An intelligent mineral insulated cable

Abstract

The present invention discloses an intelligent mineral insulated cable, comprising an inner core structure, a sheath structure, an optical fiber sensor unit, and a communication optical cable unit. The inner core structure includes a central skeleton, within which a plurality of central airbags connected in sequence are mounted. At least three sets of cable cores are disposed externally to the central skeleton, with pressure-resistant components disposed between adjacent cable cores. When the cable is subjected to compressive forces, the central airbags deform, and the gas within the central airbags is discharged into the surrounding air cavity, shrinking the central airbags and freeing up space for the cable cores to prevent damage. Furthermore, due to the support of the elastic member, the cable can quickly recover after the external pressure is removed, thus providing the cable with excellent compression and bending resistance, while ensuring the effective use of the sensors.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of cables, and in particular to an intelligent mineral insulated cable. Background Art

[0002] Mineral insulated cable (MIC) is a cable with a copper sheath surrounding a copper conductor and magnesium oxide powder as an inorganic insulating material to separate the conductor and sheath. An outer protective sheath can be selected as needed. This cable is commonly known as MICC or MI cable. A similar cable, called mineral-insulated metal-sheathed cable, uses metal instead of a copper sheath to surround the core and insulation. Because this cable is made entirely of inorganic materials, it offers advantages not found in other cables.

[0003] However, due to the short operation time of mineral insulated cables in my country and the lack of comprehensive operating experience, the only way to confirm whether cables have safety hazards is based on foreign experience and annual line inspections. The inspection process is cumbersome and time-consuming, and once a failure occurs, it will cause great losses to the national economy. With the development of technology, smart cables have emerged, which embed extremely lightweight and concealed smart chips or sensors, such as fiber optic sensors, into cables to achieve online cable monitoring. However, during use, smart mineral insulated cables are easily damaged by various stresses such as frequent bending and various mechanical extrusions, which can easily damage the cable core. At the same time, it can also easily damage the smart chips or sensors, affecting the cable's performance. Summary of the Invention

[0004] The technical solution of the present invention addresses the technical problem that the existing technical solutions are too single, and provides a solution that is significantly different from the existing technology. It mainly provides an intelligent mineral insulated cable to solve the technical problem raised in the above background technology that the existing intelligent mineral insulated cable has poor compressive performance and cannot protect the cable core and intelligent sensor.

[0005] The technical solution adopted by the present invention to solve the above technical problems is:

[0006] An intelligent mineral insulated cable, comprising an inner core structure, a sheath structure, an optical fiber sensor unit and a communication optical cable unit, wherein the inner core structure comprises a central skeleton, wherein a plurality of central air bags connected in sequence are installed inside the central skeleton, at least three groups of cable cores are provided outside the central skeleton, and a pressure-resistant component is provided between each two adjacent cable cores; the pressure-resistant component comprises a fixed sleeve, wherein an air cavity connected to the central air bag is provided inside the fixed sleeve, a piston plate slides inside the air cavity, an elastic part is connected to the side of the piston plate away from the central air bag and before the side wall of the air cavity, a transmission rod connected to the piston plate is provided next to the elastic part, and the other end of the transmission rod is connected to a pressure-resistant block located outside the fixed sleeve; a protective sleeve is built into the sheath structure, and the protective sleeve comprises a wound mica wrapping tape, and a plurality of slots are provided on the surface of the mica wrapping tape, capsule particles are clamped in some of the slots, and dry powder is filled in the capsule particles.

[0007] Preferably, the central skeleton includes a plurality of equally spaced support rings, the pressure-resistant components are mounted on the support rings, and connecting rods are connected between any two adjacent support rings.

[0008] Preferably, the central airbag is a heat-insulating airbag.

[0009] Preferably, each group of cable cores consists of a twisted conductor, a conductor shielding layer, an insulating layer, an insulating shielding layer and a metal shielding layer from the inside to the outside, the optical fiber sensor unit is implanted in the twisted conductor along the length direction of the twisted conductor, and the communication optical cable unit and the cable core are arranged side by side and installed on a fixed sleeve.

[0010] Preferably, the optical fiber sensor unit is a flexible special optical fiber, and the communication optical cable unit is a multi-core communication optical cable.

[0011] Preferably, the elastic member is a spring.

[0012] Preferably, the sheath structure comprises, from the inside to the outside, a wrapped sheath layer, a quartz mesh layer, a mineral insulation layer, a ceramic polyolefin sheath layer, a nylon sheath layer, a halogen-free low-smoke flame-retardant polyolefin sheath layer, a protective sleeve and an armor layer.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] (1) Under normal conditions, the elastic force of the elastic member prevents the gas inside the central airbag from leaking into the air cavity, ensuring effective support of the central airbag. When external pressure strikes, the cable is squeezed, causing the central airbag to deform. The gas inside the central airbag is discharged into the surrounding air cavity, making the central airbag smaller, freeing up a certain amount of space for the cable core to avoid damage to the cable core. At the same time, due to the support of the elastic member, the cable can quickly recover after the external pressure is removed, so that the cable has good pressure and bending resistance, avoiding damage to the cable during use, and ensuring the effective use of the sensor.

[0015] (2) When the cable encounters a fire, the flame melts the capsule particles, causing the dry powder inside the capsule particles to flow out and cover the cable, while preventing the spread of the flame, improving the overall flame retardancy of the cable, and preventing the flame from directly burning the cable, resulting in a short working time of the cable, unable to meet emergency needs, and increasing the losses caused by the fire;

[0016] (3) The cable core has built-in optical fiber sensor units and communication optical cable units. The optical fiber sensor unit is designed with the Brillouin optical time domain reflectometry technology for sensing system design. Therefore, it can not only detect the temperature of the twisted conductor, but also realize the spatial positioning of the cable and obtain positioning information, thus forming the intelligent cable. The communication optical cable unit is used to transmit system signals. When laying the cable, the communication line is also laid, thus realizing the integration of power and communication.

[0017] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the cross-sectional structure of the present invention;

[0019] Figure 2 Schematic diagram of the cross-sectional structure of the sheath structure of the present invention;

[0020] Figure 3 This is a schematic diagram of the protective cover of the present invention from a top view;

[0021] Figure 4 Schematic diagram of the cross-sectional structure of the inner core structure of the present invention;

[0022] Figure 5 This is a schematic diagram of the central skeleton structure of the present invention;

[0023] Figure 6 Schematic diagram of the cable core structure of the present invention. Description of the drawings:

[0025] 1. Inner core structure; 101. Center airbag;

[0026] 11. Central frame; 111. Support ring; 112. Connecting rod;

[0027] 12. Cable core; 121. Twisted conductor; 122. Conductor shield; 123. Insulation layer; 124. Insulation shield; 125. Metal shield; 126. Optical fiber sensor unit; 127. Communication cable unit;

[0028] 13. Anti-pressure assembly; 131. Fixed sleeve; 132. Air cavity; 133. Piston plate; 134. Elastic member; 135. Transmission rod; 136. Anti-pressure block;

[0029] 2. Sheath structure; 201. Wrapped sheath layer; 202. Quartz mesh layer; 203. Mineral insulation layer; 204. Ceramic polyolefin sheath; 205. Nylon sheath layer; 206. Halogen-free low-smoke flame-retardant polyolefin sheath layer; 207. Armor layer;

[0030] 21. Protective sleeve; 211. Mica wrapping tape; 212. Capsule particles. DETAILED DESCRIPTION

[0031] To facilitate understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in different forms and is not limited to the embodiments described in the text. On the contrary, these embodiments are provided to make the content disclosed in the present invention more thorough and comprehensive.

[0032] It should be noted that when an element is referred to as being "fixed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this article are for illustrative purposes only.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly used by those skilled in the art to which the present invention pertains. The terminology used in the specification of the present invention is for the purpose of describing specific embodiments and is not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0034] Please refer to the attached Figure 1 and 4The present invention provides a technical solution: an intelligent mineral insulated cable, comprising an inner core structure 1, a sheath structure 2, an optical fiber sensor unit 126, and a communication optical cable unit 127. The inner core structure 1 comprises a central skeleton 11, which comprises a plurality of equally spaced support rings 111. The pressure-resistant components 13 are mounted on the support rings 111, and connecting rods 112 are connected between any two adjacent support rings 111. A plurality of central airbags 101 connected in sequence are mounted inside the central skeleton 11. The central airbags 101 are heat-insulating airbags that prevent gas expansion caused by internal cable heat. At least three groups of cable cores 12 are disposed outside the central skeleton 11, and pressure-resistant components 13 are disposed between any two adjacent cable cores 12.

[0035] Please refer to the attached Figure 1 、 4 And 5, the pressure-resistant component 13 includes a fixed sleeve 131, an air cavity 132 connected to the central airbag 101 is provided inside the fixed sleeve 131, a piston plate 133 is slid inside the air cavity 132, and an elastic member 134 is connected to the side of the piston plate 133 away from the central airbag 101 and the side wall of the air cavity 132. The elastic member 134 is a spring, but is not limited to a spring. A transmission rod 135 connected to the piston plate 133 is provided next to the elastic member 134, and the other end of the transmission rod 135 is connected to a pressure-resistant block 136 located outside the fixed sleeve 131. Under normal conditions, due to the elastic support of the elastic member 134, the gas inside the central airbag 101 will not leak into the air cavity 132, ensuring the effective support of the central airbag 101. When external pressure comes, the cable is subjected to extrusion force, causing the central airbag 101 to deform, and the gas inside the central airbag 101 is discharged to the surrounding air cavity 132, making the central airbag 101 smaller, freeing up a certain amount of space for the cable core 12 to avoid damage to the cable core 12. At the same time, due to the support of the elastic member 134, it can quickly recover after the external pressure is withdrawn, so that the cable has good compression and bending resistance.

[0036] Please refer to the attached Figure 1 、 4 and 6, each group of the cable cores 12 comprises, from the inside to the outside, a twisted conductor 121, a conductor shielding layer 122, an insulating layer 123, an insulating shielding layer 124 and a metal shielding layer 125, the optical fiber sensor unit 126 is located inside the cable core 12, and the optical fiber sensor unit 126 is implanted in the twisted conductor 121 along the length direction of the twisted conductor 121, the communication optical cable unit 127 is located outside the cable core 12 and inside the inner core structure 1, and the communication optical cable unit 127 and the cable core 12 are arranged side by side.

[0037] The optical fiber sensor unit 126 is a flexible special optical fiber, which includes a flexible special single-mode optical fiber or a flexible special multi-mode optical fiber. The use of flexible optical fiber makes it easy to implant the optical fiber sensor unit 126 into the twisted conductor 121. The optical fiber sensor unit 126 arranged along the twisted conductor 121 can monitor the temperature of the entire cable twisted conductor 121 in a distributed online manner. The twisted conductor 121 is the main structure for realizing the electrical conductivity of the cable and is also the main heat-generating part of the cable during the electrical conduction process. The temperature of the twisted conductor 121 determines the temperature of the entire cable. Therefore, implanting the optical fiber sensor unit 126 into the twisted conductor 121 can most directly detect the temperature of the cable. The optical fiber sensor unit 126 adopts Brillouin optical time domain reflectometry (BOTDR) technology for sensing system design. The BOTDR distributed optical fiber sensor uses Brillouin scattered light detection technology and advanced OTDR technology for spatial positioning. Therefore, it can not only detect the temperature of the twisted conductor 121, but also realize spatial positioning of the cable and obtain positioning information to form an intelligent cable. The twisted conductor 121 can be made of copper wires or aluminum wires, and the optical fiber sensor unit 126 is arranged at any position between the twisted copper wires or aluminum wires. There is no specific limitation on its position, as long as the optical fiber sensor unit 126 is set anywhere in the length direction of the twisted conductor 121.

[0038] The communication optical cable unit 127 can adopt a multi-core communication optical cable for transmitting system signals. The communication optical cable unit 127 and the cable core 12 are arranged side by side and installed on the fixing sleeve 131. This setting method utilizes the layout of the communication optical cable unit 127 to achieve protection of the communication optical cable unit 127. By setting up the communication optical cable unit 127, the communication line is also set up while the cable is set up, realizing the integration of power and communication.

[0039] Please refer to the attached Figure 1-3 The sheath structure 2 includes a protective sleeve 21, which comprises a wound mica wrapping tape 211. The mica wrapping tape 211 has a plurality of slots formed on its surface. Some of these slots contain capsule particles 212, which are filled with dry powder. In the event of a fire, the flames melt the capsule particles 212, causing the dry powder inside to flow out. The dry powder covers the cable, preventing the spread of flames and improving the overall flame retardancy of the cable. This prevents the flames from directly burning the cable, which would otherwise shorten its service life, fail to meet emergency needs, and increase fire losses.

[0040] Please refer to the attached Figure 1-3The sheath structure 2 comprises, from the inside out, a wrapped sheath layer 201, a quartz mesh layer 202, a mineral insulation layer 203, a ceramic polyolefin sheath 204, a nylon sheath layer 205, a halogen-free, low-smoke, flame-retardant polyolefin sheath layer 206, a protective sleeve 21, and an armor layer 207. The sheath structure 2 is a multi-layered structure that, while ensuring effective cable insulation, possesses numerous excellent physical and chemical properties, including high mechanical strength, high hardness, wear and tear resistance, superior electrical insulation, and resistance to acids (including formic acid), alkalis, and most inorganic salt solutions. It is also termite-proof, rat-proof, wear-resistant, corrosion-resistant, durable, and non-toxic and environmentally friendly.

[0041] The above description of the present invention is exemplified in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as such non-substantial improvements are made using the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the scope of protection of the present invention.

Claims

1. An intelligent mineral insulated cable, comprising an inner core structure (1), a sheath structure (2), an optical fiber sensor unit (126) and a communication optical cable unit (127), characterized in that: The inner core structure (1) comprises a central skeleton (11), a plurality of central air bags (101) connected in sequence are installed inside the central skeleton (11), at least three groups of cable cores (12) are arranged outside the central skeleton (11), and pressure-resistant components (13) are arranged between two adjacent cable cores (12); The anti-pressure component (13) includes a fixed sleeve (131), an air cavity (132) connected to the central air bag (101) is provided inside the fixed sleeve (131), a piston plate (133) slides inside the air cavity (132), an elastic member (134) is connected to the side of the piston plate (133) away from the central air bag (101) and between the side wall of the air cavity (132), a transmission rod (135) connected to the piston plate (133) is provided next to the elastic member (134), and the other end of the transmission rod (135) is connected to an anti-pressure block (136) located outside the fixed sleeve (131); The sheath structure (2) has a built-in protective sleeve (21), the protective sleeve (21) comprising a wound mica wrapping tape (211), a surface of the mica wrapping tape (211) being provided with a plurality of slots, some of the slots being internally engaged with capsule particles (212), and the capsule particles (212) being internally filled with dry powder; The central skeleton (11) comprises a plurality of equally spaced support rings (111), the compression-resistant components (13) are mounted on the support rings (111), and connecting rods (112) are connected between two adjacent support rings (111); The central airbag (101) is a heat-insulating airbag.

2. The intelligent mineral insulated cable according to claim 1, characterized in that: Each group of cable cores (12) comprises, from the inside to the outside, a twisted conductor (121), a conductor shielding layer (122), an insulating layer (123), an insulating shielding layer (124), and a metal shielding layer (125); the optical fiber sensor unit (126) is implanted in the twisted conductor (121) along the length direction of the twisted conductor (121); the communication optical cable unit (127) and the cable core (12) are arranged side by side and mounted on a fixing sleeve (131).

3. The intelligent mineral insulated cable according to claim 2, characterized in that: The optical fiber sensor unit (126) is a flexible special optical fiber, and the communication optical cable unit (127) is a multi-core communication optical cable.

4. The intelligent mineral insulated cable according to claim 1, characterized in that: The elastic member (134) is a spring.

5. The intelligent mineral insulated cable according to claim 1, characterized in that: The sheath structure (2) comprises, from the inside to the outside, a wrapped sheath layer (201), a quartz mesh layer (202), a mineral insulation layer (203), a ceramicized polyolefin sheath (204), a nylon sheath layer (205), a halogen-free low-smoke flame-retardant polyolefin sheath layer (206), a protective sleeve (21), and an armor layer (207).

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