρv 2 /2
p h ＝αW 0 μ z μ sc d sin 2 θ
wherein, W 0 The standard value of the reference wind pressure is used; ρ is the air density and the standard value is 1.25kg/m 3 (ii) a v is the wind speed; p is a radical of h The horizontal wind load value of the lead in unit length vertical to the lead direction; alpha is the uneven coefficient of wind pressure; mu.s z Is the wind pressure height variation coefficient; mu.s sc Is the body shape factor of the wire; d is the outer diameter of the conductor, and the split conductor is the sum of the outer diameters of all sub-conductors; theta is an included angle between the wind direction and the direction of the lead or the ground wire;
the icing load was determined by the following equation:
q a ＝0.6·b·α 2 ·γ·10 -3
wherein q is a Is the ice coating load per unit area; b is the basic ice coating thickness; alpha (alpha) ("alpha") 2 The height increasing coefficient is the thickness of the ice; gamma is the icing severity and is generally 9KN/m 2 ；
The seismic load and the like are obtained by the following formulas:
in the formula: γ ═ 0.9+ (0.05- ξ)/(0.3+6 ξ), η 1 ＝0.02+(0.05-ξ)/(4+32ξ)，η 2 1+ (0.05-xi)/(0.08 +1.6 xi), and alpha is an earthquake influence coefficient; alpha is alpha max Is the maximum value of the earthquake influence coefficient; t is the structure natural vibration period; gamma is the attenuation index of the descending section of the curve; xi is the structural damping ratio; eta is a slope adjustment coefficient of the descending section; eta 2 The coefficient is adjusted for damping.
Further, the contact relationship set in step S4 includes frictional contact between the porcelain piece and the outer layer cement and frictional contact between the porcelain piece and the inner layer cement.
Further, when the mechanical properties of the porcelain insulator are evaluated in step S6, the steel cap and the steel leg are evaluated by using a fourth strength theory, and the cement and the porcelain are evaluated by using the first strength theory.
Further, the calculation result extracted in step S6 is a stress field, a strain field, and a displacement field distribution displayed graphically.
Has the advantages that: compared with the prior art, the finite element analysis method for mechanical property evaluation under the condition of the porcelain insulator running load is simple to operate, good in operability, stable in calculation result, high in accuracy, good in practicability and worthy of popularization, influences of dynamic loads such as power transmission conductors, wind loads, ice coating and earthquakes can be considered through a modeling and analyzing mode, mechanical safety of the extra-high voltage line large-tonnage insulator string can be evaluated, and a theoretical basis is provided for design and manufacture of the large-tonnage porcelain insulator string.
Drawings
FIG. 1 is a schematic flow diagram of the process of the present invention;
fig. 2 is a schematic structural diagram of a porcelain insulator according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a calculation model of an insulator string according to an embodiment of the present invention;
fig. 4 is a schematic diagram (1/2 model) of an insulator string-power transmission conductor coupling model provided by an embodiment of the invention.
Detailed Description
The invention is further elucidated with reference to the drawings and the embodiments.
As shown in fig. 1, the invention provides a finite element analysis method for mechanical property evaluation of a porcelain insulator under an operating load condition, which comprises the following steps:
s1: according to the porcelain insulator structure shown in the figure 2, a single-piece porcelain insulator geometric model is established and comprises parts such as a porcelain piece, a steel cap, a steel foot, cement, asphalt and the like, wherein the porcelain piece, the steel cap and the steel foot geometric model completes establishment of a solid model in CAD software according to a two-dimensional drawing, inner-layer cement of the three-umbrella insulator is formed by partially filling the inner surface of the three-umbrella insulator and the outer surface of the steel foot, and outer-layer cement of the three-umbrella insulator is formed by partially filling the outer surface of the three-umbrella insulator and the inner surface of the steel cap.
S2: the method comprises the following steps of establishing a porcelain insulator string calculation model, carrying out solid modeling on insulators at the end part of an iron tower, the end part of a lead, the middle of an insulator string and the position of a defective insulator on the model, and adopting a beam unit to model the rest insulators, wherein the specific establishment method comprises the following steps: the length of a beam unit is equivalent to the height of an insulator piece, the cross section of the beam is a circular cross section, the diameter of the upper section is the average diameter of a steel cap of the insulator piece, the diameter of the lower section is the diameter of a steel pin of the insulator piece, the property of a unit material is the same as that of the steel cap and the steel pin, the mass of the beam unit is equal to that of the insulator piece, the equivalent density of the beam is calculated according to the mass of the insulator piece, the diameter of the unit and the diameter of the unit, a ceramic insulator string is formed by connecting ball sockets, certain rotation can occur at the connecting part, when the rotation reaches a certain degree, the rotation is limited, and the rotation is equivalent to a limited ball hinge, so when the beam unit is selected to simulate each insulator, the rotational freedom degree of a node also needs to be released and limited;
establishing a power transmission lead model by adopting a catenary equation, which specifically comprises the following steps of S2-1-S2-5:
s2-1: the transmission conductor is in a catenary state under the action of dead weight load, and the geometrical form of the transmission conductor is described by adopting a catenary equation:
in the formula: y is the ordinate of the calculation point, x is the abscissa of the calculation point, T is the horizontal tension of the wire, q is the gravity borne by the unit length of the wire, H is the span, and V is the hanging point height difference at the two ends of the wire;
s2-2: integrating equation (1) along a curve to obtain the length s of the power transmission conductor as follows:
s2-3: according to the elastic strain of the wire under the action of horizontal tension and gravity, the elastic elongation Δ s of the wire can be obtained as follows:
s2-4: the unstressed form transmission line length s can be obtained from the equations (3) and (4) 0 Comprises the following steps:
s 0 ＝s-Δs (5)
s2-5: the value of beta can be calculated by substituting T into formula (2), and then the wire length s under the stress-free condition can be obtained from formula (5) 0 Then move s 0 Calculation of beta in the unstressed state by substituting formula (3) 0 And finally, establishing a finite element model of the power transmission line in an unstressed state by the formula (1), wherein the finite element model is the actual shape of the power transmission line after the gravity load is applied.
S3: referring to fig. 3, the model established in step S2 is assembled, the end points of the wire model (beam unit) are selected as master nodes (guide nodes), the nodes on the end surfaces of the steel legs are selected as slave nodes, the contact algorithm is set as the MPC method, and the rotational degrees of freedom of the nodes are released, so as to form a ceramic insulator string-transmission wire coupling model, and the concrete model is shown in fig. 4.
S4: and (5) assigning material properties to each part of the porcelain insulator and the transmission conductor.
S5: selecting a second-order unit to carry out finite element mesh subdivision on the porcelain insulator string-transmission conductor coupling model;
s6: defining a boundary, applying a load and setting a contact relation for a porcelain insulator string-power transmission conductor coupling model:
wherein the applied load comprises a wind load, an ice coating load and a seismic load, wherein the wind load is calculated by the following formula:
W 0 ＝ρv 2 /2
p h ＝αW 0 μ z μ sc d sin 2 θ
wherein, W 0 The standard value of the reference wind pressure is used; ρ is the air density and the standard value is 1.25kg/m 3 (ii) a v is the wind speed; p is a radical of h The horizontal wind load value of the lead in unit length vertical to the lead direction; alpha is the uneven coefficient of wind pressure; mu.s z Is the wind pressure height variation coefficient; mu.s sc Is the body shape factor of the wire; d is the outer diameter of the conductor, and the split conductor is the sum of the outer diameters of all sub-conductors; theta is an included angle between the wind direction and the direction of the lead or the ground wire;
the icing load was determined by the following equation:
q a ＝0.6·b·α 2 ·γ·10 -3
wherein q is a Is the ice coating load per unit area; b is the basic ice coating thickness; alpha (alpha) ("alpha") 2 The height increasing coefficient is the thickness of the ice; gamma is the icing severity, 9KN/m in this example 2 ；
The seismic load and the like are obtained by the following formulas:
in the formula: γ ═ 0.9+ (0.05- ξ)/(0.3+6 ξ), η 1 ＝0.02+(0.05-ξ)/(4+32ξ)，η 2 1+ (0.05-xi)/(0.08 +1.6 xi), and alpha is an earthquake influence coefficient; alpha is alpha max Is the maximum value of the earthquake influence coefficient; t is the structure natural vibration period; gamma is the attenuation index of the descending section of the curve; xi is the structural damping ratio; eta is a slope adjustment coefficient of the descending section; eta 2 The damping adjustment coefficient;
the contact relationship includes the friction contact between the porcelain piece and the outer layer cement and the friction contact between the porcelain piece and the inner layer cement.
S7: submitting the ceramic insulator string-transmission conductor finite element model to calculation;
s8: performing calculation post-processing to read a calculation result, judging whether the calculation result is reasonable, if so, extracting the calculation result, displaying the distribution of a stress field, a strain field and a displacement field through a graph, and evaluating the mechanical property of the porcelain insulator; if not, the process returns to step S1 again.
The embodiment also provides a finite element analysis system for mechanical property evaluation under the condition of ceramic insulator running load, which comprises a network interface, a memory and a processor; the network interface is used for receiving and sending signals in the process of receiving and sending information with other external network elements; a memory for storing computer program instructions executable on the processor; a processor for executing the steps of the finite element analysis method described above when executing the computer program instructions.
The present embodiment also provides a computer storage medium storing a computer program that when executed by a processor can implement the method described above. The computer-readable medium may be considered tangible and non-transitory. Non-limiting examples of a non-transitory tangible computer-readable medium include a non-volatile memory circuit (e.g., a flash memory circuit, an erasable programmable read only memory circuit, or a mask read only memory circuit), a volatile memory circuit (e.g., a static random access memory circuit or a dynamic random access memory circuit), a magnetic storage medium (e.g., an analog or digital tape or hard drive), an optical storage medium (e.g., a CD, DVD, or blu-ray disc), and so forth. The computer program includes processor-executable instructions stored on at least one non-transitory tangible computer-readable medium. The computer program may also comprise or rely on stored data. The computer programs may include a basic input/output system (BIOS) that interacts with the hardware of the special purpose computer, a device driver that interacts with specific devices of the special purpose computer, one or more operating systems, user applications, background services, background applications, and the like.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
Claims (7)
1. A finite element analysis method for mechanical property evaluation of a porcelain insulator under the condition of operating load is characterized by comprising the following steps: the method comprises the following steps:
s1: establishing a geometric model of the single porcelain insulator;
s2: building a porcelain insulator string calculation model based on a single-chip porcelain insulator geometric model, carrying out solid modeling on insulators at the end part of an iron tower, the end part of a lead, the middle of an insulator string and the position of a defective insulator on the model, and modeling the rest insulators by adopting a beam unit; establishing a power transmission conductor model by adopting a catenary equation;
s3: assembling the calculation model of the porcelain insulator string and the power transmission lead model established in the step S2, wherein the assembly adopts a multi-point constraint algorithm MPC to form a porcelain insulator string-power transmission lead coupling model;
s4: carrying out finite element mesh subdivision on the ceramic insulator string-transmission conductor coupling model; defining a boundary, applying a load and setting a contact relation for the porcelain insulator string-transmission conductor coupling model;
s5: submitting a finite element model of the porcelain insulator string-the transmission conductor to calculation on the basis of the boundary, the applied load and the contact relation defined in the step S4;
s6: extracting a calculation result and evaluating the mechanical property of the porcelain insulator;
the establishing of the power transmission conductor model by using the catenary equation in the step S2 specifically includes the following steps:
s2-1: the transmission conductor is in a catenary state under the action of dead weight load, and the geometrical form of the transmission conductor is described by adopting a catenary equation:
in the formula: y is the ordinate of the calculation point, x is the abscissa of the calculation point, T is the horizontal tension of the wire, q is the gravity borne by the unit length of the wire, H is the span, and V is the hanging point height difference at the two ends of the wire;
s2-2: integrating equation (1) along a curve to obtain the length s of the power transmission conductor as follows:
s2-3: according to the elastic strain of the wire under the action of horizontal tension and gravity, the elastic elongation Δ s of the wire can be obtained as follows:
s2-4: the unstressed form transmission line length s can be obtained from the equations (3) and (4) 0 Comprises the following steps:
s 0 ＝s-Δs (5)
s2-5: the value of beta can be calculated by substituting T into formula (2), and then the wire length s under the stress-free condition can be obtained from formula (5) 0 Then move s 0 Calculation of beta in the unstressed state by substituting formula (3) 0 Finally, a finite element model of the power transmission line in the stress-free state can be established through the formula (1), and the power transmission line is in the actual shape after gravity load is applied;
the load applied in step S4 includes a wind load, an icing load, and a seismic load, wherein the wind load is determined by the following formula:
W 0 ＝ρv 2 /2
p h ＝αW 0 μ z μ sc d sin 2 θ
wherein, W 0 The standard value of the reference wind pressure is used; ρ is the air density; v is the wind speed; p is a radical of h The horizontal wind load value of the lead in unit length vertical to the lead direction; alpha is the uneven coefficient of wind pressure; mu.s z Is the wind pressure height variation coefficient; mu.s sc Is the body shape factor of the wire; d is the outer diameter of the conductor, and the split conductor is the sum of the outer diameters of all sub-conductors; theta is an included angle between the wind direction and the direction of the lead or the ground wire;
the icing load was determined by the following equation:
q a ＝0.6·b·α 2 ·γ·10 -3
wherein q is a Is the ice coating load per unit area; b is the basic ice coating thickness; alpha (alpha) ("alpha") 2 The height increasing coefficient is the thickness of the ice; gamma is the icing severity;
the seismic load is determined by the following equation:
in the formula: γ ═ 0.9+ (0.05- ξ)/(0.3+6 ξ), η 1 ＝0.02+(0.05-ξ)/(4+32ξ)，η 2 1+ (0.05-xi)/(0.08 +1.6 xi), and alpha is an earthquake influence coefficient; alpha (alpha) ("alpha") max Is the maximum value of the earthquake influence coefficient; t is the structure natural vibration period; gamma is the attenuation index of the descending section of the curve; xi is the structural damping ratio; eta is a slope adjustment coefficient of the descending section; eta 2 The coefficient is adjusted for damping.
2. The finite element analysis method for mechanical property evaluation of the porcelain insulator under the condition of operating load according to claim 1, which is characterized in that: the method for establishing the porcelain insulator string calculation model in the step S2 comprises the following steps: the length of the beam unit is equivalent to the height of the insulator sheet, the cross section of the beam is a circular cross section, the diameter of the upper section is the average diameter of the steel cap of the insulator sheet, the diameter of the lower section is the diameter of the steel foot of the insulator sheet, the material property of the unit is the same as that of the steel cap and the steel foot, and the mass of the beam unit is equal to that of the insulator sheet, so that a ceramic insulator string calculation model is formed.
3. The finite element analysis method for mechanical property evaluation of the porcelain insulator under the condition of operating load according to claim 1, which is characterized in that: when the multipoint constraint algorithm MPC is adopted to assemble the porcelain insulator string and the power transmission conductor coupling model in the step S3, the endpoint of the conductor model is selected as a master node, the node on the ball end face of the steel leg is selected as a slave node, the contact algorithm is set as the MPC method, and the rotational degree of freedom of the node is released.
4. The finite element analysis method for mechanical property evaluation of the porcelain insulator under the condition of operating load according to claim 1, which is characterized in that: and in the step S4, a second-order unit is selected to carry out finite element mesh subdivision on the porcelain insulator string-transmission conductor coupling model.
5. The finite element analysis method for mechanical property evaluation of the porcelain insulator under the condition of operating load according to claim 1, which is characterized in that: the contact relationship set in step S4 includes frictional contact between the porcelain piece and the outer layer cement and frictional contact between the porcelain piece and the inner layer cement.
6. The finite element analysis method for mechanical property evaluation of the porcelain insulator under the operating load condition according to claim 1, which is characterized in that: the calculation result extracted in step S6 is a graph showing the stress field, strain field, and displacement field distributions.
7. A finite element analysis system for mechanical property evaluation under porcelain insulator operation load condition is characterized in that: the system comprises a network interface, a memory and a processor; wherein the content of the first and second substances,
the network interface is used for receiving and sending signals in the process of sending and receiving information with other external network elements;
the memory to store computer program instructions operable on the processor;
the processor is used for executing the steps of the finite element analysis method for mechanical property evaluation of the porcelain insulator under the condition of operating load according to any one of claims 1-6 when the computer program instructions are run.
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