Assembly type power grid harmonic detection filter

Abstract

The invention relates to the technical field of filters, and discloses an assembly type power grid harmonic detection filter which comprises a bottom plate, a protection mechanism and a fixed limiting mechanism are arranged above the bottom plate, the protection mechanism comprises a protection shell, the back face of the protection shell is fixedly connected with a hinge, and the front face of the hinge is fixedly connected with a protection top cover. A clamping block is clamped into the protective shell, and a sliding plate is slidably connected into the protective shell. According to the assembly type power grid harmonic detection filter, through mutual cooperation of the fixed base, the first clamping groove, the second clamping groove, the fixed frame, the threaded rod and the lower pressing plate, the filter installation module can be conveniently assembled, and the situation that when a certain assembly in the filter breaks down, the whole filter needs to be overhauled on a large scale is avoided; the whole filter is replaced and maintained, and corresponding harmonic detection and filtering modules cannot be added, so that the harmonic detection precision is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of filters, and in particular to an assembled power grid harmonic detection filter. Background Art

[0002] A filter is a filter circuit composed of capacitors, inductors and resistors. The filter can effectively filter out a specific frequency point in the power line or frequencies other than the frequency point to obtain a power signal of a specific frequency, or eliminate a power signal after a specific frequency. With the continuous development of new energy power generation such as solar photovoltaic power generation and wind power generation, these new energy power generation systems will also generate harmonics when connected to the power grid.

[0003] At present, today's filter equipment is often integrated and directly installed on the device that needs to be detected for harmonics. When a component in the filter fails, the entire filter will need to be overhauled on a large scale. The entire filter needs to be replaced and repaired, which consumes a lot of manpower and material resources and reduces the efficiency of harmonic detection. In addition, as the factory adds new large-scale power electronic equipment and generates new harmonic frequencies, it is impossible to add corresponding harmonic detection and filtering modules, resulting in reduced harmonic detection accuracy. Summary of the invention

[0004] The object of the present invention is to provide an assembled power grid harmonic detection filter to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: an assembled power grid harmonic detection filter, comprising a bottom plate, and a protection mechanism and a fixed limit mechanism are respectively arranged above the bottom plate; The protection mechanism comprises a protection shell, a hinge is fixedly connected to the back of the protection shell, a protection top cover is fixedly connected to the front of the hinge, a card block is clamped inside the protection shell, a sliding plate is slidably connected to the inside of the protection shell, a button and a limit column are fixedly connected to the front of the sliding plate, a spring is fixedly connected to the back of the sliding plate, the outer surface of the limit column contacts the inner wall of the card block, two dustproof filter plates and two ventilation ducts are fixedly connected to the inner wall of each of the ventilation ducts, two filter screen plates are fixedly connected to the inner wall of each ventilation duct, and two fan blades are fixedly connected to one end of each group of filter screen plates away from each other; The fixed limiting mechanism comprises a fixed base, the upper surface of the fixed base is fixedly connected with four fixing frames, the inner wall of each group of the fixing frames is threadedly connected with two threaded rods, the outer surface of each group of the threaded rods is fixedly connected with two bearings, the bottom end of each group of the bearings is fixedly connected with two lower pressure plates, and the bottom surface of each group of the lower pressure plates is fixedly connected with six limiting blocks, the upper surface of the fixed base is respectively provided with a plurality of identical first card slots and a plurality of identical second card slots, wherein the interiors of three of the first card slots are carded with filter installation modules, the outer surface of each filter installation module is fixedly connected with two fixing plates, the upper surface of each group of the fixing plates is provided with two grooves, the inner wall of each filter installation module is fixedly connected with four capacitor element bodies, three inductor element bodies and four resistor element bodies, the outer surface of the fixed base is fixedly connected with four first connecting terminals, the outer surface of each filter installation module is fixedly connected with two second connecting terminals, the inner wall of each group of the grooves is in contact with the outer surface of the limiting block, and the outer surface of each group of the second connecting terminals is in contact with the inner wall of the second card slot.

[0006] Preferably, two rain shields are fixedly connected to the outer surface of the protective shell, and the sides of the two rain shields that are close to each other are fixedly connected to the sides of the two dust filter plates that are away from each other.

[0007] Preferably, the outer surface of each of the rain shields is fixedly connected to two support frames, and the side surfaces of each group of support frames close to each other are fixedly connected to the outer surface of the protective shell.

[0008] Preferably, the inner wall of each group of the support frames is threadedly connected with four fixing bolts, and the outer surface of each group of the fixing bolts is threadedly connected to the inner wall of the rain shield.

[0009] Preferably, the inner wall of each hinge is threadedly connected with four reinforcing bolts, wherein the outer surfaces of two groups of the reinforcing bolts are threadedly connected to the inner wall of the protective top cover, and the outer surfaces of the other two groups of the reinforcing bolts are threadedly connected to the inner wall of the protective outer shell.

[0010] Preferably, two fixing rings are fixedly connected to the outer surface of each group of the first connecting terminals, and one end of each group of the fixing rings close to each other is fixedly connected to the outer surface of the fixing base.

[0011] Preferably, four reinforcement blocks are fixedly connected to the outer surface of each group of the fixing plates, and one side surface of each group of the reinforcement blocks close to each other is fixedly connected to the outer surface of the filter mounting module.

[0012] Preferably, four limiting frames are fixedly connected to the upper surface of each group of the fixing plates, and a side surface of each group of the limiting frames close to each other is fixedly connected to the outer surface of the filter mounting module.

[0013] Preferably, the inner wall of each group of the limiting frames is threadedly connected with four fastening bolts, and the outer surface of each group of fastening bolts is threadedly connected to the inner wall of the fixing plate.

[0014] Preferably, two limiting rings are fixedly connected to the outer surface of the spring, wherein one of the limiting rings is fixedly connected to the back of the sliding plate at one end close to the button, and the other limiting ring is fixedly connected to the inner wall of the protective shell at one end away from the sliding plate.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are: The present invention is provided with buttons, sliding plates, limit columns, blocks, springs and hinges that cooperate with each other, so that the protective top cover can be opened and closed conveniently, which plays a convenient and quick role, enhances the use effect of the device, and is convenient for staff to detect the filter detection device at any time. The electrical components inside the protective shell can be ventilated and cooled through the rain shield, dust filter plate, ventilation duct and fan blades to prevent the internal temperature of the device from being high, resulting in a problem of reduced service life. The filter installation module can be assembled conveniently by providing a fixed base, a first card slot, a second card slot, a fixed frame, a threaded rod and a lower pressure plate that cooperate with each other, so as to achieve the purpose of easy assembly and enhance the applicability of the device. The position of the filter installation module can be fixed and limited by the groove and the limit block, so as to enhance the stability of the device. It can effectively avoid the need to perform large-scale overhaul of the entire filter when a component in the filter fails, replace and repair the entire filter, consume a lot of manpower and material resources, reduce the efficiency of harmonic detection, and as the factory adds new large-scale power electronic equipment and generates new harmonic frequencies, it is impossible to add corresponding harmonic detection and filtering modules, resulting in the problem of reduced accuracy of harmonic detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall three-dimensional structure of the assembled power grid harmonic detection filter of the present invention; Figure 2 It is a schematic diagram of the structure of the protective top cover of the present invention; Figure 3 It is a structural schematic diagram of the threaded rod of the present invention; Figure 4 It is a structural schematic diagram of the fixing frame of the present invention; Figure 5 It is a schematic diagram of the structure of the fan blade of the present invention; Figure 6 It is a structural schematic diagram of the first card slot of the present invention; Figure 7 It is a structural schematic diagram of the lower pressing plate of the present invention; Figure 8It is a structural schematic diagram of the fixing plate of the present invention; Fig. 9 is a schematic structural diagram of a second connecting terminal of the present invention; Fig.10 It is a schematic structural diagram of the sliding plate of the present invention.

[0017] Among them: 1. bottom plate; 2. protection mechanism; 201. protective shell; 202. protective top cover; 203. button; 204. hinge; 205. dust filter plate; 206. ventilation duct; 207. block; 208. filter screen; 209. fan blade; 210. sliding plate; 211. limit column; 212. spring; 3. fixed limit mechanism; 301. fixed base; 302. fixed frame; 303. threaded rod; 304. first connecting terminal; 305. filter Device installation module; 306, lower pressure plate; 307, limit block; 308, fixing plate; 309, second connecting terminal; 310, first slot; 311, second slot; 312, bearing; 313, groove; 314, capacitor element body; 315, inductor element body; 316, resistor element body; 4, rain shield; 5, fixing ring; 6, fixing bolt; 7, support frame; 8, reinforcement bolt; 9, reinforcement block; 10, limit frame; 11, tightening bolt; 12, limit ring. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Embodiment 1

[0019] See also Figure 1-10, an assembled power grid harmonic detection filter, comprising a bottom plate 1, a protection mechanism 2 and a fixed limit mechanism 3 are respectively arranged above the bottom plate 1, the protection mechanism 2 comprises a protective shell 201, a hinge 204 is fixedly connected to the back of the protective shell 201, a protective top cover 202 is fixedly connected to the front of the hinge 204, a card block 207 is clamped inside the protective shell 201, a sliding plate 210 is slidably connected to the inside of the protective shell 201, a button 203 and a limit column 211 are fixedly connected to the front of the sliding plate 210, a spring 212 is fixedly connected to the back of the sliding plate 210, the outer surface of the limit column 211 contacts the inner wall of the card block 207, two dustproof filter plates 205 and two ventilation ducts 206 are fixedly connected to the inner wall of each ventilation duct 206, two filter screen plates 208 are fixedly connected to the inner wall of each ventilation duct 206, and two fan blades 209 are fixedly connected to the ends of each group of filter screen plates 208 away from each other; The outer surface of the protective housing 201 is fixedly connected with two rain shields 4, and the sides of the two rain shields 4 close to each other are fixedly connected with the sides of the two dust filter plates 205 away from each other. The rain shields 4 can prevent external rainwater from entering the interior of the protective housing 201, thereby avoiding damage to the electrical components inside the housing; The outer surface of each rain shield 4 is fixedly connected to two support frames 7, and the side of each group of support frames 7 close to each other is fixedly connected to the outer surface of the protective shell 201. The support frames 7 can be used to fix and support the rain shield 4 on the protective shell 201, thereby enhancing the stability of the device and preventing it from shaking during use; The inner wall of each set of support frames 7 is threadedly connected with four fixing bolts 6, and the outer surface of each set of fixing bolts 6 is threadedly connected with the inner wall of the rain shield 4. The fixing bolts 6 can fix the support frame 7 and the rain shield 4, effectively preventing them from deflecting and becoming unstable during operation; The inner wall of each hinge 204 is threadedly connected with four reinforcing bolts 8, wherein the outer surfaces of two groups of reinforcing bolts 8 are threadedly connected to the inner wall of the protective top cover 202, and the outer surfaces of the other two groups of reinforcing bolts 8 are threadedly connected to the inner wall of the protective shell 201. The reinforcing bolts 8 can reinforce the hinge 204, the protective shell 201 and the protective top cover 202, and have a strong fixing and limiting effect, thereby avoiding the problem of position displacement during use; Two limiting rings 12 are fixedly connected to the outer surface of the spring 212, wherein one end of one limiting ring 12 close to the button 203 is fixedly connected to the back side of the sliding plate 210, and the other end of the limiting ring 12 away from the sliding plate 210 is fixedly connected to the inner wall of the protective shell 201. The limiting ring 12 can be used to limit the position of the spring 212 to prevent the problem of position displacement and instability during use.

[0020] The specific implementation method of this embodiment is: first, the sliding plate 210 is moved by pressing the button 203, and then the limiting column 211 is driven to move, so that the limiting column 211 can no longer limit the position of the block 207, and then the protective top cover 202 can be opened, thereby making it convenient to assemble the electrical components inside the protective shell 201, enhancing the applicability of the device and facilitating assembly. When the electrical components inside the protective shell 201 generate a higher temperature, by making the two fan blades 209 rotate in the same direction, the inside of the protective shell 201 can be ventilated and dissipated, thereby enhancing the use effect of the device and effectively avoiding the problem of high temperature inside the device, which leads to a reduction in its service life. Embodiment 2

[0021] See also Figure 1-10 The fixed limiting mechanism 3 includes a fixed base 301, and the upper surface of the fixed base 301 is fixedly connected with four fixing frames 302, and the inner wall of each group of fixing frames 302 is threadedly connected with two threaded rods 303, and the outer surface of each group of threaded rods 303 is fixedly connected with two bearings 312, and the bottom end of each group of bearings 312 is fixedly connected with two lower pressure plates 306, and the bottom surface of each group of lower pressure plates 306 is fixedly connected with six limiting blocks 307, and the upper surface of the fixed base 301 is respectively provided with a plurality of identical first card slots 310 and a plurality of identical second card slots 311, wherein the interior of the three first card slots 310 is carded with a filter installation module 305, and each filter installation The outer surface of the installation module 305 is fixedly connected to two fixing plates 308, and the upper surface of each group of fixing plates 308 is provided with two grooves 313. The inner wall of each filter installation module 305 is fixedly connected to four capacitor element bodies 314, three inductor element bodies 315 and four resistor element bodies 316. The outer surface of the fixed base 301 is fixedly connected to four first connection terminals 304. The outer surface of each filter installation module 305 is fixedly connected to two second connection terminals 309. The inner wall of each group of grooves 313 is in contact with the outer surface of the limit block 307, and the outer surface of each group of second connection terminals 309 is in contact with the inner wall of the second slot 311. Two fixing rings 5 ​​are fixedly connected to the outer surface of each group of first connection terminals 304, and one end of each group of fixing rings 5 ​​close to each other is fixedly connected to the outer surface of the fixing base 301. The fixing rings 5 ​​can fix the first connection terminals 304 and the fixing base 301 to prevent their positions from shaking and shifting; Four reinforcing blocks 9 are fixedly connected to the outer surface of each set of fixing plates 308, and the side surfaces of each set of reinforcing blocks 9 close to each other are fixedly connected to the outer surface of the filter installation module 305. The reinforcing blocks 9 can reinforce the fixing plates 308 and the filter installation module 305, play a strong fixing role, and prevent their positions from moving; Four limiting frames 10 are fixedly connected to the upper surface of each set of fixing plates 308, and the side surfaces of each set of limiting frames 10 close to each other are fixedly connected to the outer surface of the filter installation module 305. The limiting frames 10 can limit the position of the fixing plates 308 to prevent them from shaking during use; The inner wall of each set of limit frames 10 is threadedly connected with four fastening bolts 11, and the outer surface of each set of fastening bolts 11 is threadedly connected to the inner wall of the fixing plate 308. The fastening bolts 11 can reinforce the limit frames 10 and the fixing plate 308 to avoid sliding and deflection during use.

[0022] The specific implementation of this embodiment is as follows: first, the filter installation module 305 is installed in the first slot 310 on the fixed base 301, and then the second connection terminal 309 is installed in the second slot 311. The bearing 312 is driven to move downward by rotating the threaded rod 303, and then the lower pressure plate 306 is driven to move downward, and then the limit block 307 is driven to move downward, so that the limit block 307 can be clamped in the groove 313 on the fixed plate 308, thereby fixing and limiting the position of the filter installation module 305, effectively preventing the problem of its position offset and instability during operation. The various components of the assembled filter are pre-made in the factory. When installing on site, it only needs to be simply assembled according to the design drawings, and by installing the capacitor element body 314, the inductor element body 315 and the resistor element body 316 of the filter in an independent filter installation module 305, these filter installation modules 305 have standard interfaces and are installed in places such as power grid substations. During installation, workers can quickly combine the modules together by connecting these interfaces, which greatly shortens the installation time. Compared with traditional filters that require complex wiring and component installation on site, the efficiency is significantly improved. When a component in the device fails, only the failed filter installation module 305 needs to be replaced and repaired, which is convenient for maintenance personnel to carry out maintenance and replacement work, and there is no need to perform large-scale inspections on the entire filter. When the scale of the power grid is expanded or the harmonic situation changes and the filtering function needs to be increased, a new filter installation module 305 can be easily added to meet the needs. This can effectively avoid the need for large-scale inspections of the entire filter when a component in the filter fails. The entire filter needs to be replaced and repaired, which consumes a lot of manpower and material resources and reduces the efficiency of harmonic detection. As the factory adds new large-scale power electronic equipment and generates new harmonic frequencies, it is impossible to add corresponding harmonic detection and filtering modules, resulting in reduced harmonic detection accuracy. Embodiment 3

[0023] See also Figure 1-10The specific implementation of this embodiment is as follows: first, the sliding plate 210 is moved by pressing the button 203, and then the limiting column 211 is driven to move, so that the limiting column 211 no longer limits the position of the block 207, and then the protective top cover 202 can be opened, thereby facilitating the assembly of the electrical components inside the protective shell 201, enhancing the applicability of the device and facilitating assembly. When the electrical components inside the protective shell 201 generate a high temperature, the two fan blades 209 are rotated in the same direction to ventilate and dissipate heat inside the protective shell 201, thereby enhancing the use effect of the device and effectively avoiding the high temperature inside the device. The problem of high, resulting in a reduced service life, the filter installation module 305 is installed in the first slot 310 on the fixed base 301, and then the second connecting terminal 309 is installed in the second slot 311, and the bearing 312 is driven to move downward by rotating the threaded rod 303, and then the lower pressure plate 306 is driven to move downward, and then the limit block 307 is driven to move downward, so that the limit block 307 can be clamped in the groove 313 on the fixed plate 308, thereby fixing and limiting the position of the filter installation module 305, effectively preventing the problem of its position being offset and unstable during operation. The various components of the assembled filter are pre-made in the factory Completed, when installing on site, only simple assembly is required according to the design drawings, and by installing the capacitor element body 314, the inductor element body 315 and the resistor element body 316 of the filter in independent filter installation modules 305, these filter installation modules 305 have standard interfaces. When installing in places such as power grid substations, workers can quickly combine the modules together by connecting these interfaces, which greatly shortens the installation time. Compared with traditional filters that require complex wiring and component installation on site, the efficiency is significantly improved. When a component in the device fails, only the failed filter installation module 305 needs to be replaced It only needs maintenance, which is convenient for maintenance personnel to carry out maintenance and replacement work, and there is no need to carry out large-scale overhaul of the entire filter. When the scale of the power grid is expanded or the harmonic situation changes and it is necessary to increase the filtering function, a new filter installation module 305 can be easily added to meet the demand. It can effectively avoid the need for large-scale overhaul of the entire filter when a component in the filter fails. The entire filter needs to be replaced and repaired, which consumes a lot of manpower and material resources and reduces the efficiency of harmonic detection. Moreover, as the factory adds new large-scale power electronic equipment and generates new harmonic frequencies, it is impossible to add corresponding harmonic detection and filtering modules, resulting in reduced accuracy of harmonic detection.

[0024] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0025] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An assembled power grid harmonic detection filter, comprising a base plate (1), characterized in that: A protection mechanism (2) and a fixed limiting mechanism (3) are respectively arranged above the bottom plate (1); The protection mechanism (2) comprises a protection shell (201), the back of the protection shell (201) is fixedly connected to a hinge (204), the front of the hinge (204) is fixedly connected to a protection top cover (202), the interior of the protection shell (201) is clamped with a clamping block (207), the interior of the protection shell (201) is slidably connected to a sliding plate (210), the front of the sliding plate (210) is fixedly connected to a button (203) and a limiting column (211), and the The back of the sliding plate (210) is fixedly connected to a spring (212); the outer surface of the limiting column (211) contacts the inner wall of the block (207); the inner wall of the protective housing (201) is fixedly connected to two dustproof filter plates (205) and two ventilation ducts (206); the inner wall of each ventilation duct (206) is fixedly connected to two filter screen plates (208); and each group of filter screen plates (208) is fixedly connected to two fan blades (209) at one end away from each other; The fixed limiting mechanism (3) comprises a fixed base (301), the upper surface of the fixed base (301) is fixedly connected to four fixing frames (302), the inner wall of each group of the fixing frames (302) is threadedly connected to two threaded rods (303), the outer surface of each group of the threaded rods (303) is fixedly connected to two bearings (312), the bottom end of each group of the bearings (312) is fixedly connected to two lower pressure plates (306), the bottom surface of each group of the lower pressure plates (306) is fixedly connected to six limiting blocks (307), and the upper surface of the fixed base (301) is respectively provided with a plurality of identical first card slots (310) and a plurality of identical second card slots (311), wherein the interiors of three of the first card slots (310) are carded with a filter installation module (305), and each of the filter The outer surface of the filter installation module (305) is fixedly connected to two fixing plates (308), the upper surface of each group of the fixing plates (308) is provided with two grooves (313), the inner wall of each filter installation module (305) is fixedly connected to four capacitor element bodies (314), three inductor element bodies (315) and four resistor element bodies (316), the outer surface of the fixed base (301) is fixedly connected to four first connection terminals (304), the outer surface of each filter installation module (305) is fixedly connected to two second connection terminals (309), the inner wall of each group of the grooves (313) is in contact with the outer surface of the limit block (307), and the outer surface of each group of the second connection terminals (309) is in contact with the inner wall of the second slot (311).

2. The assembled power grid harmonic detection filter according to claim 1, characterized in that: Two rain shields (4) are fixedly connected to the outer surface of the protective shell (201), and the sides of the two rain shields (4) that are close to each other are fixedly connected to the sides of the two dustproof filter plates (205) that are far away from each other.

3. The assembled power grid harmonic detection filter according to claim 2, characterized in that: The outer surface of each rain shield (4) is fixedly connected to two support frames (7), and the side surfaces of each group of support frames (7) that are close to each other are fixedly connected to the outer surface of the protective shell (201).

4. The assembled power grid harmonic detection filter according to claim 3, characterized in that: The inner wall of each group of the support frames (7) is threadedly connected with four fixing bolts (6), and the outer surface of each group of the fixing bolts (6) is threadedly connected to the inner wall of the rain shield (4).

5. The assembled power grid harmonic detection filter according to claim 1, characterized in that: The inner wall of each hinge (204) is threadedly connected to four reinforcing bolts (8), wherein the outer surfaces of two groups of the reinforcing bolts (8) are threadedly connected to the inner wall of the protective top cover (202), and the outer surfaces of the other two groups of the reinforcing bolts (8) are threadedly connected to the inner wall of the protective outer shell (201).

6. The assembled power grid harmonic detection filter according to claim 1, characterized in that: The outer surface of each group of the first connection terminals (304) is fixedly connected to two fixing rings (5), and one end of each group of the fixing rings (5) close to each other is fixedly connected to the outer surface of the fixing base (301).

7. The assembled power grid harmonic detection filter according to claim 1, characterized in that: Four reinforcement blocks (9) are fixedly connected to the outer surface of each group of the fixing plates (308), and a side surface of each group of the reinforcement blocks (9) close to each other is fixedly connected to the outer surface of the filter installation module (305).

8. The assembled power grid harmonic detection filter according to claim 1, characterized in that: Four limiting frames (10) are fixedly connected to the upper surface of each group of the fixing plates (308), and a side surface of each group of the limiting frames (10) close to each other is fixedly connected to the outer surface of the filter installation module (305).

9. The assembled power grid harmonic detection filter according to claim 8, characterized in that: The inner wall of each set of the limiting frames (10) is threadedly connected with four fastening bolts (11), and the outer surface of each set of fastening bolts (11) is threadedly connected to the inner wall of the fixing plate (308).

10. The assembled power grid harmonic detection filter according to claim 1, characterized in that: Two limiting rings (12) are fixedly connected to the outer surface of the spring (212), wherein one end of the limiting ring (12) close to the button (203) is fixedly connected to the back side of the sliding plate (210), and the other end of the limiting ring (12) away from the sliding plate (210) is fixedly connected to the inner wall of the protective housing (201).

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