Power frequency withstand voltage detection device for vacuum arc-extinguishing chamber in low-pressure environment

Abstract

The utility model discloses a power frequency withstand voltage detection device for a vacuum arc-extinguishing chamber in a low-pressure environment, which comprises a cylindrical tank body, a working inner cavity, a lower wiring terminal, a tank cover detachably mounted at an opening of the working inner cavity, a three-way air valve, a barometer, a sucking pump and an upper wiring terminal, and a detection assembly comprises at least one group of supporting blocks and a conductive base; the tank body and the tank cover are mutually closed to form a closed working inner cavity between the tank body and the tank cover, and the working inner cavity is used for placing a vacuum arc-extinguishing chamber sample piece to be subjected to withstand voltage detection; the tank cover is provided with an air extracting pump for extracting air, a barometer for detecting air pressure data of the inner side of the working inner cavity, a conductive base and a supporting block, so that the accuracy of a detection environment is ensured, and approximate air pressure corresponding to different altitudes is determined according to an international standard atmosphere meter; the external insulation performance is verified by detecting the power frequency withstand voltage condition of the vacuum arc-extinguishing chamber in the device at low air pressure, so that the environmental adaptability and reliability of the vacuum arc-extinguishing chamber are improved.

Description

Technical Field

[0001] This utility model relates to the field of power frequency withstand voltage testing technology for vacuum interrupters, specifically to a power frequency withstand voltage testing device for vacuum interrupters in low-pressure environments. Background Technology

[0002] External insulation withstand voltage is a crucial manufacturing and testing standard for high-altitude vacuum interrupters, ensuring their safe and reliable operation in such environments. However, the low-pressure environment at high altitudes significantly reduces the external insulation performance of vacuum interrupters, severely impacting their power frequency withstand voltage. Currently, domestic manufacturers of high-altitude vacuum interrupters lack power frequency withstand voltage testing equipment for low-pressure environments, and have not conducted simulated low-pressure power frequency withstand voltage tests during their research and development.

[0003] High-altitude applications impose harsher technical requirements on vacuum interrupters than those for low-altitude ground applications. According to GB311.1, when the altitude is above 1000m, the external insulation withstand voltage of the vacuum interrupter should be the rated withstand voltage multiplied by the coefficient Ka.

[0004] Ka = 1 / (1.1 - H * 0.0001)

[0005] In the formula, H represents the altitude of the location where the product is used (in meters).

[0006] The high-altitude, low-pressure environment of vacuum interrupters leads to a decrease in external insulation performance, severely affecting the power frequency withstand voltage. High-altitude applications place higher demands on the external insulation structure and power frequency withstand voltage strength of vacuum interrupters. Therefore, it is essential to conduct power frequency withstand voltage testing on high-altitude vacuum interrupters by simulating a high-altitude, low-pressure environment. Summary of the Invention

[0007] To address the aforementioned issues, this invention proposes a power frequency withstand voltage testing device for vacuum interrupters in low-pressure environments. This solves the problem in existing technologies where vacuum interrupters that have not undergone low-pressure testing experience experience a significant reduction in external insulation performance in high-altitude, low-pressure environments, severely impacting their power frequency withstand voltage.

[0008] The technical solution adopted by this utility model is: a power frequency withstand voltage testing device for a vacuum interrupter chamber in a low-pressure environment, including a tank body, the tank body being cylindrical, forming an outward-facing working inner cavity, and a lower wiring terminal being provided on the inner side wall of the working inner cavity;

[0009] The can lid is detachably installed at the opening of the working inner cavity, and a sealing gasket is provided at the connection between the two to keep the working inner cavity in a sealed state; and a three-way air valve is provided on the upper end face to communicate with the working inner cavity. The three-way air valve is equipped with an air pressure gauge, an air pump and an upper terminal.

[0010] The detection component includes at least one set of support blocks and a conductive base. The support blocks are placed inside the working cavity, and the upper end face is provided with the conductive base. The conductive base is connected to the lower terminal block by a metal chain.

[0011] Furthermore, the inner bottom wall of the working cavity is provided with a placement groove.

[0012] Furthermore, the sidewall of the support block forms an outward-facing connecting groove.

[0013] Furthermore, the inner wall of the connecting groove, near the edge, is provided with multiple sets of connecting holes.

[0014] Furthermore, it also includes a connecting component, which includes a fixing strap and two sets of connecting protrusions, forming that the connecting protrusions are disposed on one end face of the fixing strap.

[0015] Furthermore, the upper end face of the conductive base is provided with a first fixing hole that runs vertically through it.

[0016] Furthermore, the upper end face of the support block is provided with a second fixing hole that runs vertically through the top and bottom, and the opening direction of the second fixing hole corresponds to that of the first fixing hole.

[0017] Furthermore, the can body is made of a transparent material.

[0018] Furthermore, both the support block and the connecting assembly are made of insulating material.

[0019] Compared with the prior art, this utility model has the following advantages: It uses a tank body and a tank cover that are joined together to form a closed working cavity for placing the vacuum interrupter sample to be tested for withstand pressure. Furthermore, it is equipped with a gas pump on the tank cover, a pressure gauge to monitor the air pressure inside the working cavity, and a conductive base and support block to ensure the accuracy of the testing environment. Based on the international standard atmospheric pressure, it determines the approximate air pressure corresponding to different altitudes. By testing the power frequency withstand voltage of the vacuum interrupter under low air pressure, it verifies the external insulation performance, thereby improving the environmental adaptability and reliability of the vacuum interrupter. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0021] Figure 1 This is an overall structural diagram of the present invention;

[0022] Figure 2 This is a half-sectional view of the overall structure of this utility model;

[0023] Figure 3 This is a half-sectional view of the overall structure of this utility model;

[0024] Figure 4 This is an overall structural diagram of the support block of this utility model;

[0025] Figure 5 for Figure 4 Enlarged view at point A. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0028] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0029] See Figure 1-5This invention discloses a low-pressure environment vacuum interrupter power frequency withstand voltage testing device, comprising a tank body 1 and a tank cover 2. The tank body 1 is cylindrical and made of a transparent material, such as glass or resin (polypropylene), to facilitate observation of the internal testing status. An outward-facing working cavity 100 is formed inside. A lower terminal 8 is provided on the inner wall of the working cavity 100, communicating with the outer side of the working cavity for easy connection to an external power frequency withstand voltage testing platform. The tank cover 2 is detachably installed at the opening of the working cavity 100, and a sealing gasket is provided at the connection point to ensure the working cavity is sealed. A three-way valve 7, communicating with the working cavity 100, is located on the upper surface. The three-way valve 7 includes a pressure gauge 5, a vacuum pump 6, and an upper terminal 80. In use, the vacuum pump 6 evacuates air from the tank body 1, and the pressure gauge 5 detects whether the internal pressure environment has reached the target pressure. Combined with the testing components, the formed testing components include at least one set of support blocks 9 and conductive bases 3. The support blocks 9 are placed inside the working inner cavity 100, and the upper end is provided with the conductive base 3. The conductive base 3 is used to place the vacuum interrupter sample to be tested for withstand voltage. Multiple samples can be placed. If multiple vacuum interrupters are tested simultaneously, they need to be connected in parallel to improve the withstand voltage testing efficiency. The vacuum interrupter 101 to be tested is placed on the conductive base 3. The conductive base 3 and the lower terminal block 8 are connected to each other by a metal chain 11. The moving rod of the vacuum interrupter 101 placed on the conductive base 3 is connected to the upper terminal block 80 by a metal chain. The upper and lower terminals are connected to the power frequency withstand voltage testing station for withstand voltage testing. After the test is completed, the three-way air valve 7 is opened to restore the gas pressure inside the tank. The tank cover 2 is opened and the vacuum interrupter is taken out.

[0030] Specifically, to ensure the stability of the built-in support block 9 when it works inside its working cavity, a placement groove 100 is provided on the bottom wall of the inner side of its working cavity 100, and the inner side of the placement groove 100 is used to place the support block 9.

[0031] During use, when the height of the conductive base needs to be adjusted, the height can be adjusted by increasing or decreasing the number of support blocks 9. If multiple sets of support blocks 9 are stacked on top of each other, in order to ensure stability, the sidewall of the formed support block 9 forms an outward-facing connecting groove 91; and the inner wall of the connecting groove 91, near the edge, is provided with multiple sets of connecting holes 901.

[0032] A connecting assembly is then provided, comprising a fixing band 92 and two sets of connecting protrusions 902. The connecting protrusions 902 are positioned on one end face of the fixing band 92. The connecting protrusions 902 on the fixing band 92 are inserted into the connecting holes 901 formed on the sidewalls of two adjacent support blocks 9. The resulting connecting grooves 91 can be on one sidewall, on opposite sidewalls, or on each sidewall, to cooperate with the connecting assembly and achieve stability between the two sets of superimposed support blocks 9. In actual manufacturing, setting them on opposite sidewalls ensures connection stability while reducing processing costs. Both the support blocks 9 and the connecting assembly are made of insulating materials, such as polytetrafluoroethylene (PTFE): possessing extremely high resistivity (up to 10^18 Ω·cm), low dielectric loss, high dielectric strength (1000 volts / mil), and temperature stability (-200°C to 260°C), it is one of the best known electrical insulation materials. It is commonly used in high-frequency circuits and cable insulation. Polyethylene (PE) and polyvinyl chloride (PVC): widely used in wire and cable sheathing and electronic component insulation. Polyetheretherketone (PEEK): high temperature resistance (long-term 260°C), high mechanical strength, and maintains excellent insulation under high pressure and high humidity environments. Also made of materials such as polypropylene. The conductive base 3, which holds the vacuum interrupter sample to be tested for withstand voltage, is in direct contact with the tank body, causing leakage and affecting the accuracy of the test.

[0033] Specifically, the upper end face of the conductive base 3 is provided with a first fixing hole 30 that extends vertically, and the upper end face of the support block 9 is provided with a second fixing hole 90 that extends vertically. The opening direction of the second fixing hole 90 corresponds to that of the first fixing hole 30. In actual manufacturing, the first fixing hole 30 and the second fixing hole 90 can be provided with threaded holes and external bolts to fix the conductive base 3 to the support block 9, and can also be disassembled for easy replacement.

[0034] In addition to the preferred embodiments described above, there are other embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection claimed by this utility model.

Claims

1. A power frequency withstand voltage testing device for a vacuum interrupter in a low-pressure environment, characterized in that, include: The tank (1) is columnar and has an outward-facing working cavity (10) inside. The inner side wall of the working cavity (10) is provided with a lower wiring terminal (8). The can lid (2) is detachably installed at the opening of the working inner cavity (10), and a sealing gasket is provided at the connection between the two to make the working inner cavity formed therein in a sealed state; and a three-way air valve (7) is provided on the upper end face to communicate with the working inner cavity (10). The three-way air valve (7) is provided with a pressure gauge (5), an air pump (6), and an upper terminal (80). The detection component includes at least one set of support blocks (9) and a conductive base (3). The support blocks (9) are placed inside the working cavity (10) and the conductive base (3) is provided on the upper end face. The conductive base (3) is connected to the lower terminal (8) by a metal chain (11).

2. The low-pressure environment vacuum interrupter chamber power frequency withstand voltage testing device according to claim 1, characterized in that, The inner bottom wall of the working cavity (10) is provided with a placement groove (100).

3. The low-pressure environment vacuum interrupter power frequency withstand voltage testing device according to claim 2, characterized in that, The sidewall of the support block (9) forms an outward-facing connecting groove (91).

4. The low-pressure environment vacuum interrupter power frequency withstand voltage testing device according to claim 3, characterized in that, The inner wall of the connecting groove (91) is provided with multiple sets of connecting holes (901) near the edge.

5. The low-pressure environment vacuum interrupter power frequency withstand voltage testing device according to claim 4, characterized in that, It also includes a connecting component, which includes a fixing band (92) and two sets of connecting protrusions (902), forming that the connecting protrusions (902) are disposed on one end face of the fixing band (92).

6. The low-pressure environment vacuum interrupter power frequency withstand voltage testing device according to claim 5, characterized in that, The conductive base (3) has a first fixing hole (30) that runs vertically through the upper end face.

7. The low-pressure environment vacuum interrupter power frequency withstand voltage testing device according to claim 6, characterized in that, The upper end face of the support block (9) is provided with a second fixing hole (90) that runs through the top and bottom, and the opening direction of the second fixing hole (90) corresponds to that of the first fixing hole (30).

8. The low-pressure environment vacuum interrupter power frequency withstand voltage testing device according to claim 7, characterized in that, The tank (1) is made of transparent material.

9. The low-pressure environment vacuum interrupter power frequency withstand voltage testing device according to claim 8, characterized in that, Both the support block (9) and the connecting component are made of insulating material.

Images