Electrode system for simultaneously carrying out variable-temperature stress aging on multiple turn-to-turn insulation structure samples and simulation method thereof

Abstract

The invention discloses an electrode system for simultaneously carrying out variable-temperature stress aging on a plurality of turn-to-turn insulation structure samples and a simulation method of the electrode system, and belongs to the technical field of insulation test simulation. The problem that in the prior art, a traditional variable-temperature stress aging test method adopting a reactor turn-to-turn insulation structure is low in test efficiency is solved. According to the method, a simulation model is established for the turn-to-turn insulation structure of the electric reactor, and a plurality of turn-to-turn insulation structures formed by at least three aluminum wires are obtained; an aluminum wire wound by epoxy glass fibers and a mold are assembled and designed to obtain an electrode system, a simulation test of variable temperature stress aging is carried out on the electrode system, namely, turn-to-turn insulation variable temperature stress aging treatment and an overvoltage tolerance life test of the reactor are carried out, variable temperature stress aging simulation is completed, and a simulation result is obtained. According to the method, the variable temperature stress aging test efficiency of the turn-to-turn insulation structure is effectively improved, the test safety is higher by adopting simulation, and the method can be applied to the variable temperature stress aging test.

Description

Technical Field

[0001] The present invention relates to an electrode system and a simulation method thereof, and in particular to an electrode system and a simulation method thereof for simultaneously performing variable temperature stress aging on multiple inter-turn insulation structure samples, and belongs to the technical field of insulation test simulation. Background Art

[0002] With the rapid development of economy, high-voltage power transmission has become a hot topic nowadays. The design standards of ultra-high voltage and large power grid substations require a certain number of reactors to be connected in series or in parallel to adjust the reactive power of the power grid, so as to enhance the stability of the power system, improve the quality of power transmission and reduce line loss. The performance of the reactor is related to the safe operation of the power grid. Among them, the dry-type air-core reactor has the technical advantages of unsaturation, high strength, light weight, low noise and simple structure, and is widely used in the power system. When the reactor is put into operation, it often faces multi-factor aging, such as electrical aging, thermal aging, mechanical force and other environmental factors. The inter-turn insulation insulation part will gradually deteriorate and eventually fail. If it continues to operate, a short circuit will occur, causing the equipment to burn or the line to be cut off, threatening the operation of the power grid and the safety of users, and causing certain economic losses.

[0003] Variable temperature stress aging is the main part of the mechanical stress aging of the inter-turn insulation material of the reactor. The reason for this is that the thermal expansion coefficients of the various layers of materials constituting the insulation and the conductors are different, and the volume changes at different temperatures are also different, which causes the insulation to be subjected to extrusion stress at high temperatures and tensile stress at low temperatures. In actual operating conditions, the temperature of the insulation layer will change with usage, especially in my country's high-altitude and cold regions. The low temperature when not put into operation and the high temperature generated when high-voltage equipment is in operation form a relatively large temperature difference. After using the equipment many times, the insulation layer will be aged by variable temperature stress. Variable temperature stress will not directly damage the performance of the insulating material, but when microcracks exist after aging of the material, variable temperature stress will appear concentrated, which may exceed the material's bearing limit, causing crack expansion, causing air gap defects and even encapsulation insulation cracking.

[0004] At the same time, the months when reactors fail are mainly concentrated in winter, the time of inter-turn insulation failure has seasonal characteristics, and the fault location has a statistical regularity, that is, it is located in the relatively outer enclosure. Most insulation material performance specimens are sheet samples, but due to variable temperature stress aging, which is often a mechanical stress aging of tension-compression stress cycle that frequently occurs under actual working conditions, it is difficult to apply vertical tensile stress to sheet samples.

[0005] In summary, an electrode system and a simulation method thereof are needed for simulating a reactor inter-turn insulation structure specimen and for simultaneously performing variable temperature stress aging of multiple inter-turn insulation structure specimens. Summary of the invention

[0006] A brief overview of the present invention is provided below in order to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to identify key or important parts of the present invention, nor is it intended to limit the scope of the present invention. Its purpose is merely to present certain concepts in a simplified form as a prelude to a more detailed description discussed later.

[0007] In view of this, in order to solve the problem of low test efficiency of the traditional variable temperature stress aging test method using the inter-turn insulation structure of the reactor in the prior art, the present invention provides an electrode system and a simulation method thereof for simultaneously performing variable temperature stress aging of multiple inter-turn insulation structure specimens.

[0008] Technical solution 1 is as follows: A method for simulating an electrode system for simultaneously performing variable temperature stress aging of multiple inter-turn insulation structure specimens, comprising the following steps:

[0009] S1. Establish a simulation model for the inter-turn insulation structure of the reactor to obtain a plurality of inter-turn insulation structures consisting of at least three aluminum wires;

[0010] S2. Design the aluminum wire and mold assembly without epoxy glass filament winding to obtain the electrode system, conduct a simulation test of temperature-dependent stress aging, complete the temperature-dependent stress aging simulation and obtain the simulation results.

[0011] Further, in the S1, in the modeling software, a two-dimensional simulation modeling is performed on the arrangement of the single-layer multi-aluminum wire insulation structure, and according to the principal stress calculation formula, the first principal stress magnitude σ1, the second principal stress magnitude σ2 and the third principal stress magnitude σ3 of the two-dimensional plane are calculated, and the first principal stress magnitude σ1 and the third principal stress magnitude σ3 are subtracted to further obtain the principal stress difference Δσ, and finally multiple inter-turn insulation structures composed of multiple aluminum wires are obtained;

[0012] The principal stress calculation formula is expressed as:

[0013]

[0014] σ2=0

[0015]

[0016] Among them, σ x is the normal stress in the x-direction of the coordinate system in the two-dimensional plane, σ y is the normal stress in the y direction of the coordinate system in the two-dimensional plane;

[0017] The principal stress difference Δσ is expressed as:

[0018]

[0019] Among them, τ xy is the shear stress.

[0020] Further, in the S2, in the modeling software, a film-coated aluminum wire of the same material as the actual reactor is selected, the film-coated aluminum wire is inserted into a punched polytetrafluoroethylene block in parallel and arranged in an epoxy plate mold with a groove milled out, a release agent is sprayed on the inner surface of the mold, and then a syringe is used to fill the epoxy mold, the upper cover plate is covered, and a fixed metal rod is inserted to fix it. After curing for a certain period of time at a specific temperature, the mold is taken out, and the two ends of the film-coated aluminum wire are inserted into a hollow copper rod equalizing electrode with hemispherical ends to obtain an electrode system;

[0021] The temperature is changed under appropriate temperature difference, so that the electrode system is continuously subjected to variable temperature stress, and the inter-turn insulation of the reactor is subjected to variable temperature stress aging treatment, followed by an overvoltage life test. During the overvoltage life test, the entire mold is wrapped with glass fiber impregnated with epoxy resin.

[0022] Technical solution 2 is as follows: an electrode system for simultaneously performing variable temperature stress aging of multiple inter-turn insulation structure specimens, comprising a voltage-equalizing electrode, a first set of film-wrapped aluminum wires, a die, a polytetrafluoroethylene block, and a second set of film-wrapped aluminum wires;

[0023] The mold comprises an upper cover plate and a lower plate, the upper cover plate is connected to the lower plate, the lower plate is provided with a groove, and the polytetrafluoroethylene block is embedded in the groove;

[0024] The first group of film-coated aluminum wires horizontally penetrates the polytetrafluoroethylene block, and both ends are connected to the voltage-equalizing electrodes;

[0025] The second group of membrane-coated aluminum wires passes through the polytetrafluoroethylene block horizontally, and both ends are grounded.

[0026] Furthermore, the electrode system also includes a metal rod, which runs through the mold longitudinally.

[0027] The beneficial effects of the present invention are as follows: the present invention can simultaneously perform multiple turns and multiple pairs of electrodes to improve test efficiency, solve the problem of electrode centering and the complex assembly of multiple electrodes, facilitate wiring, and verify whether there is interference between multiple pairs of electrodes through simulation means, which is more efficient and improves the test safety factor. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0029] Figure 1 A schematic flow chart of an electrode system simulation method for simultaneously performing variable temperature stress aging of multiple inter-turn insulation structure specimens;

[0030] Figure 2 A schematic diagram of the structure of an electrode system for simultaneously performing variable temperature stress aging on multiple inter-turn insulation structure specimens;

[0031] Figure 3 The diagram is a diagram showing the relationship between the principal stress difference at 90°C and the principal stress difference at -40°C and the number of turns for turn-to-turn insulation with different numbers of turns;

[0032] Figure 4 This is a schematic diagram of the simulation of the stress condition of the insulation structure between turns of the reactor at -40℃;

[0033] Figure 5 It is a simulation diagram of the stress condition of the insulation structure of the reactor turns at 90°C;

[0034] Figure 6 is a top view of the lower plate;

[0035] Figure 7 It is the main view of the lower plate;

[0036] Figure 8 is a front view of the voltage-equalizing electrode;

[0037] Fig. 9 Schematic diagram of the hemispherical shell structure of the voltage-equalizing electrode;

[0038] Fig.10 Schematic diagram of the main structure of the voltage-equalizing electrode;

[0039] Fig.11 is the front view of the polytetrafluoroethylene block;

[0040] Fig.12 It is a perspective view of the polytetrafluoroethylene block and a top view of the lower plate;

[0041] Fig.13 The present invention is a schematic diagram of an embodiment of an electrode system for simultaneously performing variable temperature stress aging on multiple inter-turn insulation structure samples;

[0042] Fig.14 The present invention is a schematic flow chart of an embodiment of a method for simulating an electrode system for simultaneously performing variable temperature stress aging of multiple inter-turn insulation structure specimens.

[0043] Figure numerals: 1. voltage-equalizing electrode; 2. first group of membrane-wrapped aluminum wires; 3. metal rod; 4. upper cover plate; 5. polytetrafluoroethylene block; 6. lower plate; 7. second group of membrane-wrapped aluminum wires. DETAILED DESCRIPTION

[0044] In order to make the technical solutions and advantages of the embodiments of the present invention more clearly understood, the exemplary embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than an exhaustive list of all the embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0045] Example 1: Reference Figure 1-Figure 14 The present embodiment is described in detail. A method for simulating an electrode system for simultaneously performing variable temperature stress aging of multiple inter-turn insulation structure samples specifically includes the following steps:

[0046] S1. Establish a simulation model for the inter-turn insulation structure of the reactor to obtain a plurality of inter-turn insulation structures consisting of at least three aluminum wires;

[0047] S2. Design the aluminum wire and mold assembly without epoxy glass filament winding to obtain the electrode system, conduct a simulation test of temperature-dependent stress aging, complete the temperature-dependent stress aging simulation and obtain the simulation results.

[0048] Further, in the S1, in the modeling software, a two-dimensional simulation modeling is performed on the arrangement of the single-layer multi-aluminum wire insulation structure, and according to the principal stress calculation formula, the first principal stress magnitude σ1, the second principal stress magnitude σ2 and the third principal stress magnitude σ3 of the two-dimensional plane are calculated, and the first principal stress magnitude σ1 and the third principal stress magnitude σ3 are subtracted to further obtain the principal stress difference Δσ, and finally multiple inter-turn insulation structures composed of multiple aluminum wires are obtained;

[0049] The principal stress calculation formula is expressed as:

[0050]

[0051] σ2=0

[0052]

[0053] Among them, σ x is the normal stress in the x-direction of the coordinate system in the two-dimensional plane, σ y is the normal stress in the y direction of the coordinate system in the two-dimensional plane;

[0054] The principal stress difference Δσ is expressed as:

[0055]

[0056] Among them, τ xy is the shear stress;

[0057] Specifically, since the actual reactor structure is a multi-layer multi-coil parallel winding, and the structure of each section is the same, a two-dimensional simulation model is performed on the single-layer multi-aluminum wire insulation structure arrangement. The principal stress difference Δσ reflects the stress difference inside the material. The larger the principal stress, the greater the shear force on the material.

[0058] refer to Figure 3 The difference in principal stress magnitudes of inter-turn insulation of several turns at 90°C and -40°C is calculated by the principal stress calculation formula. It can be seen that if only two aluminum wires are used to make the structural specimen, the variable temperature stress magnitude between the turns is smaller than that of the multi-turn coil, and as the number of turns increases, the stress magnitude tends to be stable. Therefore, it is feasible to perform variable temperature stress aging of multiple inter-turn insulation at the same time. This embodiment chooses to design three inter-turn insulations composed of four aluminum wires because of its simple structure and convenient production.

[0059] Further, in the S2, in the modeling software, a film-coated aluminum wire of the same material as the actual reactor is selected, the film-coated aluminum wire is inserted into a punched polytetrafluoroethylene block in parallel and arranged in an epoxy plate mold with a groove milled out, a release agent is sprayed on the inner surface of the mold, and then a syringe is used to fill the epoxy mold, the upper cover plate is covered, and a fixed metal rod is inserted to fix it. After curing for a certain period of time at a specific temperature, the mold is taken out, and the two ends of the film-coated aluminum wire are inserted into a hollow copper rod equalizing electrode with hemispherical ends to obtain an electrode system;

[0060] The temperature is changed under a suitable temperature difference, so that the electrode system is continuously subjected to the effect of variable temperature stress, and the inter-turn insulation of the reactor is subjected to variable temperature stress aging treatment, followed by an overvoltage life test. During the overvoltage life test, the entire mold is wrapped with glass fiber impregnated with epoxy resin;

[0061] Specifically, refer to Figure 4 and Figure 5 ,The results show that the pressure is concentrated on the polyester film of the PTFE block 5, which is subjected to a compressive stress of about 17MPa at 90℃ and a tensile stress of about 16MPa at -40℃;

[0062] The sample model is made of the same film-wrapped aluminum wire as the actual reactor, with the following specifications: aluminum wire diameter 4.25mm, 3 layers of polyester film and one layer of non-woven fabric wrapped outside, and the diameter of the aluminum wire wrapped with the insulation layer is 4.7mm. The sample consists of four 300mm aluminum wires of the same length. Two non-adjacent aluminum wires are bent upward or downward. The bending angle should not be too large, and polyimide tape is wrapped at the bend to strengthen the insulation to prevent the insulation at the bend from being damaged and causing unnecessary insulation breakdown in the experiment. The two conductors in the middle are parallel, and the length of the parallel part is 100mm. The insulation layer at the end of the wire is removed to expose the aluminum wire for easy wiring. The exposed length is 20mm.

[0063] In order to be as close as possible to the real dry-type air-core reactor inter-turn insulation wet-winding structure, the model can also simulate the temperature-variable stress aging test of aluminum wire with or without epoxy glass fiber winding. It is only necessary to wind the glass fiber before pouring the epoxy resin, and then solidify and encapsulate it for aging. The present invention only simulates the inter-turn insulation structure without glass fiber winding;

[0064] The film-coated aluminum wire has good thermal conductivity, responds quickly to temperature changes in hot and cold cycles, and can make the temperature change of the inter-turn insulation faster;

[0065] The voltage-equalizing electrode can not only prevent corona discharge on the high-voltage side, but also prevent the wire from being bent and deformed by the voltage-equalizing electrode after long-term aging because both ends of the aluminum wire are inserted into the copper rod at the same time;

[0066] Thermal aging at a single temperature will not cause the insulation performance to decline, but it will significantly reduce the mechanical properties. Therefore, thermal aging treatment is required before variable temperature stress aging treatment. Mechanical stress aging is performed on the inter-turn insulation that has already experienced mechanical performance decline. The temperature is changed under a suitable temperature difference so that the inter-turn insulation is continuously subjected to variable temperature stress. The variable temperature stress aging treatment of the inter-turn insulation of the reactor is performed.

[0067] In order to reduce the embrittlement and aging of epoxy board molds caused by large temperature difference, an overvoltage life test after stress aging is carried out after being subjected to temperature change stress. Three inter-turn insulation structures are formed between the four wires. Each non-adjacent wire is connected to high voltage or ground at the same time, so that the three inter-turn insulations are cracked or damaged, which may have a greater impact on the experiment. Therefore, the bottom surface and side protrusions of the lower plate and the upper cover plate should be as thick as possible, that is, the thickness is greater than 15mm. At the same time, the entire mold is wrapped with glass fiber impregnated with epoxy resin, which can enhance its external mechanical properties, so that the internal stress distribution and size will not change with the increase of aging time, and the above experiment can be completed safely.

[0068] The specific steps of the experiment are as follows: After assembling the various components of the electrode system together, first perform thermal aging treatment. The operating temperature rise limit of the dry-type air-core reactor winding is 60K. Taking the average temperature of the environment as 20℃, the long-term maximum operating temperature of the reactor is 80℃. The life formula is obtained under the condition that the temperature range does not exceed the temperature rise limit of 185℃ when the dry-type air-core power reactor inter-turn insulation is subjected to accelerated thermal aging;

[0069] The lifespan formula is:

[0070]

[0071] Wherein, τ is the thermal aging life, t is the thermal aging temperature;

[0072] Then, the reactor is simulated to run at 80℃ for 10 years, and the aging temperature is set to 160℃. By substituting 80℃ and 160℃ into the life formula, the thermal aging life of the reactor turn-to-turn insulation is 1.224×102h and 3725h respectively. When the reactor actually runs at 80℃ for 15 years, it is equivalent to the time T when it runs at 160℃. 160 , we get the aging time formula, which means that the total aging time is 399 hours;

[0073] The aging time formula is expressed as:

[0074]

[0075] The inter-turn insulation simulating the degradation of mechanical properties of the reactor after aging can make the effect of the variable temperature stress aging test more obvious. After being placed in a variable temperature aging test box and given appropriate upper and lower temperature limits and temperature difference aging for a certain period, the motor system is taken out, and the two ends of the two high-voltage side aluminum wires are inserted into the round holes of the copper rod at the same time. The conductor is then wrapped around the middle of the two aluminum wires, and high voltage is passed to study the ability of the inter-turn insulation to withstand overvoltage affected by variable temperature stress.

[0076] Example 2: Reference Figure 1-Figure 14 The present embodiment is described in detail. An electrode system for simultaneously performing variable temperature stress aging on multiple inter-turn insulation structure samples is used to perform an electrode system simulation method for simultaneously performing variable temperature stress aging on multiple inter-turn insulation structure samples described in Embodiment 1, comprising a voltage-equalizing electrode 1, a first group of film-wrapped aluminum wires 2, a mold, a polytetrafluoroethylene block 5, and a second group of film-wrapped aluminum wires 7;

[0077] The mold comprises an upper cover plate 4 and a lower plate 6, the upper cover plate 4 is connected to the lower plate 6, the lower plate 6 is provided with a groove, and the polytetrafluoroethylene block 5 is embedded in the groove;

[0078] The first group of film-coated aluminum wires 2 transversely penetrate the polytetrafluoroethylene block 5, and both ends are connected to the voltage-equalizing electrode 1;

[0079] The second group of film-coated aluminum wires 7 transversely penetrate the polytetrafluoroethylene block 5 and are grounded at both ends.

[0080] Further, the electrode system also includes a metal rod 3, which runs through the mold longitudinally;

[0081] Specifically, in this embodiment, the first group of membrane-wrapped aluminum wires 2 and the second group of membrane-wrapped aluminum wires 7 are both two aluminum wires. Since the polytetrafluoroethylene block 5 has good heat resistance and electrical resistance, it is used as a fastener before the epoxy resin is cured to prevent the epoxy resin from overflowing, and the aluminum wire can also be restricted in a stable position. Four horizontally arranged circular holes with a diameter of 4.7 mm are milled out of two polytetrafluoroethylene blocks 5 with a length of 25 mm, a width of 6 mm, and a thickness of 5 mm. The center distance between adjacent circular holes is 5 mm. The four circular holes are arranged in the center of the polytetrafluoroethylene block 5, and four aluminum wires pass through the four circular holes.

[0082] refer to Figure 8-Figure 10 The voltage-equalizing electrode 1 is a copper rod voltage-equalizing electrode with hemispherical shells at both ends. The radius of the shell is 5 mm. The edge of the shell is extended by 5 mm and tapped with an M10 internal thread. The voltage-equalizing electrode 1 is provided with two circular holes with a diameter of 4.5 mm. The distance between the two circular holes is 3.5 mm. The size of the voltage-equalizing electrode 1 is 30 mm long.

[0083] refer to Figure 6 and Figure 7 The size of the lower plate 6 is 100mm long, 65mm wide, and 21mm thick. The lower plate 6 is a rectangular epoxy resin lower plate. The lower plate 6 is provided with a through hole with a depth of 21mm and a diameter of 6mm, which is used to match the metal rod 3 with a diameter of 6mm. The size of the groove is 100mm long, 25mm wide, and 6mm deep. The two ends of the groove are used to prevent the polytetrafluoroethylene blocks from flowing out of the epoxy resin. The distance from the left and right sides of the groove to the left and right sides of the epoxy plate is 20mm, and a through hole with a diameter of 6mm is punched in the middle of the protrusions on both sides.

[0084] The size of the upper cover plate 4 is 100 mm in length, 65 mm in width and 15 mm in thickness. The upper cover plate 4 is a rectangular epoxy resin upper cover plate. The upper cover plate 4 is provided with a through hole with a diameter of 6 mm, which is consistent with the hole position of the lower plate 6 .

[0085] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments may be envisioned within the scope of the invention thus described. In addition, it should be noted that the language used in this specification is selected primarily for readability and teaching purposes, rather than for explaining or defining the subject matter of the present invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the present invention is illustrative, not restrictive, with respect to the scope of the present invention, which is defined by the appended claims.

Claims

1. An electrode system simulation method for simultaneously performing variable temperature stress aging of multiple inter-turn insulation structure specimens, characterized in that: The following steps are involved: S1. Establish a simulation model for the inter-turn insulation structure of the reactor to obtain a plurality of inter-turn insulation structures consisting of at least three aluminum wires; S2. Design the aluminum wire and mold assembly without epoxy glass filament winding to obtain the electrode system, conduct a simulation test of temperature-dependent stress aging, complete the temperature-dependent stress aging simulation and obtain the simulation results.

2. The electrode system simulation method for simultaneously performing temperature-dependent stress aging of multiple inter-turn insulation structure specimens according to claim 1, characterized in that: In S1, in the modeling software, a two-dimensional simulation modeling is performed on the arrangement of a single-layer multi-aluminum wire insulation structure, and according to the principal stress calculation formula, the first principal stress magnitude σ1, the second principal stress magnitude σ2 and the third principal stress magnitude σ3 in the two-dimensional plane are calculated, and the first principal stress magnitude σ1 and the third principal stress magnitude σ3 are subtracted to further obtain the principal stress difference Δσ, and finally multiple inter-turn insulation structures composed of multiple aluminum wires are obtained; The principal stress calculation formula is expressed as: σ2=0 Among them, σ x is the normal stress in the x-direction of the coordinate system in the two-dimensional plane, σ y is the normal stress in the y direction of the coordinate system in the two-dimensional plane; The principal stress difference Δσ is expressed as: Among them, τ xy is the shear stress.

3. The electrode system simulation method for simultaneously performing variable temperature stress aging of multiple inter-turn insulation structure samples according to claim 2, characterized in that: In the S2, in the modeling software, a film-wrapped aluminum wire of the same material as the actual reactor is selected, the film-wrapped aluminum wire is inserted into a punched polytetrafluoroethylene block in parallel and arranged in an epoxy plate mold with a groove milled out, a release agent is sprayed on the inner surface of the mold, and then a syringe is used to fill the epoxy mold, the upper cover plate is covered, and a fixed metal rod is inserted to fix it. After curing for a certain period of time at a specific temperature, the mold is taken out, and both ends of the film-wrapped aluminum wire are inserted into a hollow copper rod equalizing electrode with hemispherical ends to obtain an electrode system; The temperature is changed under appropriate temperature difference, so that the electrode system is continuously subjected to variable temperature stress, and the inter-turn insulation of the reactor is subjected to variable temperature stress aging treatment, followed by an overvoltage life test. During the overvoltage life test, the entire mold is wrapped with glass fiber impregnated with epoxy resin.

4. An electrode system for simultaneously performing variable temperature stress aging on multiple inter-turn insulation structure samples, characterized in that: The electrode system simulation method for simultaneously performing variable temperature stress aging of multiple inter-turn insulation structure specimens as described in any one of claims 1 to 3 comprises a voltage-equalizing electrode (1), a first group of film-wrapped aluminum wires (2), a mold, a polytetrafluoroethylene block (5), and a second group of film-wrapped aluminum wires (7); The mold comprises an upper cover plate (4) and a lower plate (6), the upper cover plate (4) is connected to the lower plate (6), the lower plate (6) is provided with a groove, and the polytetrafluoroethylene block (5) is embedded in the groove; The first group of membrane-coated aluminum wires (2) transversely penetrate the polytetrafluoroethylene block (5), and both ends are connected to the voltage-equalizing electrode (1); The second group of membrane-coated aluminum wires (7) transversely penetrate the polytetrafluoroethylene block (5) and are grounded at both ends.

5. The electrode system for simultaneously performing temperature-variable stress aging on multiple inter-turn insulation structure samples according to claim 4, characterized in that: It also comprises a metal rod (3) which runs through the mold longitudinally.

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