A high-current flexible flat cable

Abstract

This utility model discloses a high-current flexible flat cable, aiming to solve the problem of excessive losses in existing cables under high-current, low-voltage conditions. The utility model includes several stacked flat conductors and a wrapping tape layer, an insulation layer, and an outer sheath disposed outside the flat conductors. In the cross-section of the flexible flat cable, the flat conductors are wavy with crests and troughs, and the crests and troughs of adjacent flat conductors interlock without gaps. The use of stacked flat conductors reduces the skin effect and proximity effect on the conductor surface, thereby reducing line losses.

Description

Technical Field

[0001] This utility model relates to the field of conductive wire harnesses, and more specifically, it relates to a high-current flexible flat cable. Background Technology

[0002] In global power engineering construction, the demand for long-distance, high-current low-voltage cables for applications such as photovoltaics, energy storage, and new energy charging piles is increasing. The global market for high-current low-voltage cables is showing a continuous growth trend; according to incomplete statistics, the market for low-voltage high-current transmission and distribution conductors and cables will exceed 300 billion yuan. With the accelerated promotion of national "carbon neutrality" and "carbon peaking" initiatives, and the construction of urban power transmission and distribution grids, the main applications of high-current low-voltage cables include: power transmission and distribution systems, high and low voltage electrical appliances, construction, transportation, communications, energy, and new energy vehicles and smart grids.

[0003] For example, in Chinese patent literature, patent number CN 202010337625.2 disclosed on September 18, 2020, a flexible flat cable resistant to nuclear electromagnetic high current. This application includes several insulated cores and a sheath disposed outside the insulated cores. The insulated cores include conductors arranged from the inside out, an insulation layer extruded outside the conductors, and a shielding layer. The conductors are several horizontally arranged adjacent sub-conductors.

[0004] The shortcoming of the existing technology is that the cable with this property has a very obvious skin effect. Simply increasing the thickness of the conductor in the cable has low marginal benefits. Because multiple parallel cables with the same current direction are arranged, a significant proximity effect will be generated, resulting in greater cable loss, which cannot meet the current demand for high current and low voltage cables. Utility Model Content

[0005] This invention overcomes the shortcomings of existing cables that suffer huge losses in high-current, low-voltage scenarios, and provides a high-current flexible flat cable that can reduce transmission losses and meet the needs of high-current, low-voltage scenarios.

[0006] In addition, most existing cables have a circular cross-section, which takes up a lot of space. This application also provides a high-current flexible flat cable that takes up less space and is easy to deploy in cable tray space.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] A high-current flexible flat cable includes several stacked flat conductors and a wrapping tape layer, an insulation layer, and an outer sheath disposed outside the flat conductors. In the cross-section of the flexible flat cable, the flat conductors are wavy and have crests and troughs. The crests and troughs of adjacent flat conductors are interlocked without gaps.

[0009] The cable transmits charge through several overlapping flat conductors. The wavy structure of the flat conductors and the interlocking of adjacent flat conductors without gaps increase the contact area, reduce contact resistance, and reduce the skin effect and proximity effect on the conductor surface. According to actual tests, the energy loss during transmission is only 1% of the transmitted power, while the loss of conventional wires and cables can reach 10%. Compared with traditional low-voltage multi-segment cables, a single flexible flat cable can carry a current of up to 3000A, which is 6 to 10 times higher than that of conventional cables.

[0010] The flexibility of cables lies in the fact that the number of flat conductors can be easily increased or decreased according to needs, thus allowing for arbitrary expansion over a large range.

[0011] Even more remarkably, the shape of flat cables is suitable for laying in bridges, requiring only 40-60% of the original ground space, greatly reducing construction costs for enterprises and users.

[0012] Preferably, the width of the crests and troughs is 0.5 mm and the height is 0.5 mm.

[0013] Preferably, the flat conductor is sinusoidal in shape. Flat conductors have fewer stress concentration points and therefore higher reliability.

[0014] Preferably, the flat conductor is triangularly wavy.

[0015] Preferably, the wrapping layer consists of several alkali-free glass cloth wrapping layers wrapped around the outside of the flat conductor. The alkali-free glass cloth wrapping layers overlap, and the thickness of the alkali-free glass cloth wrapping layers is 0.15 to 0.20 mm. The wrapping overlap width is greater than or equal to 5 mm, thereby improving fire resistance.

[0016] Preferably, the insulation layer is made of cross-linked polyethylene or halogen-free polyolefin, and the thickness of the insulation layer is 1.0-3.0 mm. The insulation layer is formed by extrusion.

[0017] Preferably, the outer sheath is made of low-smoke halogen-free polyolefin. Through extrusion insulation, it exhibits high electrical insulation performance and resistance to both low and high temperatures.

[0018] Preferably, the system also includes a detection harness, which is disposed within the insulation layer and located on one or both sides of the flat conductor along its width. The detection harness, from the outside in, includes a detection sheath, several fiber optic bundles, and a glass fiber bundle. The fiber optic bundles include multimode fibers for connecting to the DTS (Distributed Transmission System) and single-mode fibers for connecting to the DAS (Distributed Amplifier System) and strain monitoring system. The fiber optic bundles are twisted around the glass fiber bundles with a twist ratio of 60-80. By using the detection harness, comprehensive visual monitoring of the line and rapid fault location are achieved, providing a favorable guarantee for safe power monitoring and management.

[0019] Preferably, the fiber bundle is filled with aramid and tightly wrapped with TPEE.

[0020] As a preferred option, the material of the testing sleeve is HDPE.

[0021] Compared with the prior art, the beneficial effects of this utility model are:

[0022] (1) Using flat conductors stacked together reduces the skin effect and proximity effect on the conductor surface, thus reducing line loss;

[0023] (2) Stacking the appropriate number of flat conductors as needed makes it easy to expand the model, which reflects the flexibility of the wire harness in this application;

[0024] (3) The detection harnesses set up provide comprehensive visual monitoring and rapid fault location of the line, which provides a favorable guarantee for safe power monitoring and management. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the flat conductor of this utility model;

[0026] Figure 2 This is a schematic diagram of several flat conductors overlapping in this utility model;

[0027] Figure 3 This is a cross-sectional view of the cable of this utility model;

[0028] In the picture:

[0029] 1. Flat conductor, 2. Wrapping tape layer, 3. Insulation layer, 4. Outer sheath, 5. Crest, 6. Trough, 7. Detection wire bundle, 8. Detection sheath, 9. Fiber optic bundle, 10. Glass fiber bundle. Detailed Implementation

[0030] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0031] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0032] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0033] In the present disclosure, terms such as "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "side", "bottom", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These are only relational terms determined for the convenience of describing the structural relationships of various components or elements of the present disclosure, and do not specifically refer to any component or element in the present disclosure, and should not be construed as a limitation to the present disclosure.

[0034] In the present disclosure, terms such as "fixed connection", "connected", "joined" should be understood in a broad sense, which may mean a fixed connection, an integral connection or a detachable connection; it may be directly connected or indirectly connected through an intermediate medium. For those skilled in relevant scientific research or technology in this field, the specific meanings of the above terms in the present disclosure can be determined according to specific circumstances, and should not be construed as a limitation to the present disclosure.

[0035] Embodiment:

[0036] A large-current flexible flat cable, as shown in the figure, includes several stacked flat conductors 1 and a wrapping tape layer 2, an insulating layer 3 and an outer sheath 4 provided outside the flat conductor 1. In the cross-section of the flexible flat cable, the flat conductor 1 is in a wavy shape and has wave peaks 5 and wave valleys 6. The wave peaks 5 and wave valleys 6 of adjacent flat conductors 1 are respectively engaged without gaps. Figures 1 to 3 As shown in the figure, specifically, the top surface of the flat conductor 1 is provided with a wave peak 5, and corresponding to the wave peak 5, the bottom surface of the flat conductor 1 is provided with a wave valley 6. The wave peaks 5 and wave valleys 6 have the same height. Adjacent to the wave peak 5 on the top surface is provided with a wave valley 6, and corresponding to this wave valley 6, the bottom surface is provided with a wave peak 5 at the corresponding position.

[0037] As shown in the figure Figure 2 Specifically, the top surface of the flat conductor 1 is provided with a wave peak 5, and corresponding to the wave peak 5, the bottom surface of the flat conductor 1 is provided with a wave valley 6. The wave peaks 5 and wave valleys 6 have the same height. Adjacent to the wave peak 5 on the top surface is provided with a wave valley 6, and corresponding to this wave valley 6, the bottom surface is provided with a wave peak 5 at the corresponding position.

[0038] The flat conductor 1 is arranged in a wavy shape for two purposes: First, it can increase the contact area with the adjacent flat conductor 1; Second, it can be better coordinated with the adjacent flat conductor 1, so as to perform pre-positioning before the wrapping tape is wrapped.

[0039] As shown in the figure Figure 1 In some embodiments, for each flat conductor 1, the distance between any two adjacent wave peaks 5 or wave valleys 6 is the same, which can help the flat conductor 1 to be better engaged and eliminate gaps. Among them, the flat conductor 1 is in a sine wave shape in some embodiments. There are few stress concentration points on the flat conductor 1, and the reliability of the flat conductor 1 is relatively high. In other embodiments, the flat conductor 1 is in a triangular wave shape, and the peak parts of the wave peaks 5 and wave valleys 6 are rounded or chamfered. Specifically, the widths of the wave peaks 5 and wave valleys 6 are 0.5 mm, and the heights are 0.5 mm. The slope of the midpoint between the wave peaks 5 and wave valleys 6 is approximately 1. [[ID=​In some embodiments, the flat conductor 1 is a foil. In other embodiments, the flat conductor 1 is a copper rod with a copper content of 99.95%, which is extruded into a flat copper bar by an extruder, and then multiple grooves are milled on the upper and lower planes of the copper bar using a high-speed multi-head hob.

[0041] The wrapping tape layer 2 is composed of several non-alkali fiberglass tape wrapped around the outside of the flat conductor 1. The non-alkali fiberglass tape is overlapped and wrapped. The thickness of the non-alkali fiberglass tape is 0.15 to 0.20 mm, and the wrapping overlap width is greater than or equal to 5 mm to improve the fire resistance performance. The material of the insulating layer 3 is cross-linked polyethylene insulation or halogen-free polyolefin. The thickness of the insulating layer 3 is 1.0 - 3.0 mm. The insulating layer 3 is formed by extrusion coating. The material of the outer sheath 4 is low-smoke and halogen-free polyolefin. By extruding insulation, it has high electrical insulation performance, resistance to low temperature and high temperature.

[0042] The cable transmits electric charge through the several overlapping flat conductors 1. The flat conductor 1 has a wavy structure and adjacent flat conductors 1 are meshed without gaps, which increases the contact area, reduces the contact resistance, reduces the skin effect and proximity effect on the conductor surface. According to actual tests, the power loss during the transmission of electric energy is only 1% of the transmission power, while the loss of conventional wire and cable reaches 10%. Compared with traditional low-voltage multi-strand cables, the current-carrying capacity of a single flexible flat cable can reach 3000 A, which is 6 - 10 times higher than that of conventional cables.

[0043] The flexibility of the cable is reflected in that the number of flat conductors 1 can be simply increased or decreased according to requirements, so as to be arbitrarily expanded within a large range.

[0044] More remarkably, the shape of the flat cable is suitable for laying in a bridge, and the required floor area and space are only 40 - 60% of the original, which greatly reduces the construction cost for enterprises and users.

[0045] See Figure 3 As shown, it further includes a detection wire harness 7. The detection wire harness 7 is arranged in the insulating layer 3 and on one side or both sides in the width direction of the flat conductor 1. The detection wire harness 7 includes a detection sheath 8, several fiber optic bundles 9 and fiberglass bundles 10 from the outside to the inside. Among them, the fiber optic bundle 9 includes multi-mode fibers for connecting DTS and single-mode fibers for connecting DAS (passive indoor distribution system) and strain monitoring system. The fiber optic bundle 9 is stranded around the fiberglass bundle 10, and the stranding pitch diameter ratio is 60 - 80 times. The fiber optic bundle 9 is filled with aramid and tightly wrapped with TPEE (polyester rubber). The material of the detection sheath 8 is HDPE (high-density polyethylene), which is also produced by extrusion coating. The optical fiber comb includes two multi-mode fibers for connecting DTS (distributed optical cable line warning system), two single-mode fibers for connecting DTS and two single-mode fibers for connecting the strain monitoring system. However, it is not limited to this, and the corresponding optical fibers of other detection systems can also be set.

[0046] By setting up detection harness 7, the line can be monitored in a comprehensive and visual manner, and faults can be located quickly, providing a favorable guarantee for safe electricity monitoring and management.

[0047] The embodiments described above are merely preferred solutions of this utility model and are not intended to limit this utility model in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. A high current flexible flat cable, characterized by, It includes several overlapping flat conductors and a wrapping tape layer, an insulation layer and an outer sheath disposed outside the flat conductors. On the cross-section of the flexible flat cable, the flat conductors are wavy and have crests and troughs. The crests and troughs of adjacent flat conductors are interlocked and without gaps.

2. A high current flexible flat cable according to claim 1, characterized in that, The width of the crests and troughs is 0.5 mm, and the height is 0.5 mm.

3. A large current flexible flat cable according to claim 1, characterized in that, The flat conductor has a triangular wave shape.

4. A high current flexible flat cable according to claim 1, characterized in that, The flat conductor exhibits a sinusoidal wave shape.

5. A high current flexible flat cable according to claim 1, characterized in that, The wrapping layer consists of several alkali-free glass cloth wrapping layers wrapped around the outside of the flat conductor. The alkali-free glass cloth wrapping layers overlap and wrap, with a thickness of 0.15 to 0.20 mm and an overlap width of 5 mm or more.

6. A high current flexible flat cable according to claim 1, characterized in that, The insulation layer is made of cross-linked polyethylene or halogen-free polyolefin, and its thickness is 1.0-3.0 mm.

7. A high current flexible flat cable according to claim 1, characterized in that, The outer sheath is made of low-smoke halogen-free polyolefin.

8. A high-current flexible flat cable according to any one of claims 1 to 7, characterized in that It also includes a detection bundle, which is disposed in the insulation layer and located on one or both sides of the width direction of the flat conductor. The detection bundle includes a detection sheath, several fiber bundles and glass fiber bundles from the outside to the inside. The fiber bundles include multimode fiber for connecting the DTS and single-mode fiber for connecting the DAS and strain monitoring system. The fiber bundles are twisted around the glass fiber bundles with a twist pitch ratio of 60-80.

9. A high current flexible flat cable according to claim 8, characterized in that, The fiber bundle is filled with aramid fiber and tightly wrapped with TPEE.

10. A high current flexible flat cable according to claim 8, characterized in that, The material of the testing sleeve is HDPE.

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