Stator coil anti-corona structure with high rated voltage class

Abstract

The utility model relates to the technical field of motor insulation, and discloses a stator coil anti-corona structure with a high rated voltage grade, which comprises a main insulator, a coil, a low-resistance belt, a middle-resistance belt and a high-resistance belt, the coil is sequentially wrapped by the main insulator, the low-resistance belt, the middle-resistance belt and the high-resistance belt, and the stator coil anti-corona structure is characterized in that the middle-resistance belt is lapped on the low-resistance belt and is half-lapped, and the high-resistance belt is lapped on the middle-resistance belt. And the high stop band is lapped on the middle stop band and is semi-lapped. The device has the advantage of inhibiting corona generation.

Description

Technical Field

[0001] The utility model relates to the technical field of motor insulation, in particular to an anti-corona structure for a stator coil with a high rated voltage level. Background Art

[0002] The manufacturing of high-voltage motor coils is a very tedious task, which requires winding, molding, gelling, wrapping with mica tape, wrapping with high-resistance tape and low-resistance tape. Corona is a luminous discharge phenomenon caused by ionization of the air when the electric field strength near the coil surface exceeds a certain limit. Corona discharge will cause gradual corrosion of the main insulation and eventually lead to coil breakdown. Corona discharge in the coil slot can be prevented by wrapping the slot surface with a low-resistance semiconductor tape or applying low-resistance semiconductor paint. If no corresponding measures are taken at the coil end, a circle of corona will be formed at the end of the low-resistance layer due to the concentration of the electric field.

[0003] Chinese patent document CN104410191A discloses a high-voltage motor stator coil insulation structure, including a straight segment insulation part and a curved segment insulation part, characterized in that: the straight segment insulation part includes a first insulation layer formed by mixing and half-wrapping six layers of two mica tapes outside the straight segment of the coil body, and the first insulation layer is half-wrapped with a first low-resistance tape outside; the curved segment insulation part includes a second insulation layer formed by mixing and half-wrapping five layers of two mica tapes outside the curved segment of the coil body, and the second insulation layer is half-wrapped with a second low-resistance tape outside; the first and second low-resistance tapes are half-wrapped with high-resistance tapes outside, and the high-resistance tape is half-wrapped with an alkali-free glass ribbon outside.

[0004] Chinese patent document CN102447361A discloses a method for preparing the main insulation and anti-corona layer of a large high-voltage motor stator coil by one-time dip molding, wherein the structure of the stator coil is that a low-resistance anti-corona layer is half-lapped in the low-resistance range of the stator coil, and a medium-resistance anti-corona layer, a medium-high-resistance anti-corona layer and a high-resistance anti-corona layer are half-lapped in the medium-resistance, medium-high-resistance and high-resistance parts of the stator coil.

[0005] The prior art has the following disadvantages: the higher the operating voltage of the motor, the more serious the corona hazard, and thus the higher the requirement for anti-corona, and the existing stator coil is prone to corona. Utility Model Content

[0006] The utility model provides a high-rated voltage level stator coil anti-corona structure for suppressing the occurrence of corona, comprising a main insulation, a coil, a low resistance band, a medium resistance band and a high resistance band, wherein the main insulation, the low resistance band, the medium resistance band and the high resistance band are sequentially wrapped on the coil, and the utility model is characterized in that the medium resistance band is overlapped on the low resistance band and half-folded, and the high resistance band is overlapped on the medium resistance band and half-folded.

[0007] Preferably, the high-resistance tape comprises a first section of high-resistance tape and a second section of high-resistance tape, the first section of high-resistance tape overlaps the medium-resistance tape and half overlaps, the second section of high-resistance tape covers the first section of high-resistance tape and the medium-resistance tape, overlaps the low-resistance tape and half overlaps, and the overlap length of the second section of high-resistance tape is longer than the overlap length of the medium-resistance tape.

[0008] In order to prevent the high-resistance belt from being damaged, the bending part of the coil is the first section of the high-resistance belt, and the first section of the high-resistance belt is wrapped with an additional insulating belt to form a high-resistance end.

[0009] Furthermore, the medium-resistance tape and the first section of high-resistance tape are simultaneously covered with a flat-wrapped additional insulating tape.

[0010] Preferably, the additional insulating tape is a multi-resin mica tape.

[0011] Preferably, the end of the high-resistance belt is wrapped with a polyester fiber protective belt to the coil.

[0012] Preferably, a protective paint layer is provided on the outermost layer.

[0013] Preferably, the medium resistance belt and the low resistance belt overlap by 20-25 mm, and the half-fold is 60-80 mm long.

[0014] Preferably, the first section of high-resistance tape overlaps the medium-resistance tape by 20-25 mm, and the half-lap is 100-120 mm long.

[0015] Preferably, the second section of high resistance tape overlaps the low resistance tape by 30-40 mm, and the half-fold is 320-350 mm long.

[0016] The utility model has the following beneficial effects:

[0017] Compared with the conventional anti-corona structure, the utility model anti-corona structure adds multiple high-resistance anti-corona belts and multiple anti-corona overlaps, reduces the distribution of coil notch voltage and end voltage, effectively inhibits the occurrence of corona, and compared with the conventional anti-corona structure, corona occurs at a voltage of 19kv. The discharge phenomenon of the utility model can reach a maximum voltage of 35kv, weakening the electric field concentration and preventing the occurrence of corona discharge. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of an embodiment of the anti-corona structure of a stator coil with a high rated voltage level of the utility model;

[0019] Figure 2 Schematic diagram of the overlapping structure of low resistance band, medium resistance band and high resistance band. DETAILED DESCRIPTION

[0020] The following is further described in detail through specific implementation methods:

[0021] 1. Definition

[0022] Half-overlap means that half of the winding is overlapped.

[0023] 2. The reference numerals in the drawings of the specification include: main insulation 1, conductor 2, low resistance band 3, medium resistance band 4, high resistance band 5, first section of high resistance band 501, second section of high resistance band 502, additional insulation band 6, and protective paint layer 7.

[0024] Example 1

[0025] like Figure 1-2 As shown, a high-rated voltage level stator coil anti-corona structure for suppressing the occurrence of corona includes a main insulation 1, a conductor 2, a low-resistance band 3, a medium-resistance band 4 and a high-resistance band 5, the main insulation 1, the low-resistance band 3, the medium-resistance band 4 and the high-resistance band 5 are wrapped around the conductor 2 in sequence, the medium-resistance band 4 is overlapped on the low-resistance band 3 and half-overlapped, and the high-resistance band 5 is overlapped on the medium-resistance band 4 and half-overlapped.

[0026] The high-resistance tape 5 includes a first section of high-resistance tape 501 and a second section of high-resistance tape 502. The first section of high-resistance tape 501 is overlapped on the medium-resistance tape 4 and half-overlapped. The second section of high-resistance tape 502 covers the first section of high-resistance tape 501 and the medium-resistance tape 4 and is overlapped on the low-resistance tape 3 and half-overlapped. The overlap length of the second section of high-resistance tape 502 is longer than the overlap length of the medium-resistance tape 4.

[0027] The bending part of the conductor 2 is the first section of high resistance tape 501 , and the medium resistance tape 4 and the first section of high resistance tape 501 are simultaneously covered with a layer of flat-wrapped additional insulating tape 6 , and the additional insulating tape 6 is a multi-resin mica tape.

[0028] The end of the second section of high resistance tape 502 is wrapped with a polyester fiber protective tape to the coil, and the outermost layers of the low resistance tape 3 , the medium resistance tape 4 and the high resistance tape 5 are provided with a protective paint layer 7 .

[0029] The medium resistance belt 4 overlaps the low resistance belt 3 by 22mm, and the half-lap is 65mm long. The high resistance belt 5 includes a first section of high resistance belt 501 and a second section of high resistance belt 502. The first section of high resistance belt 501 overlaps the medium resistance belt 4 by 23mm, and the half-lap is 110mm long. The second section of high resistance belt 502 covers the first section of high resistance belt 501 and the medium resistance belt 4. The second section of high resistance belt 502 overlaps the low resistance belt 3 by 35mm, and the half-lap is 330mm. There is a discharge phenomenon at 35kv.

[0030] The above is only an embodiment of the utility model. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the utility model before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for the technicians in this field, without departing from the structure of the utility model, several deformations and improvements can be made, which should also be regarded as the protection scope of the utility model, which will not affect the effect of the implementation of the utility model and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to explain the content of the claims.

Claims

1. A high-rated voltage stator coil anti-corona structure, comprising a main insulation (1), a conductor (2), a low-resistance band (3), a medium-resistance band (4) and a high-resistance band (5), wherein the main insulation (1), the low-resistance band (3), the medium-resistance band (4) and the high-resistance band (5) are sequentially wrapped around the conductor (2), characterized in that: The medium resistance band (4) is overlapped on the low resistance band (3) and half-wrapped, and the high resistance band (5) is overlapped on the medium resistance band (4) and half-wrapped.

2. The high rated voltage stator coil anti-corona structure according to claim 1, characterized in that: The high resistance tape (5) comprises a first section of high resistance tape (501) and a second section of high resistance tape (502), wherein the first section of high resistance tape (501) is overlapped on the medium resistance tape (4) and half-overlapped, and the second section of high resistance tape (502) covers the first section of high resistance tape (501) and the medium resistance tape (4) and is overlapped on the low resistance tape (3) and half-overlapped, and the overlap length of the second section of high resistance tape (502) is longer than the overlap length of the medium resistance tape (4).

3. The anti-corona structure of the stator coil with high rated voltage level according to claim 2 is characterized in that: The bending part of the conductive wire (2) is the first section of high-resistance tape (501), and the first section of high-resistance tape (501) is wrapped with an additional insulating tape (6) to form a high-resistance end.

4. The anti-corona structure for stator coils with high rated voltage level according to claim 2, characterized in that: The medium resistance tape (4) and the first section of high resistance tape (501) are simultaneously covered with a layer of flat-wrapped additional insulating tape (6).

5. The anti-corona structure for stator coils with high rated voltage level according to claim 3 or 4, characterized in that: The additional insulating tape (6) is a multi-resin mica tape.

6. The anti-corona structure for stator coils with high rated voltage level according to any one of claims 2 to 4, characterized in that: The end of the high resistance tape (5) is wrapped with a polyester fiber protective tape to the coil.

7. The high rated voltage stator coil anti-corona structure according to claim 6, characterized in that: The outermost layer is provided with a protective paint layer (7).

8. The anti-corona structure for stator coils with high rated voltage level according to any one of claims 2, 3, 4 and 7, characterized in that: The medium resistance band (4) overlaps the low resistance band (3) by 20-25 mm, and the half-fold is 60-80 mm long.

9. The anti-corona structure for stator coils with high rated voltage level according to any one of claims 2, 3, 4 and 7, characterized in that: The first section of high resistance tape (501) overlaps the medium resistance tape (4) by 20-25 mm, and the half-lap is 100-120 mm long.

10. The anti-corona structure for stator coils with high rated voltage level according to any one of claims 2, 3, 4 and 7, characterized in that: The second section of high resistance tape (502) overlaps the low resistance tape (3) by 30-40 mm, and the half-fold is 320-350 mm long.

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