Seamlessly spliced turn-to-turn insulation structure of generator

Abstract

The invention provides a seamlessly spliced turn-to-turn insulation structure of a generator, and relates to the field of rotor insulation protection. A seamlessly spliced turn-to-turn insulation structure of a generator comprises two insulation layers wrapping the outer side of a rotor coil, the two insulation layers comprise an inner insulation layer wrapping the outer side of the rotor coil and an outer insulation layer wrapping the outer side of the inner insulation layer, and connecting ports of the inner insulation layer and the outer insulation layer are arranged in a staggered mode. A covering layer is arranged between the inner insulating layer and the outer insulating layer, and the connecting port of the inner insulating layer and the connecting port of the outer insulating layer are both overlapped with the covering layer. According to the seamlessly spliced turn-to-turn insulation structure of the generator, the inner insulation layer and the outer insulation layer are independently spliced, and the insulation covering layer is arranged at the staggered connection port of the insulation layers at the two sides, so that the possibility of insulation failure caused by contact of copper cuttings, dust and the like at a gap can be reduced.

Description

Technical Field

[0001] The invention relates to the field of rotor insulation protection, in particular to a seamlessly spliced ​​inter-turn insulation structure of a generator. Background Art

[0002] The motor was subjected to rotor RSO test and the waveform was found to be significantly different from the normal waveform. The rotor end coil was inspected by endoscope and combined with the analysis of the generator excitation current, it was determined that there was a problem with the inter-turn insulation;

[0003] The conventional inter-turn insulation of the existing generator rotor is to use a single-layer inter-turn insulation of the entire length in the straight part of the rotor coil, and then flat-join the single-layer inter-turn insulation of the arc part at the end with the straight inter-turn insulation, and bond the inter-turn insulation to the rotor copper bar with an adhesive. Considering the coil height, the adjacent inter-turn insulation at the joint is not allowed to overlap, and direct splicing will inevitably produce joints. During the operation of the unit, oil mist and oil vapor carry copper chips, dust, etc. into the rotor through the air path and accumulate at the inter-turn insulation joint position, causing the insulation performance at this position to deteriorate and heat up, and eventually causing the inter-turn insulation in this area to break down and form an inter-turn short circuit fault.

[0004] The existing patent CN106571707B discloses a seamless splicing structure of inter-turn insulation of a generator rotor coil, comprising a single-layer inter-turn insulation bonded to the straight part of the rotor coil and a double-layer inter-turn insulation bonded to the arc area at the end of the rotor coil; the upper layer of the single-layer inter-turn insulation is peeled off along the thickness direction at the set range at both ends, leaving the bottom layer; the double-layer inter-turn insulation is composed of upper and lower layers of inter-turn insulation, the main part of the upper layer of inter-turn insulation is bonded to the lower layer of inter-turn insulation, and the end of the upper layer of inter-turn insulation is bonded to the bottom layer left at the end of the single-layer inter-turn insulation; the single-layer inter-turn insulation, the upper layer of inter-turn insulation, and the lower layer of inter-turn insulation are closely matched with each other to form a seamless splicing.

[0005] This technical solution achieves seamless splicing by staggering the joints of the upper and lower layers of the double-layer inter-turn insulation and the inter-turn insulation at the end of the straight line part at the arc part of the rotor coil end, thereby improving the insulation performance of the rotor coil inter-turn insulation and providing reliable protection for the safe operation of the rotor. This technical solution adopts the method of setting the splicing gap in the arc section. Since the straight line section will be insulated from the core part, the insulation requirements of the arc section are higher than those of the straight line section. Although the joints are staggered, the spacing is close and there is still oil mist, oil vapor entrained copper chips, and dust piled up at the joints, resulting in reduced insulation capacity. Summary of the invention

[0006] In view of the deficiencies of the prior art, the present invention provides a generator seamlessly spliced ​​inter-turn insulation structure, which solves the problem in the above background technology that the double-layer staggered seams set in the arc section easily lead to a decrease in insulation capacity.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: a seamless inter-turn insulation structure of a generator, comprising two insulating layers wrapped around the outside of a rotor coil, the two insulating layers being divided into an inner insulating layer wrapped around the outside of the rotor coil and an outer insulating layer wrapped around the outside of the inner insulating layer, the connection ports of the inner insulating layer and the outer insulating layer being staggered, a covering layer being arranged between the inner insulating layer and the outer insulating layer, and the connection ports of the inner insulating layer and the outer insulating layer both overlapping with the covering layer.

[0008] Preferably, the covering layer wraps the arc segment of the rotor coil and extends to the straight segment of the rotor coil, and the connecting port of the inner insulating layer and the connecting port of the outer insulating layer are both located in the straight segment of the rotor coil.

[0009] Preferably, the covering layer is made of insulating material, adhesive is coated on both sides of the covering layer, and protective layers for protecting the adhesive are arranged on both sides of the covering layer.

[0010] Preferably, the inner insulating layer and the outer insulating layer have the same width, and the gap distance between the inner insulating layer connection port and the outer insulating layer connection port is at least five times the width of the inner insulating layer.

[0011] Preferably, the inner insulating layer and the outer insulating layer have the same thickness, and the covering layer has a thickness smaller than that of the inner insulating layer.

[0012] Preferably, the outer surface of the same group of rotor coils is covered with a plurality of inner insulating layers, and the covering layer covers the outer surface of the connection between two adjacent inner insulating layers.

[0013] Preferably, the insulating layer connection openings covered on the outer surfaces of two adjacent groups of rotor coils are staggered, and the insulating layer connection openings covered on the outer surfaces of three consecutive rotor coils are arranged consecutively in three positions: top, middle and bottom.

[0014] Preferably, the bonding of the insulating layer comprises the following steps:

[0015] Step 1, applying adhesive to the outer surface of the rotor coil;

[0016] Step 2: Include and bond the inner insulating layer to the outer surface of the rotor coil, remove the inner protective layer of the cover layer, and cover the inner insulating layer connection port;

[0017] Step 3: Remove the outer protective layer of the covering layer, and apply adhesive on the surface of the inner insulating layer and the covering layer;

[0018] Step 4: Cover the outer surfaces of the inner insulating layer and the covering layer with an outer insulating layer, and ensure that the connection port of the outer insulating layer is located at the covering layer.

[0019] Preferably, the second step of bonding the insulating layer also includes bonding multiple inner insulating layers into a whole inner insulating layer through a covering layer, and making the single inner insulating layer completely wrap the arc segment of the rotor coil, and the covering layer is located on the straight segment of the rotor coil.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The generator has a seamless inter-turn insulation structure, which adopts two separately spliced ​​insulation layers, an inner insulation layer and an outer insulation layer, and provides an insulating covering layer at the connection of the dislocated insulation layers on both sides, so as to reduce the possibility of insulation failure caused by contact of copper chips and dust at the gap.

[0022] 2. The generator has a seamless inter-turn insulation structure, in which the covering layer wraps the arc segment of the rotor coil and extends to the straight segment of the rotor coil. The connection port of the inner insulation layer and the connection port of the outer insulation layer are both located in the straight segment of the rotor coil. This arrangement ensures that the arc segment of the rotor coil can receive enhanced insulation protection.

[0023] 3. The generator has a seamlessly spliced ​​inter-turn insulation structure. The outer surface of the same group of rotor coils is covered with multiple inner insulation layers, and the covering layer covers the outer surface of the connection between two adjacent inner insulation layers. Since the rotor coil is relatively long, the inner insulation layer is arranged inside the entire insulation layer and will be covered by the adhesive and the outer insulation layer after the gap is formed by overlapping. Therefore, the use of multi-segment splicing can reduce the modification cost while having a minimal impact on the insulation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the present invention;

[0025] Figure 2 For the present invention Figure 1 The enlarged schematic diagram at A in the middle;

[0026] Figure 3 It is a schematic diagram of the connection between the inner insulating layer and the covering layer of the present invention;

[0027] Figure 4 This is a schematic diagram of the connection between the covering layer and the protective layer of the present invention;

[0028] Figure 5 This is a schematic diagram of the connection of the covering layer of the present invention.

[0029] In the figure: 1, insulating layer; 101, inner insulating layer; 102, outer insulating layer; 103, covering layer; 104, protective layer. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0031] It should be noted that all directional indications in the embodiments of the present application are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0032] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] In addition, in this application, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0034] like Figure 1-5 As shown, a seamlessly spliced ​​inter-turn insulation structure of a generator includes two layers of insulation layers 1 wrapped around the outside of a rotor coil, the two layers of insulation layers 1 are divided into an inner insulation layer 101 wrapped around the outside of the rotor coil and an outer insulation layer 102 wrapped around the outside of the inner insulation layer 101, the connection ports of the inner insulation layer 101 and the outer insulation layer 102 are staggered, a covering layer 103 is arranged between the inner insulation layer 101 and the outer insulation layer 102, the connection ports of the inner insulation layer 101 and the outer insulation layer 102 both overlap with the covering layer 103, by adopting the insulation layers 1 of the inner insulation layer 101 and the outer insulation layer 102 which are two layers of separately spliced ​​insulation layers 1, and arranging the insulating covering layer 103 at the staggered connection ports of the insulation layers 1 on both sides, the possibility of insulation failure caused by contact of copper chips, dust, etc. at the gap can be reduced.

[0035] The covering layer 103 wraps the arc segment of the rotor coil and extends to the straight segment of the rotor coil. The connection port of the inner insulation layer 101 and the connection port of the outer insulation layer 102 are both located in the straight segment of the rotor coil. This arrangement ensures that the arc segment of the rotor coil can receive enhanced insulation protection.

[0036] The covering layer 103 is made of insulating material, adhesive is coated on both sides of the covering layer 103 , and protective layers 104 for protecting the adhesive are arranged on both sides of the covering layer 103 . Such arrangement can facilitate the use of the covering layer 103 .

[0037] The inner insulating layer 101 and the outer insulating layer 102 have the same width, and the gap distance between the connecting port of the inner insulating layer 101 and the connecting port of the outer insulating layer 102 is at least five times the width of the inner insulating layer 101. This setting can increase the distance between the two overlapping interfaces and avoid insulation failure caused by contact of copper chips and dust accumulated in the gap.

[0038] The thickness of the inner insulating layer 101 and the outer insulating layer 102 are the same, and the thickness of the cover layer 103 is smaller than that of the inner insulating layer 101 . Such an arrangement can reduce the overall thickness of the insulating layer 1 .

[0039] The outer surface of the same group of rotor coils is covered with multiple inner insulating layers 101, and the covering layer 103 covers the outer surface of the connection between two adjacent inner insulating layers 101. Since the rotor coil is relatively long, the inner insulating layer 101 is arranged inside the entire insulating layer 1, and will be covered by the adhesive and the outer insulating layer 102 after overlapping to form a gap. Therefore, the use of multi-section splicing can reduce the modification cost while having a small impact on the insulation effect. At the same time, the covering layer 103 in this part not only covers the insulation, but also connects the adjacent inner insulating layers 101.

[0040] The connection ports of the insulating layer 1 covering the outer surfaces of two adjacent groups of rotor coils are staggered. This arrangement can avoid the accumulation of materials close to each other due to the overlap of the connection ports between the two adjacent groups of rotor coils. The connection ports of the insulating layer 1 covering the outer surfaces of three consecutive rotor coils are arranged in succession in the upper, middle and lower positions. By arranging the upper, middle and lower positions in this way and cycling the arrangement, it is possible to avoid the overlap of adjacent connection ports.

[0041] The bonding process of the insulating layer 1 requires that, first, adhesive is applied to the outer surface of the rotor coil, and secondly, the inner insulating layer 101 is included and bonded to the outer surface of the rotor coil, the inner protective layer 104 of the covering layer 103 is lifted off and covered on the connection port of the inner insulating layer 101, then, the outer protective layer 104 of the covering layer 103 is lifted off, and adhesive is applied to the surfaces of the inner insulating layer 101 and the covering layer 103, and finally, the outer insulating layer 102 is covered on the outer surfaces of the inner insulating layer 101 and the covering layer 103, and it is ensured that the connection port of the outer insulating layer 102 is located at the covering layer 103.

[0042] As a further optimization, multiple inner insulation layers 101 are bonded into a whole inner insulation layer 101 through the covering layer 103, and the single inner insulation layer 101 completely wraps the arc segment of the rotor coil, and the covering layer 103 is located on the straight segment of the rotor coil.

[0043] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0044] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A seamless inter-turn insulation structure for a generator, comprising two insulating layers (1) wrapped around the outer side of a rotor coil, characterized in that: The two insulating layers (1) are divided into an inner insulating layer (101) wrapped around the outside of the rotor coil and an outer insulating layer (102) wrapped around the outside of the inner insulating layer (101); the connection ports of the inner insulating layer (101) and the outer insulating layer (102) are staggered; a covering layer (103) is arranged between the inner insulating layer (101) and the outer insulating layer (102); the connection ports of the inner insulating layer (101) and the outer insulating layer (102) both overlap with the covering layer (103).

2. The generator seamlessly spliced ​​inter-turn insulation structure according to claim 1, characterized in that: The covering layer (103) wraps the arc segment of the rotor coil and extends to the straight segment of the rotor coil, and the connection port of the inner insulating layer (101) and the connection port of the outer insulating layer (102) are both located in the straight segment of the rotor coil.

3. A generator seamlessly spliced ​​inter-turn insulation structure according to claim 1 or 2, characterized in that: The covering layer (103) is made of insulating material, adhesive is coated on both sides of the covering layer (103), and protective layers (104) for protecting the adhesive are arranged on both sides of the covering layer (103).

4. The generator seamlessly spliced ​​inter-turn insulation structure according to claim 3 is characterized in that: The inner insulating layer (101) and the outer insulating layer (102) have the same width, and the gap distance between the connection port of the inner insulating layer (101) and the connection port of the outer insulating layer (102) is at least five times the width of the inner insulating layer (101).

5. The generator seamlessly spliced ​​inter-turn insulation structure according to claim 4, characterized in that: The inner insulating layer (101) and the outer insulating layer (102) have the same thickness, and the covering layer (103) has a thickness smaller than that of the inner insulating layer (101).

6. The generator seamlessly spliced ​​inter-turn insulation structure according to claim 4, characterized in that: The outer surface of the same group of rotor coils is covered with a plurality of inner insulating layers (101), and the covering layer (103) covers the outer surface of the connection port between two adjacent inner insulating layers (101).

7. The generator seamlessly spliced ​​inter-turn insulation structure according to claim 6, characterized in that: The connection openings of the insulating layer (1) covering the outer surfaces of two adjacent groups of rotor coils are staggered, and the connection openings of the insulating layer (1) covering the outer surfaces of three consecutive rotor coils are arranged consecutively in three positions: upper, middle and lower.

8. The generator seamlessly spliced ​​inter-turn insulation structure according to claim 7, characterized in that: The bonding of the insulating layer (1) comprises the following steps: Step 1, applying adhesive to the outer surface of the rotor coil; Step 2: The inner insulating layer (101) is included and bonded to the outer surface of the rotor coil, the inner protective layer (104) of the cover layer (103) is removed, and the inner protective layer (104) is covered on the connection port of the inner insulating layer (101); Step 3, peel off the outer protective layer (104) of the covering layer (103), and apply adhesive on the surface of the inner insulating layer (101) and the covering layer (103); Step 4: Cover the outer surfaces of the inner insulating layer (101) and the covering layer (103) with the outer insulating layer (102), and ensure that the connection port of the outer insulating layer (102) is located at the covering layer (103).

9. The generator seamlessly spliced ​​inter-turn insulation structure according to claim 8, characterized in that: The second step of bonding the insulating layer (1) further comprises: A plurality of inner insulating layers (101) are bonded together into a whole inner insulating layer (101) through a covering layer (103), and a single inner insulating layer (101) completely wraps the circular arc segment of the rotor coil, and the covering layer (103) is located on the straight line segment of the rotor coil.

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