An ultra-high voltage arrester

Abstract

The application discloses a kind of extra-high voltage lightning arrester, including multiple lightning arrester elements of series stacking, the lightning arrester element at top is provided with first wiring terminal, the lightning arrester element at bottom is provided with second wiring terminal;The second wiring terminal is led out by the side of the connecting flange of the lower end of the lightning arrester element at bottom, and is insulated from the connecting flange, the second wiring terminal is used for electrical connection with monitoring device and ground terminal;The lightning arrester element includes composite outer sleeve and resistance disc column arranged inside the composite outer sleeve, the lightning arrester element is provided with first end cover at both ends, and the outer diameter of the composite outer sleeve of the lightning arrester element at bottom is greater than the outer diameter of the composite outer sleeve of the lightning arrester element at top.The application can be suitable for high altitude, high seismic intensity and high pollution grade area, with strong anti-seismic ability, high mechanical strength and light weight.

Description

Technical Field

[0001] This invention relates to the field of surge arrester technology, and more particularly to an ultra-high voltage surge arrester. Background Technology

[0002] Currently, energy reserves and electricity load distribution are extremely uneven. Developing ultra-high voltage (UHV) power transmission is an inevitable choice for optimizing energy allocation and an important measure for building a new power system. Surge arresters are the foundation of insulation coordination, an important means of suppressing overvoltage, and a key piece of equipment for protecting UHV systems.

[0003] The development of water, wind, and solar resources, along with the construction of clean energy power plants, has driven the construction of ultra-high voltage (UHV) power transmission projects. Building UHV substations in high-altitude, high-seismic-intensity areas places high demands on the insulation and seismic resistance of electrical equipment, increasing the difficulty of equipment manufacturing, especially for UHV surge arresters with a height-to-diameter ratio exceeding 14 meters.

[0004] Currently, the seismic resistance and external insulation level of ultra-high voltage porcelain-insulated surge arresters are only suitable for areas with seismic acceleration not exceeding 0.3g and altitudes of 3000 meters and below. For use in areas with seismic acceleration greater than 0.3g and altitudes above 3000 meters, it is necessary to further increase the diameter and height of the porcelain-insulated surge arrester, which is not feasible with the porcelain-insulated manufacturing process.

[0005] Therefore, how to improve the seismic resistance of ultra-high voltage surge arresters is a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide an ultra-high voltage surge arrester to improve the seismic resistance of ultra-high voltage surge arresters.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] An ultra-high voltage surge arrester includes multiple surge arrester elements stacked in series, wherein the surge arrester element located at the top is provided with a first terminal and the surge arrester element located at the bottom is provided with a second terminal.

[0009] The second terminal is led out from the side of the connecting flange at the lower end of the surge arrester element located at the bottom, and is insulated from the connecting flange. The second terminal is used for electrical connection with the monitoring device and the grounding terminal.

[0010] The surge arrester element includes a composite jacket and a resistor column disposed inside the composite jacket. The surge arrester element has a first end cap at both ends, and the outer diameter of the composite jacket of the surge arrester element located at the bottom is larger than the outer diameter of the composite jacket of the surge arrester element located at the top.

[0011] Optionally, in the above-mentioned ultra-high voltage surge arresters, the composite housing of each of the surge arrester elements includes:

[0012] The first insulating cylinder, wherein the resistive plate pillar is disposed inside the first insulating cylinder;

[0013] Connecting flanges are fitted onto both ends of the first insulating cylinder;

[0014] An insulating umbrella sleeve is fitted over the outside of the first insulating cylinder and is located between the connecting flanges at both ends of the first insulating cylinder.

[0015] Optionally, in the above-mentioned UHV surge arrester, there are five surge arrester elements, which are, from top to bottom, the first surge arrester element, the second surge arrester element, the third surge arrester element, the fourth surge arrester element and the fifth surge arrester element;

[0016] The outer diameter ratio of the first insulating cylinder of the first surge arrester element, the second surge arrester element, the third surge arrester element, the fourth surge arrester element and the fifth surge arrester element is: 1:(1.1~1.14):(1.1~1.14):(1.2~1.4):(1.2~1.4).

[0017] Optionally, in the above-mentioned UHV surge arrester, the wall thickness ratio of the first insulating cylinder of the first surge arrester element, the second surge arrester element, the third surge arrester element, the fourth surge arrester element and the fifth surge arrester element is: 1:(1.3~1.4):(1.3~1.4):(1.45~1.55):(1.45~1.55).

[0018] Optionally, in the above-mentioned ultra-high voltage surge arresters, the first insulating cylinder of each surge arrester element is made of epoxy glass fiber;

[0019] The connecting flange at the lower end of the fifth surge arrester element is made of ductile iron, and the connecting flange at the upper end of the fifth surge arrester element is made of cast aluminum alloy.

[0020] The connecting flanges at both ends of the first surge arrester element, the second surge arrester element, the third surge arrester element, and the fourth surge arrester element are all made of cast aluminum alloy.

[0021] Optionally, in the above-mentioned UHV surge arresters, each of the surge arrester elements includes four resistor columns connected in parallel;

[0022] A capacitor post is connected in parallel next to a portion of the surge arrester element or a section of the resistor column of the surge arrester element, and the capacitor post is located in the middle of the four resistor columns.

[0023] Optionally, in the above-mentioned ultra-high voltage surge arrester, the bottom of the resistor column is supported on a support plate, and the top of the resistor column is pressed against the first end cap at the upper end of the surge arrester element by a compression spring.

[0024] The support plate is fixed to the first end cap at the lower end of the surge arrester element, and the resistor column and the capacitor column are fixed by a plurality of insulating rods arranged around them;

[0025] The lower end of the insulating rod is fixed to the support plate by threads.

[0026] Optionally, in the above-mentioned ultra-high voltage surge arrester, the first insulating cylinder is provided with a plurality of fixing plates evenly distributed on the resistor column, the fixing plate is provided with limiting holes for the capacitor column and the insulating rod to pass through, and the upper end of the insulating rod is fixed to the fixing plate at the upper end of the resistor column by a nut;

[0027] The fixing plate has mounting holes for installing metal conductors at positions corresponding to the resistor column. The metal conductors are used to electrically connect the resistor columns to the resistors on the upper and lower sides of the metal conductors.

[0028] Optionally, in the above-mentioned ultra-high voltage surge arrester, an explosion-proof plate is fixed to the side of the first end cover away from the resistor column by a first pressure plate, and a sealing ring is provided between the explosion-proof plate and the first end cover and between the end faces of the first end cover and the connecting flange.

[0029] Optionally, in the above-mentioned ultra-high voltage surge arrester, the resistor column is composed of multiple resistors and metal pads stacked in series, so as to adjust the required height of the resistor column and the composite jacket by the number of metal pads.

[0030] Optionally, in the above-mentioned ultra-high voltage surge arrester, the capacitor column includes:

[0031] The second insulating cylinder has second end caps at both ends, and the second end cap located at the upper part of the second insulating cylinder is connected to a compression spring.

[0032] The capacitor core includes multiple capacitors arranged in series and stacked, and is disposed inside the second insulating cylinder. The number of the capacitors is the same as the number of resistors in the resistor column connected in parallel with the capacitor column, and each capacitor and the resistor in parallel are located at the same height.

[0033] Optionally, in the above-mentioned ultra-high voltage surge arrester, the capacitor core is composed of multiple capacitors and metal pads stacked in series, so as to adjust the required height of the capacitor core and the second insulating cylinder by adjusting the number of metal pads.

[0034] Optionally, in the above-mentioned ultra-high voltage surge arrester, at least three insulating rods are evenly distributed around each of the resistor columns; and / or,

[0035] The clearance between the outer diameter of the fixing plate and the inner diameter of the first insulating cylinder is 2mm to 3mm; and / or,

[0036] The outer circumferential surface of the fixing plate is provided with multiple V-shaped grooves to provide channels for gas flow; and / or,

[0037] The fixing plate is made of epoxy glass fiber or polyester material; and / or,

[0038] The bottom of the support plate of the surge arrester element located at the bottom is provided with a support boss to form a pressure relief channel.

[0039] Optionally, in the above-mentioned ultra-high voltage surge arrester, the second terminal is electrically connected to the bottom end of the resistor column through the first connecting plate, the second connecting plate and the third connecting plate;

[0040] The first connecting plate is electrically connected to the bottom end of the resistor column;

[0041] One end of the second connecting plate is electrically connected to the first connecting plate, and the other end is electrically connected to the third outgoing terminal.

[0042] The third connecting plate is electrically connected to the third outgoing terminal and the second wiring terminal, respectively.

[0043] Optionally, in the above-mentioned ultra-high voltage surge arrester, a sampling resistor is provided on the lower side of the contact position between the first connecting plate and the resistor element of the resistor element column.

[0044] Optionally, in the above-mentioned ultra-high voltage surge arrester, the third outgoing terminal passes through the first end cover, and the third outgoing terminal is fixed on the first end cover by the second pressure plate, and the third outgoing terminal is insulated from the first end cover, and a sealing ring is provided between the third outgoing terminal and the first end cover.

[0045] Optionally, in the above-mentioned ultra-high voltage surge arrester, the second terminal passes through the side of the connecting flange and is fixed to the outer wall of the connecting flange by a third pressure plate, and the second terminal is insulated from the connecting flange.

[0046] Optionally, in the above-mentioned ultra-high voltage surge arrester, there are two third pressure plates, and the two third pressure plates are half-flange structures with arc-shaped opening grooves covering the outside of the second terminal, and the inner diameter of the arc-shaped opening grooves is the same as the outer diameter of the second terminal. The third pressure plates are fixed to the outer wall of the connecting flange by screws.

[0047] Optionally, in the above-mentioned ultra-high voltage surge arrester, a current sensor is installed on the third connecting plate, and the current sensor is a Hall element or a Rogowski coil.

[0048] Optionally, the above-mentioned ultra-high voltage surge arrester also includes an equalizing ring and an anti-corona ring welded together, and the equalizing ring and the anti-corona ring are disposed on the top of the surge arrester element.

[0049] Both the equalizing ring and the anti-corona ring are made of aluminum alloy tubing.

[0050] The ultra-high voltage surge arrester provided by this invention is composed of multiple surge arrester elements of different diameters stacked in series. The outer diameter of the composite sleeve of the surge arrester element located at the bottom is larger than that of the composite sleeve of the surge arrester element located at the top. Because the composite sleeve of the bottom surge arrester element is larger, the center of gravity of the ultra-high voltage surge arrester can be lowered, improving its stability and thus its seismic resistance. Furthermore, this invention extends the second terminal from the side of the connecting flange at the lower end of the bottom surge arrester element, eliminating the need for an insulating base for installing monitoring devices compared to existing technologies, and reducing the height of the ultra-high voltage surge arrester. Verification has shown that this invention can meet the requirements for use in areas with seismic acceleration of 0.5g and altitudes of 4000 meters and below. This invention is applicable to areas with high altitude, high seismic intensity, and high pollution levels, and features strong seismic resistance, high mechanical strength, and light weight. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 This is a schematic diagram of the structure of an ultra-high voltage surge arrester provided in an embodiment of the present invention;

[0053] Figure 2 This is a partial cross-sectional view of the bottom of an ultra-high voltage surge arrester provided in an embodiment of the present invention;

[0054] Figure 3 for Figure 2 A magnified view of a portion of the image;

[0055] Figure 4 A cross-sectional view of an ultra-high voltage surge arrester provided in an embodiment of the present invention;

[0056] Figure 5 This is a cross-sectional view of a capacitor column provided in an embodiment of the present invention.

[0057] The meanings of the various reference numerals in the figure are as follows:

[0058] 101 is an equalizing ring; 102 is the first surge arrester element; 103 is the second surge arrester element; 104 is the third surge arrester element; 105 is the fourth surge arrester element; 106 is the fifth surge arrester element; 107 is an anti-corona ring; 108 is the first terminal block; 109 is the second terminal block; 110 is a resistor column; 111 is a composite outer sleeve; 112 is an insulating umbrella sleeve; 113 is the first insulating cylinder; 114 is a connecting flange; 115 is the first end cap; 116 is the first pressure plate. 17 is a fixed plate, 1171 is a metal conductor, 118 is an insulating rod, 119 is a first connecting plate, 120 is a second connecting plate, 121 is a sampling resistor, 122 is a metal pad, 123 is a support plate, 124 is a third pressure plate, 125 is a third connecting plate, 126 is a current sensor, 127 is a second pressure plate, 128 is a third output terminal, 129 is an explosion-proof plate, 130 is a capacitor post, 131 is a capacitor, 132 is a resistor, and 133 is a second insulating cylinder. Detailed Implementation

[0059] The core of this invention is to provide an ultra-high voltage surge arrester to improve the seismic resistance of ultra-high voltage surge arresters.

[0060] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0061] like Figure 1 and Figure 2 As shown in the figure, an ultra-high voltage surge arrester is disclosed in this embodiment of the invention, which includes multiple surge arrester elements stacked in series. The surge arrester element located at the top is provided with a first terminal 108, and the surge arrester element located at the bottom is provided with a second terminal 109.

[0062] The second terminal 109 extends from the side of the connecting flange 114 located at the lower end of the surge arrester element and is insulated from the connecting flange 114. The second terminal 109 is used for electrical connection with the monitoring device and the grounding terminal. Compared with the arrangement of the second terminal 109 in the prior art, the side-outlet method eliminates the need for an insulating base for the monitoring device at the bottom of the UHV surge arrester, thus reducing the height of the UHV surge arrester.

[0063] Each surge arrester element includes a composite housing 111 and resistor columns 110 disposed inside the composite housing 111. Multiple resistor columns 110 can be configured as needed. First end caps 115 are provided at both ends of the surge arrester element to house the resistor columns 110 inside the composite housing 111. The outer diameter of the composite housing 111 of the bottom surge arrester element is larger than that of the top surge arrester element, resulting in a higher bending modulus of the composite housing of the bottom surge arrester element and a lower center of gravity for the UHV surge arrester, thus improving stability.

[0064] The ultra-high voltage surge arrester provided by this invention is composed of multiple surge arrester elements of different diameters stacked in series. The outer diameter of the composite jacket 111 of the surge arrester element located at the bottom is larger than that of the composite jacket 111 of the surge arrester element located at the top. Because the composite jacket 111 of the surge arrester element at the bottom is larger, the center of gravity of the ultra-high voltage surge arrester can be lowered and the bending modulus of the bottom section can be increased, thereby improving the stability of the ultra-high voltage surge arrester and thus its seismic resistance. Furthermore, this invention leads the second terminal 109 out from the side of the connecting flange 114 at the lower end of the surge arrester element located at the bottom, eliminating the need for an insulating base for installing monitoring devices compared to existing technologies, and reducing the height of the ultra-high voltage surge arrester. Verification has shown that this invention can meet the requirements for use in areas with seismic acceleration of 0.5g and an altitude of 4000 meters and below. This invention is applicable to areas with high altitude, high seismic intensity, and high pollution levels, and features strong seismic resistance, high mechanical strength, and light weight.

[0065] like Figure 2 As shown, the composite jacket 111 of each surge arrester element includes a first insulating cylinder 113, a connecting flange 114, and an insulating awning 112.

[0066] The resistor column 110 is disposed inside the first insulating cylinder 113, and the connecting flange 114 is sleeved on both ends of the first insulating cylinder 113. The first end cap 115 is sealed and fixed to the connecting flange 114 at both ends of the first insulating cylinder 113. Since the various surge arrester elements of the present invention adopt an unequal diameter design, that is, the outer diameter of the first insulating cylinder 113 of each surge arrester element can be designed to be different, or partially different and partially the same, so the size of the connecting flange 114 that mates with the first insulating cylinder 113 of each surge arrester element is also different. The size of the connecting flange 114 should be adapted to the size of the corresponding first insulating cylinder 113.

[0067] Two adjacent surge arrester elements are connected via connecting flanges 114. An insulating sheath 112 is fitted over the first insulating cylinder 113 and located between the connecting flanges 114 at both ends of the first insulating cylinder 113. The insulating sheath 112 can be manufactured by injection molding, similar to existing technologies.

[0068] In one specific embodiment of the present invention, there are five surge arrester elements. Those skilled in the art will understand that the specific number of surge arrester elements can be set according to usage requirements. This article uses five as an example for description. The five surge arrester elements are, from top to bottom, the first surge arrester element 102, the second surge arrester element 103, the third surge arrester element 104, the fourth surge arrester element 105, and the fifth surge arrester element 106.

[0069] The outer diameter ratio of the first insulating cylinder 113 of the first surge arrester element 102, the second surge arrester element 103, the third surge arrester element 104, the fourth surge arrester element 105 and the fifth surge arrester element 106 is 1:(1.1~1.14):(1.1~1.14):(1.2~1.4):(1.2~1.4).

[0070] That is, the outer diameter of the first insulating cylinder 113 of the first surge arrester element 102 is the smallest. The outer diameters of the first insulating cylinders 113 of the second surge arrester element 103 and the third surge arrester element 104 can be designed to be the same and larger than the outer diameter of the first insulating cylinder 113 of the first surge arrester element 102. The outer diameters of the first insulating cylinders 113 of the fourth surge arrester element 105 and the fifth surge arrester element 106 can be designed to be the same and larger than the outer diameters of the first insulating cylinders 113 of the second surge arrester element 103 and the third surge arrester element 104.

[0071] Preferably, the outer diameter ratio of the first insulating cylinder 113 of the first surge arrester element 102, the second surge arrester element 103, the third surge arrester element 104, the fourth surge arrester element 105 and the fifth surge arrester element 106 can be 1:1.12:1.12:1.3:1.3, so as to lower the center of gravity of the UHV surge arrester and realize the equal margin design of the mechanical strength of the surge arrester elements in different installation positions.

[0072] In order to further reduce the center of gravity of the UHV surge arrester and increase the bending modulus of the bottom section, in a specific embodiment of the present invention, the first insulating cylinder 113 of each surge arrester element adopts a design with unequal wall thickness, that is, the first insulating cylinder 113 located above is designed with a thinner wall thickness, and the first insulating cylinder 113 located below is designed with a thicker wall thickness.

[0073] Specifically, the wall thickness ratio of the first insulating cylinder 113 of the first surge arrester element 102, the second surge arrester element 103, the third surge arrester element 104, the fourth surge arrester element 105 and the fifth surge arrester element 106 is: 1:(1.3~1.4):(1.3~1.4):(1.45~1.55):(1.45~1.55).

[0074] That is, the first insulating cylinder 113 of the first surge arrester element 102 has the smallest wall thickness. The wall thickness of the first insulating cylinder 113 of the second surge arrester element 103 and the third surge arrester element 104 can be designed to be the same, and greater than the wall thickness of the first insulating cylinder 113 of the first surge arrester element 102. The wall thickness of the first insulating cylinder 113 of the fourth surge arrester element 105 and the fifth surge arrester element 106 can be designed to be the same, and greater than the wall thickness of the first insulating cylinder 113 of the second surge arrester element 103 and the third surge arrester element 104.

[0075] Preferably, the outer diameter ratio of the first insulating cylinder 113 of the first surge arrester element 102, the second surge arrester element 103, the third surge arrester element 104, the fourth surge arrester element 105 and the fifth surge arrester element 106 can be 1:1.35:1.35:1.5:1.5, so as to further reduce the center of gravity of the UHV surge arrester and increase the bending modulus of the bottom section, thereby realizing the equal margin design of the mechanical strength of the surge arrester elements in different installation positions.

[0076] Furthermore, the first insulating cylinder 113 of each surge arrester element is made of epoxy glass fiber, the connecting flange 114 at the lower end of the fifth surge arrester element 106 is made of ductile iron, and the connecting flange 114 at the upper end of the fifth surge arrester element 106 is made of cast aluminum alloy; the connecting flanges 114 at both ends of the first surge arrester element 102, the second surge arrester element 103, the third surge arrester element 104, and the fourth surge arrester element 105 are all made of cast aluminum alloy. This embodiment of the invention, by using a first insulating cylinder 113 made of high-strength epoxy glass fiber with varying diameters and wall thicknesses, and by using ductile iron for the bottom connecting flange 114 and lighter cast aluminum alloy for the remaining connecting flanges 114, further reduces the center of gravity and weight of the ultra-high voltage surge arrester, thereby improving its mechanical strength.

[0077] like Figure 4 and Figure 5 As shown, each surge arrester element includes four resistor columns 110 connected in parallel. Some surge arrester elements are provided with capacitor columns 130 connected in parallel with the resistor columns 110, or capacitor columns 130 are connected in parallel with a portion of the resistor columns 110 of the surge arrester element, and the capacitor columns 130 are located in the middle of the four resistor columns 110.

[0078] Due to the influence of stray capacitance to ground, the voltage distribution along the axial direction of the UHV surge arrester is uneven. This invention, through the equalizing ring 101 and the parallel capacitor column 130, improves the axial voltage distribution of the UHV surge arrester, reduces the deviation of the operating voltage borne by the resistor elements, and ensures that the operating voltage borne by each resistor element 132 of the UHV surge arrester is uniform and consistent, with a control deviation of no more than 10%. This reduces the operating charge rate of the resistor elements of the UHV surge arrester and improves the long-term stability of the UHV surge arrester. The capacitor column 130 can be configured according to the needs of controlling the voltage deviation borne by each arrester element and each resistor element of the UHV surge arrester.

[0079] like Figure 2 As shown, the bottom of the resistor column 110 is supported on the support plate 123, and the top of the resistor column 110 is pressed against the first end cap 115 at the upper end of the surge arrester element by a compression spring. The support plate 123 is fixed to the first end cap 115 at the lower end of the surge arrester element. The resistor column 110 and the capacitor column 130 are fixed by a plurality of insulating rods 118 arranged around them. The lower end of the insulating rod 118 is fixed to the support plate 123 by threads, and the upper end of the insulating rod 118 is fixed to the fixing plate 117 at the upper end of the resistor column 110 by engaging with a nut. The support plate 123 can be fixed to the first end cap 115 by screws. It should be noted that the fixing method of each resistor element of the resistor column 110 within the composite jacket 111 can be the same as that in the prior art, and will not be described in detail here.

[0080] like Figure 2 and Figure 4 As shown, in order to further fix the resistor column 110 and the capacitor column 130, in this embodiment, a plurality of fixing plates 117 evenly distributed on the resistor column 110 are provided in the first insulating cylinder 113 of each surge arrester element.

[0081] The fixing plate 117 is provided with a limiting hole for the capacitor post 130 and the insulating rod 118 to pass through, thereby restricting the radial movement of the insulating rod 118 and the capacitor post 130. Since the insulating rod 118 is used to fix the resistor post 110, it can also restrict the radial movement of the resistor post 110.

[0082] The fixing plate 117 has mounting holes for mounting the metal conductor 1171 at the position corresponding to the resistor column 110. The diameter of the mounting holes is smaller than the diameter of the resistor 132. The metal conductor 1171 is used to electrically connect the resistor 132 on the upper and lower sides of the resistor column 110. Therefore, the fixing plate 117 can also restrict the resistor column 110 from moving axially.

[0083] When an internal short-circuit fault occurs in the surge arrester, the internal gas pressure rises. To prevent the surge arrester casing from rupturing, in a specific embodiment of the present invention, an explosion-proof plate 129 is fixed to the side of the first end cover 115 away from the resistor column 110 by a first pressure plate 116. Sealing rings are provided between the explosion-proof plate 129 and the first end cover 115, and between the end faces of the first end cover 115 and the connecting flange 114. Vent holes are provided between the first end cover 115 and the explosion-proof plate 129. When an internal short-circuit fault occurs in the surge arrester, the internal gas will break through the explosion-proof plate 129 and be discharged through the vent holes without rupturing and damaging other equipment.

[0084] The resistor column 110 is composed of multiple resistors 132 and metal pads stacked in series. The required height of the resistor column 110 and the composite jacket 111 is adjusted by the number of metal pads, so that the height of the resistor column 110 can be pressed tightly within the composite jacket 111. The resistor 132 is made of ZnO with Bi2O3, Sb2O3, Ni2O3, MnO2, Co2O3, SiO2, and Er2O3 added in a certain proportion. It is manufactured through ball milling, mixing, granulation, molding, glazing, debinding, firing, grinding, and aluminum spraying processes. Its voltage gradient is 300V / mm, the voltage reduction ratio under a lightning impulse current of 10kA is not greater than 1.5, and the energy density is not less than 290J / cm³. 3 This achieves excellent protection performance of ultra-high voltage surge arresters.

[0085] like Figure 4 and Figure 5 As shown, in a specific embodiment of the present invention, the capacitor post 130 includes a second insulating cylinder 133 and a capacitor core. Second end caps are provided at both ends of the second insulating cylinder 133, and a compression spring is connected to the upper end cap of the second insulating cylinder 133 to press the capacitor core tightly within the second insulating cylinder 133. The capacitor core includes a plurality of capacitors 131 arranged in series and stacked, and is disposed within the second insulating cylinder 133. The number of capacitors 131 is the same as the number of resistors 132 in the resistor column 110 connected in parallel with the capacitor post 130, and each capacitor 131 and the parallel resistors 132 are located at the same height.

[0086] Furthermore, the capacitor core is composed of multiple capacitors 131 and metal pads stacked in series. The number of metal pads is used to adjust the required height of the capacitor core in conjunction with the second insulating cylinder 133, so that the height of the capacitor core can be pressed tightly within the second insulating cylinder 133. The capacitor column 130 can be a single column, or multiple columns can be arranged in parallel as needed.

[0087] In a specific embodiment of the present invention, at least three insulating rods 118 are evenly distributed around each resistor column 110. In the scheme disclosed in this embodiment, five insulating rods 118 are provided for each resistor column 110. Those skilled in the art can select the number of insulating rods 118 corresponding to each resistor column 110 according to the size of the UHV surge arrester.

[0088] The fitting clearance between the outer diameter of the fixing plate 117 and the inner diameter of the first insulating cylinder 113 is 2mm to 3mm. Multiple V-grooves are provided on the outer circumferential surface of the fixing plate 117 to provide a channel for gas flow. These V-grooves can be used to provide axial flow space for gas. The fixing plate 117 is made of epoxy fiberglass material. The bottom of the support plate 123 of the surge arrester element at the bottom is provided with a support boss, allowing the support plate 123 to contact the first end cover 115 with a small area, without excessively occupying the space above the first end cover 115, thus forming a pressure release channel. This prevents the support plate 123 from obstructing the gas when the pressure increases rapidly, allowing the pressure to be released quickly through the explosion-proof plate 129.

[0089] like Figure 2 and Figure 3 As shown, in a specific embodiment of the present invention, the second terminal 109 is electrically connected to the bottom end of the resistor post 110 via a first connecting plate 119, a second connecting plate 120, and a third connecting plate 125. The first connecting plate 119, made of metal, is electrically connected to the bottom end of the resistor post 110. One end of the second connecting plate 120 is electrically connected to the first connecting plate 119, specifically by fastening the second connecting plate 120 and the first connecting plate 119 with bolts. The other end of the second connecting plate 120 is electrically connected to the third output terminal 128, specifically by fastening the second connecting plate 120 and the third output terminal 128 with bolts. The third connecting plate 125 is electrically connected to both the third output terminal 128 and the second terminal 109, both of which are electrically connected by fastening bolts. This invention enables the bottom end of the resistor column 110 to be electrically connected to the second terminal 109, and the second terminal 109 to be led out from the side, eliminating the need for a supporting insulating base and reducing the height of the ultra-high voltage surge arrester.

[0090] Furthermore, a sampling resistor 121 is provided on the lower side of the contact position between the first connecting plate 119 and the resistor piece 132 of the resistor piece column 110, and a metal pad 122 with a recess is provided at the bottom end of the sampling resistor 121. The sampling resistor 121 is coaxially arranged with the four-post resistor piece column 110, and the resistance value of the sampling resistor 121 is higher than the internal resistance of the monitoring device. The low-voltage end of the sampling resistor 121 is at the same potential as the connecting flange 114, thus realizing the insulation between the first connecting plate 119 and the connecting flange 114 and the function of the current sensor of the monitoring device connected to the second terminal 109, as well as the steady-state current measurement of the UHV surge arrester.

[0091] In one specific embodiment of the present invention, the third output terminal 128 passes through the first end cover 115 and is fixed to the first end cover 115 by a second pressure plate 127. The second pressure plate 127 is fixed to the lower side of the first end cover 115 by screws. The third output terminal 128 is insulated from the first end cover 115, and a sealing ring is provided between the third output terminal 128 and the first end cover 115. The third output terminal 128 can be made by pressing epoxy resin insulating material onto the outer surface of a metal rod. The two ends of the metal rod of the third output terminal 128 are provided with terminals for electrical connection with the second connecting plate 120 and the third connecting plate 125.

[0092] In one specific embodiment of the present invention, the second terminal 109 passes through the side of the connecting flange 114 and is fixed to the outer wall of the connecting flange 114 by a third pressure plate 124, which is made of metal. To facilitate the installation of the third pressure plate 124, two third pressure plates 124 can be provided, forming a half-flange structure. This can be understood as dividing a complete flange structure into two parts along its axis. The third pressure plate 124 has an arc-shaped opening groove covering the outside of the second terminal 109, and the inner diameter of the arc-shaped opening groove is the same as the outer diameter of the second terminal 109. The third pressure plate 124 is fixed to the outer wall of the connecting flange 114 by screws, and the second terminal 109 is insulated from the connecting flange 114. The second terminal 109 can be made by pressing silicone rubber material onto the outer surface of a metal rod, and terminal blocks are provided at both ends of the metal rod of the second terminal 109 for easy wiring.

[0093] Furthermore, a current sensor 126 is installed on the third connecting plate 125. The current sensor 126 can be a Hall element or a Rogowski coil, which can realize the measurement of the transient current of the UHV surge arrester.

[0094] like Figure 1As shown, in a specific embodiment of the present invention, the ultra-high voltage surge arrester may further include an equalizing ring 101 and an anti-corona ring 107 welded together, and the equalizing ring 101 and the anti-corona ring 107 are disposed on the top of the surge arrester element, that is, on the top of the first surge arrester element 102. The equalizing ring 101 and the anti-corona ring 107 may both be made of aluminum alloy tubing, which improves mechanical strength and facilitates installation.

[0095] By setting up an equalizing ring 101 and an anti-corona ring 107, this invention further improves the voltage distribution along the axial direction of the UHV surge arrester, making the operating voltage borne by each resistor element of the UHV surge arrester uniform and consistent, reducing the operating charge rate of the resistor elements of the UHV surge arrester, and improving the long-term stability of the UHV surge arrester.

[0096] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0097] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "a," and / or "the" are not specifically singular and may include the plural. Generally, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements. An element defined by the phrase "comprising an..." does not exclude the presence of other identical elements in the process, method, product, or apparatus that includes the element.

[0098] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0099] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. An extra-high voltage surge arrester, characterized by, The lightning arrester element includes a plurality of lightning arrester elements stacked in series, the lightning arrester element at the top is provided with a first connecting terminal (108), and the lightning arrester element at the bottom is provided with a second connecting terminal (109); The second connecting terminal (109) is led out from the side of the connecting flange (114) at the lower end of the lightning arrester element at the bottom and is insulated from the connecting flange (114), and the second connecting terminal (109) is used for electrical connection with a monitoring device and a grounding terminal; The lightning arrester element includes a composite outer sleeve (111) and a resistance disc column (110) arranged inside the composite outer sleeve (111), and the lightning arrester element is provided with a first end cover (115) at both ends, and the outer diameter of the composite outer sleeve (111) of the lightning arrester element at the bottom is greater than the outer diameter of the composite outer sleeve (111) of the lightning arrester element at the top; The second connecting terminal (109) is electrically connected with the bottom end of the resistance disc column (110) through a first connecting plate (119), a second connecting plate (120) and a third connecting plate (125); The first connecting plate (119) is electrically connected with the bottom end of the resistance disc column (110); One end of the second connecting plate (120) is electrically connected with the first connecting plate (119), and the other end is electrically connected with a third connecting terminal (128); The third connecting plate (125) is electrically connected with the third connecting terminal (128) and the second connecting terminal (109) respectively; A current sensor (126) is installed on the third connecting plate (125); The voltage equalizing ring (101) and the anti-corona ring (107) are further included, and the voltage equalizing ring (101) and the anti-corona ring (107) are arranged at the top of the lightning arrester element at the top.

2. The UHV surge arrester of claim 1, characterized by The composite outer sleeve (111) of each lightning arrester element includes: A first insulating cylinder (113) in which the resistance disc column (110) is arranged; A connecting flange (114) sleeved at both ends of the first insulating cylinder (113); An insulating umbrella sleeve (112) sleeved outside the first insulating cylinder (113) and between the connecting flanges (114) at both ends of the first insulating cylinder (113).

3. The UHV surge arrester of claim 2, wherein The lightning arrester element is five, and from top to bottom, they are a first lightning arrester element (102), a second lightning arrester element (103), a third lightning arrester element (104), a fourth lightning arrester element (105) and a fifth lightning arrester element (106); The outer diameters of the first insulating cylinders (113) of the first lightning arrester element (102), the second lightning arrester element (103), the third lightning arrester element (104), the fourth lightning arrester element (105) and the fifth lightning arrester element (106) are in the ratio of 1:(1.1-1.14):(1.1-1.14):(1.2-1.4):(1.2-1.4).

4. The UHV surge arrester of claim 3, wherein, The wall thickness ratio of the first insulating cylinder (113) of the first arrester element (102), the second arrester element (103), the third arrester element (104), the fourth arrester element (105) and the fifth arrester element (106) is: 1: (1.3-1.4): (1.3-1.4): (1.45-1.55): (1.45-1.55).

5. The UHV surge arrester of claim 3, wherein, The material of the first insulating cylinder (113) of each arrester element is epoxy glass silk; The material of the connecting flange (114) at the lower end of the fifth arrester element (106) is nodular cast iron, and the material of the connecting flange (114) at the upper end of the fifth arrester element (106) is cast aluminum alloy; The material of the connecting flange (114) at both ends of the first arrester element (102), the second arrester element (103), the third arrester element (104) and the fourth arrester element (105) is cast aluminum alloy.

6. The UHV surge arrester of claim 3, wherein, Each of the arrester elements includes four parallel resistor column (110); Some of the arrester elements or some of the resistor columns (110) of the arrester elements are connected in parallel with a capacitor column (130), and the capacitor column (130) is arranged in the middle of the four resistor columns (110).

7. The UHV surge arrester of claim 6, characterized by The bottom of the resistor column (110) is supported on the support plate (123), and the top of the resistor column (110) is tightly pressed against the first end cover (115) at the upper end of the arrester element by a compression spring; The support plate (123) is fixed to the first end cover (115) at the lower end of the arrester element, and the resistor column (110) and the capacitor column (130) are fixed by a plurality of insulating rods (118) arranged around them; The lower end of the insulating rod (118) is fixed to the support plate (123) by a screw thread.

8. The UHV surge arrester of claim 7, characterized by A plurality of fixing plates (117) are arranged in the first insulating cylinder (113) and uniformly distributed on the resistor column (110), the fixing plate (117) is provided with a limiting hole for the capacitor column (130) and the insulating rod (118) to pass through, and the upper end of the insulating rod (118) is fixed to the fixing plate (117) at the upper end of the resistor column (110) by a nut; The fixing plate (117) is provided with a mounting hole for mounting a metal conductor (1171) at a position corresponding to the resistor column (110), and the metal conductor (1171) is used to electrically connect the resistor sheets (132) on the upper and lower sides of the resistor column (110).

9. The UHV surge arrester of claim 7, wherein, The side of the first end cover (115) away from the resistor column (110) is fixed with an explosion-proof plate (129) by a first pressing plate (116), and a sealing ring is arranged between the explosion-proof plate (129) and the first end cover (115) and between the end face of the first end cover (115) and the connecting flange (114).

10. The UHV surge arrester of claim 8, wherein, The resistance column (110) is composed of a plurality of resistance sheets (132) and metal pads in series, so that the required height of the resistance column (110) matched with the composite sleeve (111) is adjusted by the number of the metal pads.

11. The UHV surge arrester of claim 8, wherein, The capacitor column (130) comprises: A second insulating cylinder (133) is provided with second end covers at both ends, and a compression spring is connected to the second end cover at the upper part of the second insulating cylinder (133); The capacitor core comprises a plurality of capacitors (131) arranged in series, and is arranged in the second insulating cylinder (133), the number of the capacitors (131) is the same as the number of the resistance sheets (132) of the resistance column (110) in parallel with the capacitor column (130), and each capacitor (131) is at the same height as the parallel resistance sheet (132).

12. The UHV surge arrester of claim 11, characterized by The capacitor core is composed of a plurality of capacitors (131) and metal pads in series, so that the required height of the capacitor core matched with the second insulating cylinder (133) is adjusted by the number of the metal pads.

13. The UHV surge arrester of claim 8, wherein, At least three insulating rods (118) are uniformly distributed around each resistance column (110); and / or, The gap between the outer diameter of the fixed plate (117) and the inner diameter of the first insulating cylinder (113) is 2-3 mm; and / or, A plurality of V-shaped grooves are arranged on the outer circumferential surface of the fixed plate (117) to provide a channel for gas flow; and / or, The material of the fixed plate (117) is epoxy glass or polyester material; and / or, The bottom of the support plate (123) of the lightning arrester element at the bottom is provided with a support boss to form a pressure release channel.

14. The UHV surge arrester of claim 1, wherein, The sampling resistor (121) is arranged at the lower side of the position where the resistance sheet (132) of the resistance column (110) is attached.

15. The UHV surge arrester of claim 1, wherein, The third outgoing terminal (128) passes through the first end cover (115), is fixed on the first end cover (115) by a second pressing plate (127), and is insulated from the first end cover (115), and a sealing ring is arranged between the third outgoing terminal (128) and the first end cover (115).

16. The UHV surge arrester of claim 1, wherein, The second wiring terminal (109) passes through the side surface of the connecting flange (114) and is fixed on the outer side wall of the connecting flange (114) by a third pressing plate (124), and the second wiring terminal (109) is insulated from the connecting flange (114).

17. The UHV surge arrester of claim 16, wherein, The third pressing plate (124) is two, and the two third pressing plates (124) are half-flange structures with arc-shaped open grooves wrapped outside the second wiring terminal (109), and the inner diameter of the arc-shaped open groove is the same as the outer diameter of the second wiring terminal (109), and the third pressing plate (124) is fixed on the outer side wall of the connecting flange (114) by screws.

18. The UHV surge arrester of claim 1, wherein, The current sensor (126) is a Hall element or a Rogowski coil.

19. The UHV surge arrester of claim 1, wherein, The voltage equalizing ring (101) and the anti-corona ring (107) are welded together; The equalizing ring (101) and the anti-blooming ring (107) are both made of aluminum alloy tubes.

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