Insulation experiment device for 35-kilovolt plug-in bushing transformer

Abstract

The utility model provides an insulation experiment device for a 35-kilovolt plug-in bushing transformer, a bushing seat is arranged at the bottom of the insulation experiment device, the bushing seat is vertically and fixedly arranged on the surface of a fixed seat in a penetrating manner, an organic glass insulation cylinder is arranged on the outer side of the upper part of the bushing seat, a sealing gasket is arranged between the bushing seat and the organic glass insulation cylinder, and the upper part of the organic glass insulation cylinder is provided with a sealing ring. An oil drain plug is arranged at the bottom of the organic glass insulating cylinder, and a conducting rod is vertically arranged in the center of the interior of the organic glass insulating cylinder to replace a conventional separable plug test terminal with a cable. The problems that the separable plugging head and the sleeve seat are damaged due to electrical breakdown and even the transformer is damaged due to the problems of installation omission or non-standardization, the plugging service life of the plugging head and the like during the insulation test of the transformer are effectively avoided, the test cost is reduced, and the test efficiency is improved.

Description

Technical Field

[0001] This article belongs to the technical field of transformer insulation experiments, and specifically relates to an insulation experiment device for a 35 kV plug-in type bushing transformer Background Technique

[0002] For a plug-in type bushing transformer below 35 kV, the high-voltage side is connected to the bushing socket 9 on the transformer body through a separable plug. One end of the bushing socket 9 is immersed in the transformer oil and connected to the transformer, and the other end of the bushing socket 9 is placed in the air and connected to the separable plug. The separable plug is generally made of ethylene propylene diene monomer (EPDM), and the bushing socket is generally made of epoxy insulating material. The size of the plug interface matches the size of the right-side interface of the bushing socket, and the plug and the bushing socket are tightly connected by bolts, so that the high-voltage side cable is connected to the transformer to form a power supply loop. Compared with conventional air bushings, this connection method has the advantages of full insulation, full sealing, separable, and touchable under live conditions. The disadvantages are that the plug and the bushing socket are for special connection, all accessories need to be used in a matching manner, and they belong to an integrated whole that cooperates with each other. Moreover, the installation and cable production requirements are relatively high, and electrical accidents are often caused by non-standard installation. At the same time, the plug and unplug life of the separable plug is relatively short, and the cost is relatively high

[0003] According to national standards, after the production and manufacture of a transformer are completed, high-voltage insulation tests need to be carried out to verify the insulation performance of the transformer, such as external applied voltage tests, induced voltage tests, lightning impulse tests, etc

[0004] For a plug-in type bushing transformer below 35 kV, the bushing socket on the transformer body and the separable plug need to be reliably connected to ensure the insulation performance. Therefore, when conducting an insulation test on the transformer, due to the insufficient insulation strength of the bushing socket's own structure, the test voltage cannot be directly applied to the bushing socket. The conventional method is to prefabricate a set of separable plugs with cables as test terminals. During the test, the prefabricated separable plug test terminal is connected to the bushing socket and connected to the test power supply through a cable to conduct a high-voltage insulation test on the transformer. During the high-voltage insulation test process, due to the high test voltage, electrical breakdown and damage of the separable plug and the bushing socket often occur due to installation omissions or non-standardization, the plug and unplug life of the plug, etc., and even damage to the transformer. The electrical breakdown and damage of the separable plug and the bushing socket are irreparable, and new separable plugs and bushing sockets must be replaced, resulting in relatively high replacement costs and seriously affecting the test efficiency Content of the Utility Model

[0005] To solve the above problems, this paper proposes an insulation experiment device for a 35 kV plug-and-play bushing transformer. The bottom of the insulation experiment device is provided with a bushing seat, and the bushing seat is vertically and fixedly arranged through the surface of the fixed seat. An organic glass insulating cylinder is arranged on the outer side of the upper part of the bushing seat, and a gasket is arranged between the bushing seat and the organic glass insulating cylinder. An oil drain plug is arranged at the bottom of the organic glass insulating cylinder, and a conducting rod is vertically and fixedly arranged at the center of the inside of the organic glass insulating cylinder. Threads are arranged on the outer sides of both ends of the conducting rod, the lower end of the conducting rod is threadedly connected to the top surface of the bushing seat, and an insulating pressing block is arranged through the outer side of the upper end of the conducting rod. The inside of the organic glass insulating cylinder is filled with transformer insulating oil, replacing the conventional separable plug test terminal with a cable, effectively avoiding the problem of electrical breakdown and damage between the separable plug and the bushing seat caused by installation omissions or non-standardization, the plugging and unplugging life of the plug, etc. during the transformer insulation test, and even causing damage to the transformer, reducing the test cost, and improving the test efficiency.

[0006] The shape of the bushing seat is a double-ended symmetric cone-shaped shuttle seat. An assembly edge is annularly arranged on the outer side of the middle of the bushing seat, and a sleeve hole is vertically penetrated through the center of the bushing seat. Assembly threads are arranged at both ends of the inner side of the sleeve hole. The bushing seat is nested on the surface of the fixed seat in a snap-fit manner through the assembly edge, and a gasket is sleeved on the outer side of the upper end of the assembly edge of the bushing seat. By using a universal bushing seat, it can be adapted to the existing energizing device, so as to conduct experiments conveniently.

[0007] The shape of the organic glass insulating cylinder is a cylindrical cylinder. An oil drain plug is arranged on the outer side of the bottom of the organic glass insulating cylinder, and a gasket is sleeved on the outer side of the bottom of the organic glass insulating cylinder. An insulating pressing block is arranged across the top of the organic glass insulating cylinder. Through the organic glass insulating cylinder, the change of the internal transformer insulating oil during the experiment can be clearly observed, so as to judge the actual insulation effect.

[0008] The shape of the conducting rod is cylindrical. Threads are symmetrically arranged at both the upper and lower ends of the conducting rod. An insulating pressing block is arranged through the outer side of the upper end of the conducting rod. A pressing flat pad is arranged on the upper surface of the insulating pressing block, and a pressing nut is arranged above the pressing flat pad. The pressing nut is connected to the outer side of the upper end of the conducting rod through threads, and the outer side of the bottom end of the conducting rod is connected to the inside of the bushing seat through threads. By arranging threads at both ends of the conducting rod, it is convenient to install and fix the conducting rod, so that it can be vertically and parallelly arranged inside the mailing glass insulating cylinder without contacting its outer wall.

[0009] The gasket is a socket - type gasket. A number of locking bolts are equidistantly arranged in a circular pattern on the outer side of the gasket. The inner side of the gasket is hermetically connected to the outer side of the upper end of the bushing seat and the bottom end of the plexiglass insulating cylinder. Through the gasket, the sealed placement of the transformer insulating oil between the conductive rod and the bushing seat can be ensured, enabling it to meet the requirements of insulation experiments.

[0010] The insulating pressing block is in the shape of a rectangular block. A through - hole is provided in a penetrating manner at the center of the insulating pressing block. The length of the insulating pressing block is greater than the outer diameter of the plexiglass insulating cylinder, and the diameter of the through - hole of the insulating pressing block is greater than the diameter of the conductive rod. Through the insulating pressing block, the conductive rod can be stably fixed without contacting the plexiglass insulating cylinder, thus realizing the stability of the experiment.

[0011] Beneficial effects:

[0012] It can meet high - voltage insulation tests such as external application withstand voltage tests, induced voltage tests, lightning impulse tests, etc. It can be reused infinitely, is convenient for disassembly and assembly, has a low cost, and effectively avoids problems such as electrical breakdown and damage of the separable plug - in head and the bushing seat caused by installation omissions or non - standardization, the plug - in and unplugging life of the plug - in head during the transformer insulation test, and even problems such as damage to the transformer. It reduces the test cost and improves the test efficiency. Description of the drawings

[0013] Figure 1 It is a schematic diagram of an insulation test device for a 35 - kV plug - in type bushing transformer;

[0014] Figure 2 It is an internal schematic diagram of an insulation test device for a 35 - kV plug - in type bushing transformer;

[0015] In the figure: 1. Conductive rod, 2. Compression flat gasket, 3. Compression nut, 4. Insulating pressing block, 5. Plexiglass insulating cylinder, 6. Transformer insulating oil, 7. Gasket, 8. Oil drain plug, 9. Bushing seat. Detailed implementation manners

[0016] To deepen the understanding of the present utility model, the present utility model will be further described in detail below in combination with embodiments and drawings. This embodiment is only used to explain the present utility model and does not constitute a limitation on the protection scope of the present utility model.

[0017] Conductive rod 1, compression flat gasket 2, compression nut 3, insulating pressing block 4, plexiglass insulating cylinder 5, transformer insulating oil 6, gasket 7, oil drain plug 8, bushing seat 9.

[0018] As Figure 1 、 2 shown;

[0019] An insulation experiment device for a 35 kV plug-in bushing transformer. The bottom of the insulation experiment device is provided with a bushing seat 9. The bushing seat 9 is vertically and fixedly arranged in a penetrating manner on the surface of the fixed seat. An organic glass insulation cylinder 5 is arranged on the outer side of the upper part of the bushing seat 9. A sealing gasket 7 is arranged between the bushing seat 9 and the organic glass insulation cylinder 5. An oil drain plug 8 is arranged at the bottom of the organic glass insulation cylinder 5. A conductive rod 1 is vertically and fixedly arranged at the center inside the organic glass insulation cylinder 5. Threads are arranged on the outer sides of both ends of the conductive rod 1. The lower end of the conductive rod 1 is threadedly connected to the top surface of the bushing seat 9. An insulation pressing block 4 is arranged in a penetrating manner on the outer side of the upper end of the conductive rod 1. The inside of the organic glass insulation cylinder 5 is filled with transformer insulating oil 6. The shape of the bushing seat 9 is a double-ended symmetric conical spindle-shaped socket. An assembly edge is annularly arranged on the outer side of the middle part of the bushing seat 9. A socket hole is vertically penetrated through the center of the bushing seat 9. Assembly threads are arranged at both inner ends of the socket hole. The bushing seat 9 is nested on the surface of the fixed seat in a clamping manner through the assembly edge. A sealing gasket 7 is sleeved on the outer side of the upper end of the assembly edge of the bushing seat 9. The shape of the organic glass insulation cylinder 5 is a cylindrical cylinder. An oil drain plug 8 is arranged on the outer side of the bottom of the organic glass insulation cylinder 5. A sealing gasket 7 is sleeved on the outer side of the bottom of the organic glass insulation cylinder 5. An insulation pressing block 4 is arranged in a spanning manner at the top end of the organic glass insulation cylinder 5. The shape of the conductive rod 1 is cylindrical. Threads are symmetrically arranged at both the upper and lower ends of the conductive rod 1. An insulation pressing block 4 is arranged in a penetrating manner on the outer side of the upper end of the conductive rod 1. A pressing flat gasket 2 is arranged on the upper surface of the insulation pressing block 4. A pressing nut 3 is arranged above the pressing flat gasket 2. The pressing nut 3 is connected to the outer side of the upper end of the conductive rod 1 through threads. The outer side of the bottom end of the conductive rod 1 is connected to the inside of the bushing seat 9 through threads. The sealing gasket 7 is a sleeved sealing gasket 7. A number of locking bolts are annularly and equidistantly arranged on the outer side of the sealing gasket 7. The inner side of the sealing gasket 7 is hermetically connected to the outer side of the upper end of the bushing seat 9 and the bottom end of the organic glass insulation cylinder 5. The shape of the insulation pressing block is a rectangular block. A through hole is penetrated through the center of the insulation pressing block. The length of the insulation pressing block is greater than the outer diameter of the organic glass insulation cylinder 5. The diameter of the through hole of the insulation pressing block is greater than the diameter of the conductive rod 1.

[0020] Implementation example;

[0021] Before conducting the high-voltage insulation test of the transformer, first connect the external thread at one end of the conductive rod 1 to the internal thread of the bushing seat 9. Then, place the sealing gasket 7 on the bushing seat 9 in sequence. After that, place the plexiglass insulating cylinder 5 on the sealing gasket 7. Next, pass the insulating pressing block 4 through the conductive rod 1 and press it on the upper part of the plexiglass insulating cylinder 5. Then, install the pressing flat gasket 2 and the pressing nut 3 on the thread on the other side of the conductive rod 1 for tightening and locking. Finally, inject a certain amount of transformer insulating oil 6 into the plexiglass insulating cylinder 5. When conducting the high-voltage insulation test of the transformer, apply the test power supply to the upper end of the conductive rod 1, and transfer the test voltage to the bushing seat 9 through the conductive rod 1, and finally transfer it to the transformer. Since the plexiglass insulating cylinder 5 is filled with transformer insulating oil 6, the air insulation on one side of the bushing seat 9 is changed to an oil insulation structure, which can directly withstand the high-voltage insulation test of the transformer. After the high-voltage insulation test of the transformer is completed, drain the injected transformer insulating oil 6 through the oil drain plug 8 at the lower part of the plexiglass insulating cylinder 5, then remove each component in sequence, and then install the test device on another transformer for the high-voltage insulation test.

[0022] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An insulation test device for a 35 kV pluggable bushing transformer, wherein a bushing seat is provided at the bottom of the insulation test device, characterized in that: The bushing seat is vertically fixed and penetrated on the surface of the fixing seat, an organic glass insulating tube is provided on the outer side of the upper part of the bushing seat, a sealing gasket is provided between the bushing seat and the organic glass insulating tube, an oil drain plug is provided at the bottom of the organic glass insulating tube, a conductive rod is vertically provided at the inner center of the organic glass insulating tube, threads are provided on the outer sides of both ends of the conductive rod, the lower end of the conductive rod is threadedly connected to the top surface of the bushing seat, an insulating pressure block is penetrated on the outer side of the upper end of the conductive rod, and the interior of the organic glass insulating tube is filled with transformer insulating oil.

2. The insulation test device for a 35 kV pluggable bushing transformer according to claim 1 is characterized in that: The shape of the sleeve seat is a double-ended symmetrical conical shuttle-shaped sleeve, a mounting edge is provided in a ring shape on the outer middle part of the sleeve seat, a sleeve hole is provided vertically through the center of the sleeve seat, both ends of the inner side of the sleeve hole are provided with mounting threads, the sleeve seat is nested in the surface of the fixed seat through the mounting edge, and a sealing gasket is provided on the outer upper end of the mounting edge of the sleeve seat.

3. The insulation test device for a 35 kV pluggable bushing transformer according to claim 1, characterized in that: The plexiglass insulating cylinder is in the shape of a cylindrical cylinder, an oil drain plug is arranged on the outer side of the bottom of the plexiglass insulating cylinder, a sealing gasket is sleeved on the outer side of the bottom of the plexiglass insulating cylinder, and an insulating pressing block is arranged across the top of the plexiglass insulating cylinder.

4. The insulation test device for a 35 kV pluggable bushing transformer according to claim 1, characterized in that: The conductive rod is cylindrical in shape, and threads are symmetrically arranged at the upper and lower ends of the conductive rod. An insulating pressure block is penetrated through the outer side of the upper end of the conductive rod. A clamping flat pad is arranged on the upper surface of the insulating pressure block. A clamping nut is arranged above the clamping flat pad. The clamping nut is connected to the outer side of the upper end of the conductive rod through threads, and the outer side of the bottom end of the conductive rod is connected to the inside of the sleeve seat through threads.

5. The insulation test device for a 35 kV pluggable bushing transformer according to claim 1, characterized in that: The sealing gasket is a sleeve-type sealing gasket, and a plurality of locking bolts are equidistantly arranged in an annular manner on the outer side of the sealing gasket, and the inner side of the sealing gasket is sealed and connected with the outer side of the upper end of the sleeve seat and the bottom end of the organic glass insulating tube.

6. The insulation test device for a 35 kV pluggable bushing transformer according to claim 1, characterized in that: The insulating block is in the shape of a rectangular block, a through hole is provided in the center of the insulating block, the length of the insulating block is greater than the outer diameter of the organic glass insulating cylinder, and the diameter of the through hole of the insulating block is greater than the diameter of the conductive rod.

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