A spark gap shielding device and mounting structure

Abstract

The application provides a spark gap shielding device and mounting structure, comprising: a plurality of shielding ring bodies and support rods; wherein each of the shielding ring bodies is distributed along the circumference of a shell of a spark gap to be shielded, and the shape of a shielding assembly composed of each of the shielding ring bodies matches the shape of the shell of the spark gap to be shielded; and each of the shielding ring bodies is connected with a plurality of support rods on the side close to the shell of the spark gap to be shielded, so as to be connected with the shell of the spark gap to be shielded. In the application, a plurality of shielding ring bodies are distributed along the circumference of the shell of the spark gap to be shielded, and the connection between each of the shielding ring bodies and the shell of the spark gap to be shielded is realized through the support rods, so that the corona can be effectively prevented, the electric field intensity on the shell of the spark gap and the stray capacitance between the shell and the adjacent equipment can be reduced, and the influence of the stray capacitance on the spark gap control system is reduced.

Description

Technical Field

[0001] This invention relates to the field of power technology, and more specifically, to a spark gap shielding device and its installation structure. Background Technology

[0002] Currently, the overvoltage protection of ultra-high voltage and extra-high voltage series compensation devices in China usually adopts the working mode of metal oxide voltage limiter (MOV) and spark gap. Among them, MOV is the main protection of capacitor bank, and spark gap is the main protection of MOV and the backup protection of capacitor bank.

[0003] When a short circuit or ground fault occurs in the line, and the energy absorbed by the MOV reaches a set value, the series compensation control and protection system issues a trigger command to force the spark gap to discharge and conduct, thus protecting the MOV and capacitor bank. The use of a spark gap allows for a significant reduction in the MOV capacity in the series compensation device, lowering the investment in series compensation projects and greatly improving the safety and reliability of the system.

[0004] The spark gap consists of two pairs of electrodes connected in series, with each pair forming a discharge gap. A capacitor is connected in parallel between the two gaps to equalize the voltage.

[0005] The spark gap is housed within a semi-enclosed gap housing. This housing has sharp corners, which can generate corona discharge. Furthermore, the gap housing is typically large, and stray capacitance exists between it and nearby equipment, potentially affecting the normal operation of the spark gap control system. Summary of the Invention

[0006] In view of this, the present invention proposes a spark gap shielding device and installation structure, which aims to solve the problems of existing spark gap housings being prone to corona discharge and stray capacitance with adjacent equipment. In one aspect, the present invention provides a spark gap shielding device, comprising: a plurality of shielding ring bodies and a support rod; wherein, Each of the shielding ring bodies is distributed circumferentially along the outer shell of the spark gap to be shielded, and the shape of the shielding assembly composed of each of the shielding ring bodies matches the shape of the outer shell of the spark gap to be shielded. Each of the shielding ring bodies has several support rods connected to the side of the outer shell of the spark gap to be shielded, for connecting to the outer shell of the spark gap to be shielded.

[0007] Furthermore, in the above-mentioned spark gap shielding device, the shielding ring body includes a first segment and a second segment connected to each other, the extension lines of the first segment and the second segment forming a preset angle; and the ends of the first segment and the second segment that are far apart from each other are hemispherical.

[0008] Furthermore, in the above-mentioned spark gap shielding device, the preset included angle is an obtuse angle.

[0009] Furthermore, in the above-mentioned spark gap shielding device, the connection between the first segment and the second segment is a transition arc.

[0010] Furthermore, in the above-mentioned spark gap shielding device, the radius of the transition arc is greater than or equal to 50mm.

[0011] Furthermore, in the above-mentioned spark gap shielding device, the shielding ring body is arc-shaped.

[0012] Furthermore, in the above-mentioned spark gap shielding device, the shielding ring body is made of hollow aluminum tube; and / or the support rod is made of hollow aluminum tube.

[0013] The spark gap shielding device of the present invention effectively prevents corona generation and reduces the electric field strength on the spark gap shell and stray capacitance with adjacent equipment by distributing multiple shielding ring bodies circumferentially on the spark gap shell and connecting each shielding ring body to the spark gap shell through a support rod. This reduces the impact of stray capacitance on the spark gap control system.

[0014] The present invention also provides an installation structure for a spark gap shielding device, comprising: a spark gap housing to be shielded and a plurality of spark gap shielding devices as described in any one of the preceding claims; wherein, Each of the spark gap shielding devices is respectively disposed on the top and / or bottom of the outer shell of the spark gap to be shielded, and there is a preset insulation distance between two spark gap shielding devices that are close to each other on adjacent spark gaps to be shielded.

[0015] Furthermore, in the installation structure of the above-mentioned spark gap shielding device, the minimum insulation distance between two spark gap shielding devices that are close to each other between adjacent spark gap shells with power frequency withstand voltage less than or equal to 280kV is greater than or equal to 630mm.

[0016] Furthermore, in the installation structure of the above-mentioned spark gap shielding device, the minimum insulation distance between two adjacent spark gap shielding devices with power frequency withstand voltages greater than 280kV and less than or equal to 410kV is greater than or equal to 900mm.

[0017] This invention effectively prevents corona generation and reduces the electric field strength on the spark gap housing and stray capacitance with adjacent equipment by installing one or more sets of spark gap shielding devices on the spark gap housing and ensuring the insulation distance between the spark gap shielding devices that are close to each other. This reduces the impact of stray capacitance on the spark gap control system. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a schematic diagram of the spark gap shielding device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the shielding body in the spark gap shielding device provided in an embodiment of the present invention; Figure 3 This is a top view of the installation structure of the spark gap shielding device provided in an embodiment of the present invention. Detailed Implementation

[0019] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] See Figure 1 and Figure 2 The spark gap shielding device of this invention includes: a plurality of shielding ring bodies 1 and support rods 2; wherein, each of the shielding ring bodies 1 is distributed circumferentially along the outer shell 3 of the spark gap to be shielded, and the shape of the shielding assembly composed of each of the shielding ring bodies 1 matches the shape of the outer shell 3 of the spark gap to be shielded; each of the shielding ring bodies 1 is connected to a plurality of support rods 2 on the side near the outer shell 3 of the spark gap to be shielded, for connecting with the outer shell 3 of the spark gap to be shielded.

[0021] Specifically, each shielding ring body 1 can be distributed along the entire circumference of the spark gap shell 3 to be shielded, or only a portion of the shielding ring body 1 can be arranged in the circumferential direction of the spark gap shell 3 to be shielded, so as to form a shielding area around the spark gap shell 3 to be shielded.

[0022] The shielding ring body 1 is made of metal, preferably a hollow aluminum tube. Since the shielding ring body 1 and the outer shell 3 of the spark gap to be shielded are equipotentially connected, the support rod 2 is preferably made of metal, eliminating the need for additional leads and making connection more convenient. The fact that both the shielding ring body 1 and the support rod 2 are made of hollow aluminum tubes reduces the overall weight of the device. In this embodiment, the diameter of the hollow aluminum tube used to prepare the shielding ring body 1 and the support rod 2 can be greater than 50 mm.

[0023] In one specific embodiment of this invention, the shielding ring body 1 includes a first segment 11 and a second segment 12 connected to each other, with the extension lines of the first segment 11 and the second segment 12 forming a preset angle; and the ends of the first segment 11 and the second segment 12 that are far apart from each other are hemispherical. The preset angle can be an obtuse angle, such as 120°, 135°, 160°, etc., preferably 135°.

[0024] In order to better equalize the electric field around the spark gap and reduce the generation of corona, the connection between the first segment and the second segment is a transition arc α. At this time, the shielding assembly composed of each shielding ring body 1 is a polygon-like structure.

[0025] Preferably, the radius of the transition arc α is greater than or equal to 50 mm.

[0026] In another embodiment of this invention, the shielding ring body 1 is arc-shaped. The shielding assembly composed of the shielding ring bodies 1 is circular in shape.

[0027] In this embodiment, each shielding ring body 1 is provided with one or more support rods 2. The support rods 2 are welded to the shielding ring body 1. The cross-section of the support rod 2 can be a rectangular structure, for example, a rectangular tube with a relatively flat opening. When there is one support rod 2, it can be set at the connection between the first segment 11 and the second segment 12 of the shielding ring body 1. Preferably, there are two support rods 2, and the two support rods 2 are respectively connected to both ends of the shielding ring body 1. The support rod 2 is provided with a connecting hole, which can be connected to the mounting hole on the spark gap housing 3 to be shielded by a connector. For example, it can be connected to the spark gap housing 3 to be shielded by bolts.

[0028] It is evident from the above that the spark gap shielding device provided in this embodiment, by distributing multiple shielding ring bodies circumferentially on the spark gap shell to be shielded and connecting each shielding ring body to the spark gap shell to be shielded through a support rod, can effectively prevent corona generation and reduce the electric field strength on the spark gap shell and stray capacitance with adjacent equipment, thereby reducing the impact of stray capacitance on the spark gap control system.

[0029] See Figure 1 and Figure 3 The present invention also provides an installation structure for a spark gap shielding device, comprising: a spark gap housing 3 to be shielded and a plurality of the above-mentioned spark gap shielding devices; wherein each of the spark gap shielding devices is respectively disposed on the top and / or bottom of the spark gap housing 3 to be shielded, and there is a preset insulation distance d between two spark gap shielding devices that are close to each other on adjacent spark gaps to be shielded.

[0030] Specifically, the shielding device can be installed on different types of spark gap housing 3 to be shielded. The shielding device can be installed only on the top or bottom of the spark gap housing 3 to be shielded, or the shielding device can be installed on both the top and bottom of the spark gap housing 3 to be shielded.

[0031] The top and bottom of the spark gap housing 3 to be shielded may also be provided with clamping members to clamp the support rod of the shielding device, thereby facilitating the secure installation of the shielding device on the housing of the spark gap to be shielded. The clamping member may include: a transverse fixing member and a snap-fit ​​part provided at both ends of the transverse fixing member. The snap-fit ​​part may be a metal plate that can be inserted into the tail end of the support rod 2 to further ensure a reliable connection between the support rod 2 and the housing of the spark gap to be shielded.

[0032] Taking a spark gap with a double-gap housing installed in series as an example, one or more sets of shielding devices can be installed on the mounting holes at the top and bottom of the upper gap housing 31 and the lower gap housing 32 of the spark gap. For example, a maximum of 4 sets of shielding devices can be installed at the top and bottom of the upper gap housing and the lower gap housing, with 4 shielding ring bodies 1 in each set. Alternatively, fewer sets of shielding devices or fewer shielding ring bodies 1 can be installed.

[0033] The insulation distance between the shielding device and the adjacent gap housing should meet the requirements of the spark gap insulation level. Therefore, in this embodiment, different insulation distances are used for the spark gap housing 3 to be shielded with a power frequency withstand voltage of less than or equal to 280kV and the spark gap housing 3 to be shielded with a power frequency withstand voltage of greater than 280kV and less than or equal to 410kV.

[0034] The minimum insulation distance between two adjacent spark gap shielding devices with power frequency withstand voltage less than or equal to 280kV and close to each other is greater than or equal to 630mm.

[0035] The minimum insulation distance between two adjacent spark gap shielding devices with power frequency withstand voltages greater than 280kV and less than or equal to 410kV is greater than or equal to 900mm.

[0036] The relevant aspects of the installation structure embodiment and the above-described device embodiment can be referred to each other, and will not be repeated here.

[0037] In summary, by installing one or more sets of spark gap shielding devices on the spark gap housing and ensuring the insulation distance between the spark gap shielding devices that are close to each other, the present invention can effectively prevent corona generation and reduce the electric field strength on the spark gap housing and stray capacitance between the spark gap housing and adjacent equipment, thereby reducing the impact of stray capacitance on the spark gap control system.

[0038] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A spark gap shielding device, characterized in that, include: Several shielding ring bodies and support rods; among them, Each of the shielding ring bodies is distributed circumferentially along the outer shell of the spark gap to be shielded, and the shielding ring bodies together form a shield. The shape of the shielding component matches the shape of the housing of the spark gap to be shielded; Each of the shielding ring bodies has several support rods connected to the side near the outer shell of the spark gap to be shielded, for use in... It is connected to the outer shell of the spark gap to be shielded; there are two support rods, which are respectively connected to both ends of the shielding ring body; The shielding ring body includes a first segment and a second segment connected to each other, with the extension lines of the first segment and the second segment forming a 135° angle; and the ends of the first segment and the second segment that are far apart from each other are hemispherical; the connection between the first segment and the second segment is a transition arc; the radius of the transition arc is greater than or equal to 50 mm.

2. The spark gap shielding device according to claim 1, characterized in that, The shielding ring body is arc-shaped.

3. The spark gap shielding device according to claim 1, characterized in that, The shielding ring body is made of hollow aluminum. The support rod is made of tubing; and / or the support rod is made of hollow aluminum tubing.

4. An installation structure for a spark gap shielding device, characterized in that, include: The outer shell of the spark gap to be shielded and several Spark gap shielding device as described in any one of claims 1 to 3; wherein, Each of the spark gap shielding devices is respectively disposed on the top and / or bottom of the outer shell of the spark gap to be shielded, and there is a preset insulation distance between two spark gap shielding devices that are close to each other on adjacent spark gaps to be shielded.

5. The installation structure of the spark gap shielding device according to claim 4, characterized in that, Adjacent power frequency withstand Two spark gap shielding devices with a voltage of 280kV or less, located close to each other, are used to shield the spark gap housings of the two devices. The minimum insulation distance is greater than or equal to 630mm.

6. The installation structure of the spark gap shielding device according to claim 4, characterized in that, Adjacent power frequency withstand The minimum insulation distance between two close-proximity spark gap shielding devices between the shells of the spark gap to be shielded, subject to a voltage greater than 280kV and less than or equal to 410kV, is greater than or equal to 900mm.

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