Quick-mounting type PT overvoltage suppression assembly

Abstract

The utility model discloses a quick-mounting type PT overvoltage suppression assembly which comprises a primary resonance eliminator and further comprises a grounding point, the grounding point is located below the primary resonance eliminator, a through hole is formed in the grounding point, a rectangular groove is formed in the primary resonance eliminator, and the primary resonance eliminator is fixedly installed on the grounding point. The first positioning plate is located in the second groove and is in sliding connection with the extension column. The first positioning plate is used for extending to the joint of the quick-mounting mechanism and the grounding point and limiting the grounding point. The driving assembly is located in the rectangular groove, slidably connected with the rectangular groove and located above the extending column, and the driving assembly is used for driving the extending column to move up and down and controlling the first positioning plate to slide. In the operation process, the second positioning plate can move up and down only by manually rotating the screw rod, and the second positioning plate can be in contact with the grounding point when moving upwards, so that the grounding point is extruded and limited, and the one-time resonance eliminator is effectively and stably mounted on the grounding point.

Description

Technical Field

[0001] The utility model relates to the field of PT overvoltage suppression components, in particular to a quick-installed PT overvoltage suppression component. Background Art

[0002] Dry-type electromagnetic voltage transformers may occasionally fail during long-term use, but frequent failures are very abnormal. It is generally believed that in addition to the quality problems of the equipment itself, the main reason for the electromagnetic voltage transformer high-voltage fuse to blow or even busbar short-circuit failure is the overvoltage of the electromagnetic voltage transformer. In a neutral point ungrounded system or a low-current grounded system, when an unloaded busbar is closed, single-phase arc grounding disappears, or the system load changes drastically, the nonlinear core of the electromagnetic voltage transformer may become saturated, causing the excitation current of the winding to increase rapidly, which can be more than 100 times the rated excitation current in severe cases, causing the voltage transformer high-voltage fuse to blow, and forming a special single-phase or three-phase resonant circuit with the ground capacitance of the line and equipment, resulting in continuous and high-amplitude overvoltage on the equipment in the circuit.

[0003] In order to avoid the frequent occurrence of such faults, suppression components based on the current limiting characteristics of PTC materials are usually installed in series on the ground side of the voltage transformer. Under normal operating conditions, the current limiting resistor presents a low resistance. When the excitation current between the primary winding phase and the ground or between phases increases, the current limiting resistor increases rapidly with the change of the excitation current, and can play a better damping role. Moreover, the larger the excitation current, the faster the current limiting resistor acts. When the system fault disappears, the current limiting resistor recovers quickly.

[0004] However, the installation of this type of suppression component adopts the simplest installation method, such as installation and fixing by bolts and nuts. Although the installation of bolts and nuts is the most cost-effective, it is not the most convenient during operation. Auxiliary tools such as wrenches are required for two-handed operation, which increases the burden on the operator. Utility Model Content

[0005] The utility model aims to provide a quick-install PT overvoltage suppression component to solve the following problems: it is inconvenient to operate, requires auxiliary tools for two-handed operation, and increases the burden on the operator.

[0006] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0007] The quick-install PT overvoltage suppression assembly comprises a primary harmonic eliminator installed on a grounding point, wherein a rectangular groove is provided on the primary harmonic eliminator;

[0008] A quick-installation mechanism, the quick-installation mechanism is located inside the rectangular groove of the primary harmonic eliminator, and the quick-installation mechanism is used for fixed connection between the grounding point and the primary harmonic eliminator;

[0009] The quick-installation mechanism comprises:

[0010] An extension column, wherein first grooves are formed on both left and right sides of the extension column;

[0011] A first positioning plate, the first positioning plate is located inside the first groove and is slidably connected to the extension column, and the first positioning plate is used to extend to the connection between the quick-installation mechanism and the grounding point and limit the grounding point;

[0012] A limit plate, the limit plate is used in conjunction with a first positioning plate to connect the grounding point and the primary harmonic elimination device;

[0013] A driving assembly is located inside the rectangular groove and is slidably connected to the rectangular groove. The driving assembly is located above the extension column and is used to control the sliding of the first positioning plate.

[0014] Preferably, the grounding point is located below the primary harmonic eliminator, and a through hole is provided on the grounding point.

[0015] Preferably, the limit plate is located above the primary harmonic eliminator, and the diameter of the limit plate is greater than the length of the rectangular slot.

[0016] Preferably, a second groove is provided inside the extension column, the second groove is connected to the first groove, and the first groove and the second groove form a T-shape.

[0017] Preferably, the first magnetic block is located inside the second groove and is slidably connected to the extension column;

[0018] A second magnetic block is embedded in the first positioning plate, and the first magnetic block and the second magnetic block magnetically repel each other;

[0019] A rotating shaft, the rotating shaft is located inside the second groove, and the rotating shaft is used to connect the first magnetic block and the driving assembly;

[0020] A limiting bar is located on the top of the first positioning plate and is fixedly connected to the first positioning plate, and is used to limit the movement of the first positioning plate.

[0021] Preferably, a threaded column, the threaded column is located inside the rectangular groove and is slidably connected to the primary harmonic eliminator, the threaded column is located above the extension column and is fixedly connected to the extension column, and the threaded column is fixedly connected to the limit plate;

[0022] A screw rod is located inside the threaded column and is threadedly connected to the threaded column. The screw rod is used to control the extension column and the threaded column to move up and down. The screw rod is rotationally connected to the rotating shaft and is threadedly connected to the limiting plate.

[0023] The beneficial effects of the utility model are:

[0024] 1. During use, the utility model can be directly fixed by rotating the bolt. By setting the threaded column and the limit plate, the limit plate can be fixed on the primary harmonic eliminator or not, which is convenient for preliminary setting according to needs. In addition, during operation, the primary harmonic eliminator can be stably installed on the grounding point only by manually rotating the screw rod, which effectively solves the problem of requiring two-handed operation and makes installation and disassembly more convenient.

[0025] 2. In the process of driving the screw to rotate, the screw drives the rotating shaft to move downward, so that the first magnetic block connected to the screw will be located between the two first positioning plates, thereby interacting with the two second magnetic blocks, so that the first positioning plate moves out of the extension column to act on the grounding point. With the help of the first positioning plate, the connection between the fixed grounding point and the primary harmonic eliminator can be further played. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the structure of the utility model;

[0027] Figure 2 It is a structural schematic diagram of the quick-installation mechanism of the utility model;

[0028] Figure 3 It is a structural schematic diagram of the extension column of the utility model;

[0029] Figure 4 For this utility model Figure 3 A magnified schematic diagram of part A.

[0030] Figure numerals: 1. primary detuning device; 2. grounding point; 3. limit plate; 4. screw; 5. rectangular groove; 6. extension column; 7. rotating shaft; 8. threaded column; 10. limit strip; 11. first magnetic block; 12. first positioning plate. DETAILED DESCRIPTION

[0031] In order to make the technical means, creative features, objectives and effects of the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments and drawings, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work are all within the protection scope of the present invention.

[0032] The specific embodiments of the present utility model are described below in conjunction with the accompanying drawings.

[0033] Example:

[0034] like Figure 1-4As shown, according to existing cases, the overvoltage suppression measures for electromagnetic voltage transformers in neutral point non-effectively grounded systems mainly include changing system parameters and increasing system damping;

[0035] However, in the existing detuning measures of changing system parameters, although the use of high saturation point PT can reduce the probability of resonance, once resonance occurs, the overvoltage and overcurrent will be greater. If a capacitive voltage transformer is selected, the economic efficiency does not meet the requirements for the 10kV distribution network.

[0036] When PT ferromagnetic resonance occurs, the presence of resistor R in the resonant circuit reduces the overvoltage at both ends of capacitor C and inductor L, the resonant working state point moves forward, the resonance range is reduced, and the amplitude of the resonant overvoltage is reduced. If the value of resistor R is greatly increased, only the non-resonant working state point will remain, thus eliminating the possibility of resonance. It can be seen that resistor R has a damping and limiting effect on the resonant overvoltage. When the resistor R in the primary circuit of the PT is large enough, the primary winding excitation inrush current can be limited to avoid saturation of the transformer core, thereby effectively preventing or eliminating resonance, and the higher the R value, the better the detuning effect. However, when the neutral point of the primary side of the PT is connected in series with a resistor, the resistor is too large. When single-phase grounding occurs in the network, most of the zero-sequence voltage drops on the resistor, which will affect the reliable operation of the protection device; and the excessive resistance will cause the neutral point of the voltage transformer to have a long-term operating voltage that is too high, posing a threat to the insulation of the neutral point of the transformer.

[0037] The quick-install PT overvoltage suppression component includes a primary harmonic eliminator 1, and also includes: a grounding point 2 located below the primary harmonic eliminator 1, a through hole is opened on the grounding point 2, a rectangular groove 5 is opened on the primary harmonic eliminator 1, and the primary harmonic eliminator 1 is installed and fixed on the grounding point 2.

[0038] The quick-install mechanism is located inside the rectangular groove 5 of the primary harmonic eliminator 1 and extends to the inside of the through hole of the grounding point 2 . The quick-install mechanism is used for fixed connection between the grounding point 2 and the primary harmonic eliminator 1 .

[0039] The quick-install mechanism includes:

[0040] The left and right sides of the extension column 6 are both provided with first grooves.

[0041] The first positioning plate 12 is located inside the first groove and is slidably connected to the extension column 6 . The first positioning plate 12 is used to extend to the connection between the quick-installation mechanism and the grounding point 2 and limit the grounding point 2 .

[0042] The limiting plate 3 is located above the primary harmonic eliminator 1 , and the diameter of the limiting plate 3 is greater than the length of the rectangular slot 5 .

[0043] The driving assembly is located inside the rectangular groove 5 and is slidably connected to the rectangular groove 5 . The driving assembly is located above the extension column 6 . The driving assembly is used to control the sliding of the first positioning plate 12 .

[0044] A second groove is formed inside the extension column 6 . The second groove is connected to the first groove, and the first groove and the second groove form a T-shape.

[0045] The transverse length of the first positioning plate 12 is smaller than the width of the second groove, that is, the first positioning plate 12 can fall from the upper opening of the second groove, thereby completing the installation of the first positioning plate 12 .

[0046] The first magnetic block 11 is located inside the second groove and is slidably connected to the extension column 6 .

[0047] The first positioning plate 12 is embedded with a second magnetic block, and the first magnetic block 11 and the second magnetic block magnetically repel each other.

[0048] The rotating shaft 7 is located inside the second groove, and the rotating shaft 7 is used to connect the first magnetic block 11 with the driving assembly.

[0049] The limiting strip 10 is located on the top of the first positioning plate 12 and is fixedly connected to the first positioning plate 12 . The limiting strip 10 is used to limit the movement of the first positioning plate 12 .

[0050] The drive components include:

[0051] The threaded column 8 is located inside the rectangular groove 5 and is slidably connected to the primary harmonic eliminator 1 . The threaded column 8 is located above the extension column 6 and is fixedly connected to the extension column 6 . The threaded column 8 is fixedly connected to the limiting plate 3 .

[0052] The screw rod 4 is located inside the threaded column 8 and is threadedly connected to the threaded column 8 . The screw rod 4 is used to control the extension column 6 and the threaded column 8 to move up and down. The screw rod 4 is rotationally connected to the rotating shaft 7 , and the screw rod 4 is threadedly connected to the limit plate 3 .

[0053] The threaded column 8 located inside the rectangular groove 5 can be directly inserted into the primary detuning device 1 for connection. This solution requires the user to install it on the primary detuning device 1 first. Compared with the above operation, there is one more step, but it is convenient for disassembly and can better perform partial replacement for subsequent damage.

[0054] The limiting plate 3 on the rectangular groove 5 may be pre-welded to the primary detuning device 1. In this solution, the user only needs to hold the primary detuning device 1 and align it with the grounding point 2 to connect and operate, which is more convenient.

[0055] After the extension column 6 is inserted into the grounding point 2, the screw rod 4 is rotated. The screw rod 4 is a knob screw rod 4, which is convenient for manual rotation. When the screw rod 4 rotates, the screw rod 4 drives the rotating shaft 7 to move downward.

[0056] In this way, the first magnetic block 11 at the bottom of the rotating shaft 7 will be located between the two first positioning plates 12. Since the second magnetic block is arranged on the first positioning plate 12, the two first positioning plates 12 can be moved out of the extension column 6 by the repulsive force between the first magnetic block 11 and the second magnetic block.

[0057] As the first positioning plate 12 extends outward, the first positioning plate 12 will limit the grounding point 2, so that the primary harmonic eliminator 1 is stably connected to the grounding point 2.

[0058] When the extension column 6 moves downward, the first magnetic block 11 is not located between the two first positioning plates 12 , so the second magnetic blocks on the two first positioning plates 12 are magnetically attracted to each other and return to the inside of the extension column 6 .

[0059] In the prior art, bolts and nuts are used for fixing, which not only requires the use of spring pieces and washers for limiting, but also because the spring pieces and washers themselves are small in size, difficult to install, and easy to fall off, and the installation of bolts and nuts often requires two wrenches to operate, one wrench is used to fix the bolt, and the other wrench is used to turn the nut to achieve the tightening effect. The whole operation process is not convenient and even cumbersome. If the two wrenches in the hands of the operator are not properly matched, the operation cannot be completed. However, in the present invention, the fixing effect equivalent to that of the bolt and nut can be achieved by manually turning the screw rod 4, which greatly improves the convenience.

[0060] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the utility model and are not used to limit the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. A quick-install PT overvoltage suppression assembly, comprising a primary harmonic elimination device (1) installed on a grounding point (2), characterized in that: The primary harmonic eliminator (1) is provided with a rectangular groove (5); A quick-installation mechanism, the quick-installation mechanism being located inside the rectangular groove (5) of the primary harmonic eliminator (1), the quick-installation mechanism being used for fixedly connecting the grounding point (2) and the primary harmonic eliminator (1); The quick-installation mechanism comprises: An extension column (6), wherein first grooves are formed on both left and right sides of the extension column (6); A first positioning plate (12), the first positioning plate (12) being located inside the first groove and being slidably connected to the extension column (6), the first positioning plate (12) being used to extend to the connection between the quick-installation mechanism and the grounding point (2) and to limit the grounding point (2); A limit plate (3), the limit plate (3) being used in conjunction with a first positioning plate (12) for connecting the grounding point (2) and the primary harmonic elimination device (1); A driving assembly, the driving assembly is located inside the rectangular groove (5) and is slidably connected to the rectangular groove (5), the driving assembly is located above the extension column (6), and the driving assembly is used to control the sliding of the first positioning plate (12).

2. The quick-install PT overvoltage suppression assembly according to claim 1 is characterized in that: The grounding point (2) is located below the primary harmonic eliminator (1), and a through hole is provided on the grounding point (2).

3. The quick-install PT overvoltage suppression assembly according to claim 2 is characterized in that: The limiting plate (3) is located above the primary harmonic eliminator (1), and the diameter of the limiting plate (3) is greater than the length of the rectangular groove (5).

4. The quick-install PT overvoltage suppression assembly according to claim 3 is characterized in that: A second groove is provided inside the extension column (6), the second groove is connected to the first groove, and the first groove and the second groove form a T-shape.

5. The quick-install PT overvoltage suppression assembly according to claim 4 is characterized in that: A first magnetic block (11), the first magnetic block (11) being located inside the second groove and slidably connected to the extension column (6); A second magnetic block is embedded in the first positioning plate (12), and the first magnetic block (11) and the second magnetic block magnetically repel each other; A rotating shaft (7), the rotating shaft (7) being located inside the second groove, and the rotating shaft (7) being used to connect the first magnetic block (11) with the driving assembly; A limiting strip (10), the limiting strip (10) being located on the top of the first positioning plate (12) and fixedly connected to the first positioning plate (12), the limiting strip (10) being used to limit the movement of the first positioning plate (12).

6. The quick-install PT overvoltage suppression assembly according to claim 5, characterized in that: The drive assembly comprises: a threaded column (8), the threaded column (8) being located inside the rectangular groove (5) and being slidably connected to the primary harmonic elimination device (1), the threaded column (8) being located above the extension column (6) and being fixedly connected to the extension column (6), and the threaded column (8) being fixedly connected to the limit plate (3); A screw rod (4), the screw rod (4) being located inside the threaded column (8) and being threadedly connected to the threaded column (8), the screw rod (4) being used to control the extension column (6) and the threaded column (8) to move up and down, the screw rod (4) being rotationally connected to the rotating shaft (7), and the screw rod (4) being threadedly connected to the limiting plate (3).

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