Anti-interference device for harmonic balance of power grid

Abstract

The utility model discloses an anti-interference device for harmonic balance of a power grid, which belongs to the field of power grids and comprises a plurality of three-phase reactors connected in series, and each three-phase reactor comprises three iron cores, coils wound on the iron cores, iron yokes sleeved on two sides of the coils and fixing plates positioned on two sides of the three iron cores. Compared with the prior art, the device has the advantages that the change-over switch is installed on one side of the three-phase reactor, the positive electrode end of each coil is connected to the output port of each gear of the change-over switch through a wire, and the input end of a power grid is connected to the input port of the change-over switch; the number of the coils connected in series is adjusted by changing the gears of the change-over switch, so that the effective number of the coils connected in series is changed under the condition that the length of a wire is not changed.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of power grid, concretely refers to a power grid harmonic balance is with anti -interference device. BACKGROUND

[0002] In the power transmission of power grid, the current through the frequency converter or transformer will distort the alternating current and voltage when working, and generate a large number of harmonics; in order to weaken the influence of harmonics on electronic equipment, the corresponding power grid harmonic balance anti-interference device is installed in front of the frequency converter.

[0003] The existing power grid harmonic balance anti-interference device is mainly composed of a plurality of three-phase reactors connected in series, and then the filter behind the frequency converter can reduce the peak value of the output end harmonics, wherein different types of frequency converters require different numbers of three-phase reactors connected in series, wherein the three-phase reactor is mainly composed of three iron cores, coils wound on the iron cores, iron yokes sleeved on both sides of the coils, and fixing plates located on both sides of the three iron cores, wherein the fixing plate is fixedly connected with the iron core through the fastening bolt, and each coil is connected in series through the wire wound on the iron yoke.

[0004] Although this series connection can achieve the effect of series connection of three-phase reactor coils, if the frequency converter model is changed, the number of series connection of three-phase reactors needs to be changed, and during the changing process, the wire connection position of the output end needs to be changed, because the wire is usually cut to the appropriate length after connecting the output end, which makes it often necessary to connect additional wires when changing the connection position of the output end; and each three-phase reactor is not fixedly connected with the corresponding connecting structure when connected in series. UTILITY MODEL CONTENTS

[0005] The technical problem to be solved by the utility model is that the existing power grid harmonic balance anti-interference device cannot change the number of series connection of three-phase reactors without changing the length of the output end wire, and there is no corresponding fixing tool for connecting each three-phase reactor.

[0006] To solve the above technical problems, the technical scheme provided by the utility model is as follows: a power grid harmonic balance anti-interference device, comprising a plurality of three-phase reactors connected in series, the three-phase reactor comprising three iron cores, coils wound on the iron cores, iron yokes sleeved on both sides of the coils, and fixing plates located on both sides of the three iron cores, the fixing plate being connected with the iron core through the fastening bolt, and each coil being connected in series through the wire sleeved on the iron yoke,

[0007] The positive pole yoke of each coil is provided with a change-over switch connected by a wire, and the access end of the three-phase reactor is connected to the main switch of the change-over switch.

[0008] As an improvement, the conversion number of the change-over switch is greater than the maximum number of the coils in series.

[0009] As an improvement, the material of the insulating cover is magnetic isolation polyethylene.

[0010] As an improvement, the iron core penetrates the inner wall of the fixed plate, and the fastening bolt and the fixed plate are both insulating materials.

[0011] As an improvement, the convex strip is connected to the bottom surface of the concave groove through a plurality of positioning bolts.

[0012] As an improvement, one side of the yoke is provided with a wire screw of the wire.

[0013] The utility model has the advantages compared with the prior art:

[0014] 1. The device installs the change-over switch on one side of the three-phase reactor, connects the positive pole end of each coil to the output port of each gear of the change-over switch by a wire, and connects the input end of the power grid to the input port of the change-over switch, adjusts the number of coil series by changing the gear of the change-over switch, so as to change the effective number of series coils without changing the length of the wire.

[0015] 2. The insulating cover is installed at the outer end of the three-phase reactor to prevent electric leakage, then the concave groove is welded behind the insulating cover, the convex strip is inserted into the concave groove, and the position of each three-phase reactor is fixed by the sliding connection of the convex strip and the inner wall of the concave groove. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is a front side view of the total structure of the anti-interference device for power grid harmonic balance.

[0017] Figure 2 It is a rear side view of the total structure of the anti-interference device for power grid harmonic balance.

[0018] Figure 3 It is an explosion view of the three-phase reactor of the anti-interference device for power grid harmonic balance.

[0019] Figure 4 It is a connection sectional view of the concave groove and the convex strip of the anti-interference device for power grid harmonic balance.

[0020] Figure 5 is the three-phase reactor section view of the anti-interference device for power grid harmonic balance.

[0021] As shown in the drawings: 1, three-phase reactor; 11, core; 12, coil; 13, iron yoke; 131, wire screw; 14, fixed plate; 15, fastening bolt; 16, insulating cover; 17, concave groove; 18, convex bar; 19, positioning bolt; 2, change-over switch. DETAILED DESCRIPTION

[0022] The utility model makes further detailed description in combination with the drawings.

[0023] As shown in the drawings Figure 1 , 3 , 4, 5, including a plurality of series three-phase reactor 1, the existing three-phase reactor 1 includes three iron cores 11, the coil 12 wound on the iron core 11, the iron yoke 13 on both sides of the coil 12 and the fixed plate 14 on both sides of the three iron cores 11, in order to ensure the stability of the fixed plate 14 and the iron core 11 connection, the fixed plate 14 is connected with the iron core 11 by fastening bolt 15, and the iron core 11 passes through the inner wall of the fixed plate 14, in order to avoid electric leakage, wherein the fastening bolt 15 and the fixed plate 14 are all insulating materials.

[0024] The series connection mode of the coil is that each coil 12 is connected in series by the wire wrapped on the iron yoke 13, in order to ensure the stability of the wire connection, the iron yoke 13 is provided with wire screw 131 on one side of the wire, and the wire screw 131 passes through the iron yoke 13, in order to facilitate the effective series connection number of the coil 12, the positive iron yoke 13 of each coil 12 is provided with change-over switch 2 connected by wire, in order to avoid accidental power-on, the access end of the three-phase reactor 1 is connected to the main switch of the change-over switch 2, and the power needs to be turned off when rotating the change-over switch 2 to ensure safety, in order to avoid the situation that the change-over switch 2 gear is insufficient, when selecting the change-over switch 2, the conversion number of the change-over switch 2 is greater than the maximum number of the coil 12 connected in series.

[0025] As shown in the drawings Figure 2 , 4As shown in the drawings, in order to avoid the coil 12 of the multiple three-phase reactors 1 from accidental discharge, a shell 16 is arranged between the two fixing plates 14 and covers the outer wall end of the coil 12, and the shell 16 is made of magnetic isolation polyethylene, which can isolate electric arc and weaken the mutual influence of electromagnetic fields of the three-phase reactors 1, in order to facilitate the series connection of the multiple three-phase reactors 1, a concave groove 17 is welded on one side of the shell 16, the concave groove 17 is internally provided with a convex strip 18 which is in sliding connection with the inner wall of the concave groove 17, in order to fix the position of the three-phase reactor 1, the convex strip 18 is connected with the bottom surface of the concave groove 17 through a plurality of positioning bolts 19, and the positioning bolts 19 are equidistantly arranged.

[0026] In the specific implementation, before starting, the number of the coils 12 in the series three-phase reactors 1 is determined according to the model of the frequency converter, the number of the effective coils 12 is determined through the change-over switch 2, and then the power grid is started, when the effective power of the frequency converter needs to be changed, the power grid is disconnected, and after the frequency converter is replaced, the effective suppression of the harmonic can be completed by rotating the change-over switch 2 again, and it is noted that the change-over switch 2 needs to be turned to the off position before the frequency converter is replaced.

[0027] The above describes the utility model and its implementation mode, and the description is not restrictive, and the drawings only show one of the implementation modes of the utility model, and the actual structure is not limited thereto. In summary, if a person skilled in the art is inspired thereby, without departing from the creative purpose of the utility model, similar structural modes and embodiments can be designed without creativity, which should belong to the protection scope of the utility model.

Claims

1. An anti-interference device for power grid harmonic balancing, comprising a plurality of three-phase reactors (1) connected in series, wherein each three-phase reactor (1) comprises three iron cores (11), coils (12) wound on the iron cores (11), yokes (13) sleeved on both sides of the coils (12), and fixing plates (14) located on both sides of the three iron cores (11), wherein the fixing plates (14) are connected to the iron cores (11) by fastening bolts (15), and each coil (12) is connected in series by wires sleeved on the yokes (13), characterized in that: A changeover switch (2) is provided above the positive pole yoke (13) of each coil (12) and connected by a wire. The input end of the three-phase reactor (1) is connected to the main switch of the changeover switch (2). An insulating cover (16) is provided between the two fixed plates (14) and sleeved on the outer wall of the coil (12). A concave groove (17) is welded on one side of the insulating cover (16). A convex strip (18) is provided inside the concave groove (17) and slidably connected to the inner wall of the concave groove (17).

2. The anti-interference device for power grid harmonic balancing according to claim 1, characterized in that: The number of conversions of the changeover switch (2) is greater than the maximum number of coils (12) connected in series.

3. The anti-interference device for power grid harmonic balancing according to claim 1, characterized in that: The insulating cover (16) is made of magnetically shielded polyethylene.

4. The anti-interference device for power grid harmonic balancing according to claim 1, characterized in that: The iron core (11) passes through the inner wall of the fixing plate (14), and both the fastening bolt (15) and the fixing plate (14) are made of insulating material.

5. The anti-interference device for power grid harmonic balancing according to claim 1, characterized in that: The convex strip (18) is connected to the bottom surface of the concave groove (17) by a number of positioning bolts (19).

6. The anti-interference device for power grid harmonic balancing according to claim 1, characterized in that: One side of the yoke (13) is provided with a wire screw (131) for the wire.

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