High-temperature-resistant electricity-heat-vibration combined aging test electrode

Abstract

The invention relates to the technical field of high-voltage insulation, in particular to a high-temperature-resistant electricity-heat-vibration combined aging test electrode. The invention discloses a high-temperature-resistant electricity-heat-vibration combined aging test electrode which comprises a ground electrode, an inner cavity of the ground electrode is closed through a cover plate on the upper side, insulating oil is contained in the inner cavity, and the cover plate and the ground electrode are fixedly connected with a high-voltage electrode through a first nut. And the lower end of the high-voltage electrode penetrates through the first corundum sheet, the cover plate and the second corundum sheet and clings to the insulating sample. The high temperature resistance of the whole electrode is improved, the vibration resistance of the electrode is enhanced, and the accuracy and reliability of a combined aging test are improved. According to the invention, powerful support is provided for reliability evaluation of electrical equipment, materials or components.

Description

Technical Field

[0001] The invention relates to the field of high voltage and insulation technology, and in particular to a high temperature resistant electric-thermal-vibration combined aging test electrode. Background Art

[0002] When conducting oil-paper insulation aging tests, it is difficult for traditional electrodes to achieve the electric-thermal-vibration combined aging test of oil-paper insulation, and because the structural parts of traditional electrode devices have insufficient heat resistance, it is difficult to use traditional electrode devices to conduct tests when the thermal aging temperature exceeds 150°C.

[0003] The structural parts of the traditional aging test electrode device are mainly epoxy resin or acrylic, and its fixing method makes it difficult to transmit vibration to the oil-paper insulation sample, and it is difficult to meet the combined aging method of electric-thermal-vibration aging. At the same time, with the improvement of the temperature resistance level of oil-paper insulation, it is difficult for traditional electrodes to apply higher temperatures than 150°C, and the temperature that the oil-paper insulation sample under development needs to withstand in the accelerated aging experiment is at least 180°C, and the existing technology cannot meet the test requirements. In response to this phenomenon, the applicant has specially proposed a high-temperature resistant electric-thermal-vibration combined aging test electrode through long-term practice, so as to meet the combined aging method of electric-thermal-vibration aging, and at the same time, the upper limit of the thermal aging temperature when applying vibration and voltage during combined aging is increased from about 130°C of the traditional device to about 300°C. In addition, the assembly method and the position of the assembly parts have been carefully designed. When applying a 12kV power frequency AC test voltage, no discharge in the form of arc discharge will occur at the floating potential and other air gap structures, which meets the test requirements of electric-thermal-vibration combined aging at high temperature. Summary of the invention

[0004] In order to solve the existing technical problems, the present invention tests and evaluates the insulating sample by setting a high-voltage electrode, a ground electrode, a cover plate, a spring and two corundum sheets buckled together, thereby improving the accuracy and reliability of the combined aging test and providing strong support for the reliability evaluation of electrical equipment, materials or components.

[0005] In order to achieve the purpose of the invention, the present invention provides a high-temperature resistant electric-thermal-vibration combined aging test electrode, including a ground electrode whose inner cavity is sealed by a cover plate on the upper side, and the inner cavity is filled with insulating oil. It is characterized in that the cover plate and the ground electrode are fixedly connected to the high-voltage electrode through a first nut, and the lower end of the high-voltage electrode passes through a first corundum sheet, a cover plate and a second corundum sheet to be tightly attached to an insulating sample.

[0006] Preferably, a pressure equalizing ball is provided at the top of the high voltage electrode.

[0007] Preferably, a pressure plate is provided at the lower end of the high voltage electrode.

[0008] Preferably, a spring is provided between the lower ends of the high-voltage electrodes. The spring is made of a high-temperature resistant elastic alloy and is used to maintain the stability and contact of the high-voltage electrodes under temperature changes and vibration conditions.

[0009] Preferably, a boss is provided at the bottom of the inner cavity of the ground electrode, and the ground electrode and the boss are of an integral structure.

[0010] Preferably, the ground electrode is of a cylindrical structure, and screw holes are provided at the outer edge of the mouth of the cylindrical structure. Fixing is achieved through a ground electrode connecting screw, a ground electrode fastening nut and a ground electrode cover plate. The cover plate and the ground electrode are connected through the screw and the screw hole and fixed by the ground electrode fastening nut.

[0011] Preferably, the high-voltage electrode is made of a high-temperature resistant conductive material, and the first corundum sheet and the second corundum sheet are made of a ceramic material with high insulation and high thermal stability.

[0012] Preferably, a boss is provided on the first corundum sheet, a number of first side holes are provided around the first corundum sheet, and a first middle hole is provided at the middle position between the first corundum sheet and the boss. An indentation is provided on the second corundum sheet, a number of second side holes are provided around the second corundum sheet, and the boss is arranged in the indentation and their shapes match each other.

[0013] Preferably, the diameter d of the boss ranges from 5 cm < d < 20 cm, with a negative tolerance of no more than 1 mm, and the diameter d of the indentation ranges from 5 cm < d < 20 cm, and has a positive tolerance of no more than 1 mm.

[0014] Preferably, a temperature sensor is provided on the high-voltage electrode to monitor the temperature change of the electrode during operation in real time. There is a spacing between the high-voltage electrode and the boss of the ground electrode, and the gap can be adjusted to meet the electrode gap requirements under different test conditions.

[0015] The beneficial effects of the present invention are as follows:

[0016] 1. The present invention improves the overall high-temperature resistance of the electrodes and can maintain stable performance and reliable connection under long-term high-temperature tests;

[0017] 2. The present invention enhances the vibration resistance of the electrodes and can maintain stable electrical connection during vibration tests;

[0018] 3. The present invention improves the accuracy and reliability of combined aging tests and provides strong support for the reliability assessment of electrical equipment, materials or components. Description of the Drawings

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention.

[0020] Figure 1 An internal structural diagram of the invention;

[0021] Figure 2 for Figure 1 Top view of the first corundum plate in the figure;

[0022] Figure 3 for Figure 1 A cross-sectional view of the first corundum sheet in FIG.

[0023] Figure 4 for Figure 1 Top view of the second corundum plate;

[0024] Figure 5 for Figure 1 Cross-sectional view of the second corundum plate.

[0025] Reference numerals

[0026] In the figure, 1-high voltage electrode; 2-first nut; 3-first corundum sheet, 31-protrusion, 32-first middle hole, 33-first side hole; 4-second corundum sheet, 41-recess, 42-second middle hole, 43-second side hole; 5-cover plate, 6-second nut, 7-screw, 8-insulating oil, 9-boss, 10-pressure plate, 11-insulating sample, 12-spring, 13-ground electrode, 14-equalizing ball. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0028] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0029] Example

[0030] like Figure 1As shown, the present invention provides a high-temperature resistant electric-thermal-vibration combined aging test electrode, including a ground electrode 13 whose inner cavity is sealed by a cover plate 5 on the upper side, the ground electrode 13 is made of electrical copper material or stainless steel material, and the inner cavity is filled with insulating oil 8, and the insulating oil 8 is Kunlun 25# transformer oil. A high-voltage electrode 1 is arranged on the cover plate 5 and the ground electrode 13, and the cover plate 5 and the ground electrode 13 are fixedly connected with the high-voltage electrode 1 through a first nut 2. The lower end of the high-voltage electrode 1 passes through the first corundum sheet 3, the cover plate 5 and the second corundum sheet 4, and is closely attached to the insulating sample 11 through a pressing plate 10. Among them, the first corundum sheet 3, the cover plate 5 and the second corundum sheet 4 play the role of fixing the high-voltage electrode, so that the high-voltage electrode 1 is in close contact with the insulating sample 11. At the same time, the first corundum sheet 3 and the second corundum sheet 4 also play the role of electrically isolating the high-voltage electrode 1 from the cover plate 5, so as to prevent the sleeve structure formed by the high-voltage electrode 1 and the cover plate 5 from surface discharge or air breakdown. Among them, the first corundum sheet 3 and the second corundum sheet 4 cooperate with each other through the boss 31 and the recess 41 respectively provided thereon, fill the air between the high-voltage electrode 1 and the cover plate 5, increase the electrical distance between the high-voltage electrode 1 and the cover plate 5, and the tiny gap between the boss 31 and the recess 41 is filled and cured with potting glue in a vacuum environment to ensure that there are no bubbles therein. Among the preferred technical solutions, a voltage equalizing ball 14 is provided at the top of the high-voltage electrode 1 to equalize the uneven electric field distribution when the high-voltage electrode 1 is connected to an external power supply.

[0031] Preferably, a pressing plate 10 is provided at the lower end of the high voltage electrode 1 for applying high voltage to the insulating sample 11 .

[0032] Preferably, a spring 12 is provided between the lower ends of the high-voltage electrode 1. In this example, the spring 12 is made of a high-temperature resistant elastic alloy. The spring 12 is sleeved on the high-voltage electrode 1 to maintain the stability and contact of the high-voltage electrode 1 under temperature changes and vibration conditions.

[0033] Preferably, a boss 9 is provided at the bottom of the inner cavity of the ground electrode 13 , and the ground electrode 13 and the boss 9 are an integrated structure to form a tighter electrical connection and prevent the insulating oil 8 from invading the gap between the ground electrode 13 and the boss 9 .

[0034] Preferably, the ground electrode 13 is a cylindrical structure, a screw hole is provided at the outer edge of the cylindrical mouth of the cylindrical structure, and the cover plate 5 and the ground electrode 13 are connected through the screw rod 7 and the screw hole and fixed by the ground electrode fastening nut 2.

[0035] Preferably, the high-voltage electrode 1 is made of a high-temperature resistant conductive material, such as electrical copper or constantan or stainless steel, and the first corundum sheet 3 and the second corundum sheet 4 are made of a ceramic material with high insulation and high thermal stability, which serves to electrically isolate the high-voltage electrode 1 from the cover plate 5, thereby preventing the sleeve structure formed by the high-voltage electrode 1 and the cover plate 5 from surface discharge or breakdown of the air.

[0036] As shown Figure 2-5 in the figure, a boss 31 is provided on the first corundum sheet 3. A number of first side holes 33 are provided around the first corundum sheet 3. A first middle hole 32 is provided at the middle position between the first corundum sheet 3 and the boss 31. A concave 41 is provided on the second corundum sheet 4. A number of second side holes 43 are provided around the second corundum sheet 4. The boss 31 is arranged in the concave 41 and their shapes match each other. Preferably, the diameter d of the boss 31 ranges from 5 cm < d < 20 cm and has a negative tolerance of no more than 1 mm. The diameter d of the concave 41 ranges from 5 cm < d < 20 cm and has a positive tolerance of no more than 1 mm. The gap generated when they are assembled is filled with silicone potting adhesive and cured in vacuum, so that the gap is completely filled with the potting adhesive without air bubbles. Among them, the diameter ranges of the boss 31 and the concave 41 are determined by the voltage borne by the device and are related to the breakdown field strength of air. It needs to be designed in combination with specific experiments and the results are obtained through simulation calculation by the finite element method. In this embodiment, the electric field strength at this place in the simulation calculation shall not be higher than 0.3 kV / mm.

[0037] Preferably, a temperature sensor is provided on the high-voltage electrode 1 to monitor the temperature change of the electrode during operation in real time, so as to determine whether the thermal aging temperature of the specimen meets the experimental requirements. There is a spacing between the high-voltage electrode 1 and the boss 9 of the ground electrode 13 and the gap can be adjusted to meet the electrode gap requirements under different test conditions, ensuring that the gap can adapt to insulating specimens 11 of different thicknesses and tightly clamping the insulating specimen 11 in this gap.

[0038] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they learn the basic creative concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0039] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. A high temperature resistant electric-thermal-vibration combined aging test electrode, comprising a ground electrode (13) whose inner cavity is sealed by a cover plate (5) on the upper side, wherein the inner cavity contains insulating oil (8), characterized in that: The cover plate (5) and the ground electrode (13) are fixedly connected to the high-voltage electrode (1) through the first nut (2). The lower end of the high-voltage electrode (1) passes through the first corundum sheet (3), the cover plate (5) and the second corundum sheet (4) and is in close contact with the insulating specimen (11).

2. The high temperature resistant electric-thermal-vibration combined aging test electrode according to claim 1, characterized in that: A grading ball (14) is provided at the top end of the high-voltage electrode (1).

3. The high temperature resistant electric-thermal-vibration combined aging test electrode according to claim 1, characterized in that: A pressure plate (10) is provided at the lower end of the high-voltage electrode (1).

4. The high temperature resistant electric-thermal-vibration combined aging test electrode according to claim 3, characterized in that: A spring (12) is provided between the lower ends of the high-voltage electrodes (1). The spring (12) is made of a high-temperature resistant elastic alloy and is used to maintain the stability and contact of the high-voltage electrode (1) under temperature changes and vibration conditions.

5. The high temperature resistant electric-thermal-vibration combined aging test electrode according to claim 1, characterized in that: A boss (9) is provided at the bottom of the inner cavity of the ground electrode (13), and the ground electrode (13) and the boss (9) are of an integral structure.

6. The high temperature resistant electric-thermal-vibration combined aging test electrode according to claim 1, characterized in that: The ground electrode (13) is of a cylindrical structure. A screw hole is provided on the outer edge of the mouth of the cylindrical structure. The cover plate (5) and the ground electrode (13) are fixed by a screw (7) and a fastening nut (2).

7. The high temperature resistant electric-thermal-vibration combined aging test electrode according to claim 1, characterized in that: The high-voltage electrode (1) is made of a high-temperature resistant conductive material, and the first corundum sheet (3) and the second corundum sheet (4) are made of a ceramic material with high insulation and high thermal stability.

8. The high temperature resistant electric-thermal-vibration combined aging test electrode according to claim 7, characterized in that: A boss (31) is provided on the first corundum sheet (3). A number of first side holes (33) are provided around the first corundum sheet (3). A first middle hole (32) is provided at the middle position between the first corundum sheet (3) and the boss (31). An indentation (41) is provided on the second corundum sheet (4). A number of second side holes (43) are provided around the second corundum sheet (4). The boss (31) is arranged in the indentation (41) and their shapes match each other.

9. The high temperature resistant electric-thermal-vibration combined aging test electrode according to claim 8, characterized in that: The diameter d of the boss (31) ranges from 5 cm < d < 20 cm and has a negative tolerance of no more than 1 mm. The diameter d of the indentation (41) ranges from 5 cm < d < 20 cm and has a positive tolerance of no more than 1 mm.

10. The high temperature resistant electric-thermal-vibration combined aging test electrode according to claim 1, characterized in that: A temperature sensor is provided on the high-voltage electrode (1) for real-time monitoring of the temperature change of the electrode during operation. There is a spacing between the high-voltage electrode (1) and the boss (9) of the ground electrode (13) and the gap can be adjusted to meet the electrode gap requirements under different test conditions.

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