CN217468064U - Power cable for electrified railway - Google Patents

Abstract

The utility model discloses a power cable for electrified railway, including optic fibre temperature sensor, the inseparable conductor of abnormal shape, insulating layer, copper shielding layer, isolation layer, first armor, optic fibre temperature vibration sensor and oversheath, optic fibre temperature sensor, the inseparable conductor of abnormal shape, conductor shielding layer, polypropylene insulating layer, insulation shielding layer, semi-conductive area from interior to exterior set gradually around covering, copper shielding layer, isolation layer, first armor and oversheath, optic fibre temperature vibration sensor sets up in first armor. The cable temperature monitoring device has the functions of monitoring conductor temperature, monitoring cable vibration and monitoring cable outer layer temperature, contrasts and analyzes temperature through the conductor built-in optical fiber temperature sensor and the armor layer optical fiber sensor, contrasts and analyzes temperature rise time and temperature rise rate, and determines the heating position of the cable.

Description

Power cable for electrified railway

Technical Field

The utility model belongs to the technical field of the cable, concretely relates to power cable for electric railway.

Background

In recent years, the high-speed railway in China is rapidly developed, and after four transverse four-longitudinal high-speed railway lines are completed in 2008, the middle and long-term railway network planning is started in 2015. The planning indicates that the period is 2016 to 2025, and the period is expected to be 2030, so that the construction of the eight-horizontal eight-vertical railway network is completed. High speed railways need to traverse complex environments such as: tunnels, plateaus, etc. With the construction of railway networks in future, the safety and reliability of power supply systems are particularly important under complex working conditions of large-length tunnels, plateaus and the like. Simultaneously along with the continuous speeding up of high-speed railway, the demand of high-speed railway to the electric energy constantly strengthens, if only satisfy the electric energy demand through the conductor cross-section that increases crosslinked polyethylene insulated power cable, this can increase the construction cost of railway, causes unnecessary cost and energy consumption extravagant simultaneously. In order to improve the safety and reliability of the 27.5kV power cable of the electrified railway and realize early warning of abnormal line temperature, vibration and the like, a polypropylene insulated intelligent power cable capable of monitoring the cable temperature, the line vibration and the early warning of the abnormality in real time is needed.

The patent of publication No. CN 111430064A relates to a single-phase alternating current intelligent monitoring cable for railways and a production process thereof, and discloses a single-phase alternating current intelligent monitoring cable for railways, which comprises a conductor, a conductor shielding layer, an insulating shielding layer, an inner sheath, a low-smoke halogen-free flame-retardant wrapping tape, a metal wire armor layer, a flame-retardant glass fiber tape and a sheath, which are sequentially arranged from inside to outside; the inner sheath is of a double-layer structure and comprises an elastic semi-conducting layer and a medium-density polyethylene layer which are sequentially arranged outside the insulating shielding layer, and a metal shielding layer embedded between the semi-conducting layer and the medium-density polyethylene; the detection optical fiber comprises a first detection optical fiber arranged in the center of the conductor. The detection optical fibers are arranged in the center of the conductor, so that the temperature of the conductor is detected, the service life of the cable is evaluated, and the accurate detection of the temperature is realized.

It has the following disadvantages:

the cable insulation is crosslinked polyethylene, the maximum operating temperature is 90 ℃, and the current carrying capacity of the cable cannot be exerted by temperature measurement in the state. The cable only describes the measurement of conductor temperature, but the test does not reflect whether the temperature is increased due to an increase in current carrying capacity or whether the cable insulation degrades causing heating. Meanwhile, the optical fiber is placed on the metal shielding layer, but the structure of the optical fiber is not clear, and the position is small in coil in production, so that the continuous production of the cable is not facilitated, and the connection phenomenon can be generated. Meanwhile, the position is close to the main heating position of the cable, namely the central conductor, so that the internal and external states of the cable cannot be reflected in time, and the fact that the external temperature is high or the internal temperature is high is uncertain.

The temperature measuring optical cable and the copper wire conductor are twisted together by adopting a round monofilament pressing structure to form a twisted conductor, and the temperature measuring optical cable is wrapped by the copper wire conductor; this kind of circular conductor structure that sticiss has destroyed original stable structure that sticiss the structure owing to replaced original center copper line with the temperature measurement optical cable, and structural deformation can take place in the production process of conductor and lead to the temperature measurement optical cable pressurized to lead to the optic fibre decay curve to appear the ladder, and this accuracy that influences the optic fibre temperature measurement. Especially in the connection process of the cable line and the accessory, the wiring terminal needs to be pressed on the conductor by adopting hydraulic pliers, the hydraulic mould is of a hexagonal structure, the pressing pressure of the hydraulic pliers is at least 10 tons, the stability of the hollow circular conductor can be seriously damaged by the superposition of the two adverse conditions, the temperature measuring optical cable is damaged, the temperature measuring optical cable cannot be normally used due to the serious condition, the cable line needs to be replaced or the cable joint needs to be added for maintenance, the cable joint is the position with the highest fault occurrence rate of the cable line, and the potential safety hazard of the cable line is increased.

The patent with publication number CN 111477398A relates to an intelligent sensing photoelectric composite cable, and discloses an intelligent sensing photoelectric composite cable, wherein a conductor shielding layer, an insulating layer and an insulating shielding layer are arranged outside a cable core, and at least one communication optical fiber is arranged between metal wires of the metal wire shielding layer in a shielding structure in an inserting manner; the shielding structure is provided with an isolation sleeve, the periphery of the isolation sleeve is provided with a steel wire armor layer, and at least one temperature measuring optical fiber is inserted between steel wires of the steel wire armor layer; the temperature measuring optical fiber comprises a temperature measuring fiber core, a temperature measuring cladding and a heat conducting layer, and heat conducting filling paste is filled between the heat conducting layer and the metal outer tube. The cable can realize real-time intelligent monitoring of the operation condition of the power load of the cable, ensures the synchronization of power supply, communication and on-line monitoring, and has the advantages of reasonable structure and reliable use.

It has the following disadvantages:

according to the scheme, the communication optical cable is placed on the metal shielding layer in the conventional cable structure, and the temperature measuring optical fiber is placed in the steel wire armor layer, so that the cost and the production difficulty of the cable are increased. The temperature measuring optical cable is arranged on the armor layer, the distance between the temperature measuring position and the cable conductor is far, and the temperature measuring optical cable is greatly influenced by the outside. The main technical parameters of the cable are conductor operating temperature, and the model parameters are complex and the accuracy is not high in the subsequent data processing.

Disclosure of Invention

The utility model provides a power cable for electrified railway through the built-in optic fibre temperature sensor real-time supervision conductor temperature of conductor, through the built-in optic fibre temperature vibration sensor monitoring line vibration of armor and sheath temperature, improves power cable's reliability.

In order to achieve the above object, a power cable for electric railway, including optic fibre temperature sensor, heterotypic inseparable conductor, insulating layer, copper shield layer, isolation layer, first armor, optic fibre temperature vibration sensor and oversheath, optic fibre temperature sensor, heterotypic inseparable conductor, conductor shielding layer, polypropylene insulation layer, insulation shielding layer, semi-conductive tape set gradually from inside to outside around covering, copper shield layer, isolation layer, first armor and oversheath, optic fibre temperature vibration sensor sets up in first armor.

Furthermore, the optical fiber temperature sensor is twisted with the special-shaped compact conductor.

Furthermore, the special-shaped compact conductor comprises a plurality of layers of annular structures which are sequentially arranged from inside to outside, and each layer of annular structure is formed by stranding copper single wires.

Furthermore, the insulating layer comprises a conductor shielding layer, a polypropylene insulating layer and an insulating shielding layer which are sequentially arranged from inside to outside.

Furthermore, a semi-conductive tape wrapping layer is wrapped outside the insulating shielding layer.

Further, optical fiber temperature sensor includes first temperature sensing unit, first aramid fiber reinforcement, first protective tube, second armor, first aramid fiber enhancement layer and first woven metal layer, and first protective tube, second armor, first aramid fiber enhancement layer and first woven metal layer set gradually from inside to outside, and first temperature sensing unit all sets up in first protective tube with first aramid fiber reinforcement.

Furthermore, the first protection pipe is made of PTFE material.

Further, the first temperature sensing unit comprises two 62.5/125 μm multimode special optical fibers.

Furthermore, optic fibre temperature vibration sensor is including vibration sensing unit, second temperature sensing unit, second aramid fiber reinforcement, second protection tube, third armor, second aramid fiber enhancement layer and second metal weaving layer, and second protection tube, third armor, second aramid fiber enhancement layer and second metal weaving layer set gradually from inside to outside, and vibration sensing unit, second temperature sensing unit and second aramid fiber reinforcement set up in the second protection tube.

Compared with the prior art, the utility model discloses following profitable technological effect has at least:

the utility model provides a power cable for electrified railway puts at cable central point and sets up optic fibre temperature sensor, sets up optic fibre temperature vibration sensor at the first armor that is close to the cable outside, has conductor temperature monitoring, cable vibration monitoring, the outer temperature monitoring function of cable, through built-in optic fibre temperature sensor of conductor and armor optic fibre sensor, carries out contrastive analysis to the temperature, contrastive analysis intensification time and rate of rise, confirms the cable position that generates heat.

Further, cable cooperation back level system of observing and controling can realize that the damaged cable that leads to of oversheath advances fault monitoring functions such as monitoring, shielding layer and armor ground connection, and the theory of operation that the monitoring was advanced to the cable is: when the outer sheath is damaged, water permeates into the cable, the water can permeate into the first armor layer distributed with the optical fiber temperature vibration sensor after the cable enters water, the temperature of the optical fiber in the optical fiber temperature vibration sensor at the water inlet position is reduced when water enters, and the temperature is gradually reduced from the water inlet point to the two sides; the fault monitoring principle is as follows: the temperature of the point can be increased due to the fault, the temperature high point can be identified by the first armor layer temperature measuring optical fiber, and the ground fault caused by external impact can be identified by the vibration optical fiber in a combined mode. The temperature of a cable line can be sensed, abnormal temperature and occurrence position can be found, the current-carrying capacity of the cable can be effectively improved, and the utilization rate and the use value of the cable can be improved. Meanwhile, the double monitoring of temperature and vibration can effectively prevent the occurrence of cable faults, so that the cable faults can be sensed and positioned in advance, the reliability of a cable line is improved, and the safe operation of a power system is ensured.

Furthermore, the single mode fiber for vibration in the fiber temperature vibration sensor can realize the transmission of monitoring data, and the function can also realize the data transmission function through additionally adding the fiber for special purpose.

Further, the conductor center is that optic fibre temperature sensor place space is the cavity circular, and the stability of circle in the multiplicable conductor cavity of the inseparable conductor of type provides stable circular spatial structure for optic fibre temperature sensor, avoids optic fibre impaired when cable accessories connects, avoids optic fibre temperature sensor to receive the conductor extrusion, ensures conductor structure's stability, guarantees optic fibre sensing's the degree of accuracy.

Furthermore, the special-shaped compact conductor comprises a plurality of layers of annular structures which are sequentially arranged from inside to outside, each layer of annular structure is obtained by stranding copper single wires, a supporting effect is achieved between the annular structures, and the structure is more stable.

Furthermore, the insulating material is polypropylene, compared with a crosslinked polyethylene insulating material, the conductor operating temperature of the cable can be increased from 90 ℃ to 105 ℃, and the current-carrying capacity of the cable is increased. Compared with crosslinked polyethylene, the polypropylene material has a water tree resistance function, and can improve the safety and reliability of the cable under complex working conditions such as tunnels and plateaus.

Furthermore, the insulating shielding layer is formed by wrapping a layer of semi-conducting belt, so that the copper wire shielded by the copper wire and the copper belt can be prevented from damaging the insulating shielding layer under the high-temperature condition in the production and running processes of the cable, and the safety of a cable line is improved.

Furthermore, the reinforced structure of the optical fiber sensor adopts a flexible armored steel pipe, an aramid fiber reinforced layer and a metal woven structure, so that the optical fiber sensor structure and the internal optical fiber can be effectively protected.

The first protection pipe and the second protection pipe are made of PTFE materials, the long-term service temperature of the materials can reach 200-260 ℃, the materials are still soft at minus 100 ℃, the best aging life and the minimum friction coefficient of plastics are also possessed, and optical fibers of the optical fiber sensor can be effectively protected.

Drawings

FIG. 1 is a schematic structural view of a power cable for an electrified railway according to the present invention;

FIG. 2 is a schematic structural view of a power cable optical fiber temperature sensor for an electrified railway according to the present invention;

FIG. 3 is a schematic structural view of a power cable optical fiber temperature vibration sensor for an electrified railway according to the present invention;

fig. 4 is a schematic view of a monitoring system for a power cable for an electric railway according to the present invention.

In the drawings: 1. optical fiber temperature sensor, 2, the inseparable conductor of abnormal shape, 3, the conductor shielding layer, 4, the polypropylene insulating layer, 5, the insulation shielding layer, 6, the semiconductive belt is around the covering, 7, the copper shield layer, 8, the isolation layer, 9, first armor, 10, optical fiber temperature vibration sensor, 11, the oversheath, 21, first temperature sensing unit, 22, first aramid fiber reinforcement, 23, first protective tube, 24, the second armor, 25, first aramid fiber reinforced layer, 26, first metal braid layer, 31, vibration sensing unit, 32, second temperature sensing unit, 33, second aramid fiber reinforcement, 34, the second protective tube, 35, the third armor, 36, second aramid fiber reinforced layer, 37 second braid.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

In order to make the technical solutions in the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, but not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall fall within the protection scope of the present invention.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present. As used herein, the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the invention and to simplify the description, but are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the invention.

Unless defined otherwise, 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 invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Example 1

Referring to fig. 1, the power cable for the electrified railway is a 27.5kV single-core power cable for the electrified railway, and comprises an optical fiber temperature sensor 1, a special-shaped compact conductor 2, a conductor shielding layer 3, a polypropylene insulating layer 4, an insulating shielding layer 5, a semi-conducting tape wrapping layer 6, a copper shielding layer 7, an isolation layer 8, a first armor layer 9, an optical fiber temperature vibration sensor 10 and an outer sheath 11. Optical fiber temperature sensor 1, heterotypic inseparable conductor 2, conductor shielding layer 3, polypropylene insulating layer 4, insulation shielding layer 5, semi-conductive area set gradually from inside to outside around covering 6, copper shield 7, isolation layer 8, first armor 9 and oversheath 11, and first armor 9 is the aluminium silk armor, and optical fiber temperature vibration sensor 10 sets up in first armor 9.

Referring to fig. 2, the optical fiber temperature sensor 1 is composed of a first temperature sensing unit 21, a first aramid fiber reinforcement 22, a first protection tube 23, a second armor layer 24, a first aramid fiber reinforcement layer 25 and a first metal braid layer 26, the first protection tube 23, the second armor layer 24, the first aramid fiber reinforcement layer 25 and the first metal braid layer 26 are sequentially arranged from inside to outside, and the two first temperature sensing units 21 and the first aramid fiber reinforcement 22 are both arranged in the first protection tube 23. The second armor layer 24 is a spiral steel pipe armor layer, and the optical fiber temperature sensor structure can be adjusted according to use scenes and specific requirements.

The first temperature sensing unit 21 consists of two 62.5/125 mu m multimode special optical fibers, the model G651 multimode special optical fiber can be selected, the long-term working temperature of the optical fiber is 150 ℃, the short-term working temperature of the optical fiber is 250 ℃, the influence of the temperature of the cable on the attenuation performance of the optical fiber in the cross-linking production and use processes can be met, and the temperature measurement accuracy is ensured. Meanwhile, the first protection pipe 23 and the second protection pipe 34 are made of PTFE materials, the long-term service temperature of the materials can reach 200-260 ℃, and the melting temperature is 327-342 ℃. The fiber is still soft at the temperature of-100 ℃, has the best aging life and the minimum friction coefficient in plastic, and can effectively protect the optical fiber of the optical fiber temperature sensor.

Optical fiber temperature sensor 1 and heterotypic compact conductor 2 form built-in optical fiber temperature sensor/compact conductor in the transposition of frame winch, carry out the conductor transposition through the frame winch and realize placing in the tight stranded conductor center of heterotypic in the conductor transposition in, the conductor center is hollow circular for optical fiber temperature sensor 1 place space, the stability of circle in the multiplicable conductor cavity of heterotypic compact conductor, for optical fiber temperature sensor provides stable circular spatial structure, avoid optical fiber impaired when cable accessories connects, avoid optical fiber temperature sensor to receive the conductor extrusion, ensure the stability of conductor structure, guarantee the degree of accuracy of optical fiber sensing. The special-shaped compact conductor 2 comprises a multilayer structure which is sequentially arranged from inside to outside, each layer is twisted into a ring shape by copper single wires with different numbers, after each layer is twisted, the next layer is twisted on the outer side of the upper layer (inner layer), and the number of the single wires of each layer is increased from inside to outside; have supporting role each other, under outer layer single line pressure, the structure is more stable. The copper single wires are of tile-shaped structures.

The insulated wire core consists of a compact conductor with a built-in optical fiber temperature sensor, an insulating layer and a copper shielding layer 7; wherein, the insulating layer is the three-layer crowded completion once altogether, including conductor shield 3, polypropylene insulating layer 4 and insulation shield 5, insulation shield 5 is outer to be formed around the package by one deck semi-conductive area, can prevent that the cable from producing and operating the high temperature condition of process under, the copper wire of copper wire copper tape shielding leads to the fact the damage to insulation shield, improves cable run's security. The semi-conductive belt is formed by one semi-conductive belt winding covering 6, the copper shielding layer 7 is a copper wire and copper strip shielding layer, the copper wire shielding layer is composed of soft copper wires which are loosely wound, the surface of the soft copper wire is tightly wound by the copper strips which are reversely wound, and meanwhile, the outer side of the soft copper wire is wrapped by a wrapping belt in a winding mode.

The optical fiber temperature vibration sensor 10 is arranged between the aluminum wires of the first armor layer 9, one or more optical fiber sensors can be selected to be twisted with the aluminum wires in the placement mode, and the optical fiber temperature vibration sensor and the aluminum wires form a complete armor layer together. The optical fiber temperature vibration sensor 10 is placed on the first armor layer 9, the state of a cable line can be monitored in real time, vibration strength is distinguished by vibration optical fibers when the cable is damaged by external machinery, the vibration optical fibers are sent to the data processing module, namely a server, and the external force strength and possible damage identified by the optical fibers can be timely alarmed according to the external force strength and the possible damage, such as external mechanical damage and falling rocks damage; meanwhile, the optical fiber temperature sensor at the position can monitor the water inlet state of a cable circuit under the state of the outer sheath of the cable (after the cable is fed with water, the temperature of the optical fiber at the water inlet position is reduced gradually from the water inlet point to the two sides), faults of grounding of the shielding layer and the armor layer and the like (the faults can lead the temperature at the point to be increased, the temperature high point of the temperature measuring optical fiber of the armor layer can be identified, and the grounding fault caused by external impact is identified jointly through the vibrating optical fiber). And meanwhile, the optical fiber vibration sensor can be effectively protected from being damaged by being placed at the position.

Referring to fig. 3, a typical structure of the optical fiber temperature vibration sensor 10 is composed of a vibration sensing unit 31, a second temperature sensing unit 32, a second aramid reinforcement 33, a second protection pipe 34, a third armor layer 35, a second aramid reinforcement layer 36 and a second metal woven layer 37, the second protection pipe 34, the third armor layer 35, the second aramid reinforcement layer 36 and the second metal woven layer 37 are sequentially disposed from inside to outside, the vibration sensing unit 31, the second temperature sensing unit 32 and the second aramid reinforcement 33 are disposed in the second protection pipe 34, and the second aramid reinforcement 33 is located at a central position of the entire optical fiber temperature vibration sensor 10. The third armor layer 35 is a spiral steel pipe armor layer. The structure of the optical fiber temperature vibration sensor 10 can be adjusted according to the use scene and the specific requirements.

The vibration sensing unit 31 is composed of two 62.5/125 mu m multimode special optical fibers, the second temperature vibration sensing unit 32 is composed of two 9/125 mu m single mode special optical fibers, the long-term working temperature of the optical fiber sensor is 150 ℃, the short-term working temperature is 250 ℃, the influence of the temperature on the optical fiber attenuation performance of the cable in the production and use processes can be met, and the temperature measurement accuracy is ensured. Meanwhile, the first protection pipe 23 and the second protection pipe 34 are made of PTFE materials, the long-term service temperature of the materials can reach 200-260 ℃, and the melting temperature is 327-342 ℃. The optical fiber temperature sensor is still soft at the temperature of-100 ℃, has the best aging life and the minimum friction coefficient in plastics, and can effectively protect the optical fiber of the optical fiber temperature sensor.

The utility model provides a cable has conductor temperature monitoring, cable vibration monitoring, the outer temperature monitoring of cable and data transmission function, can realize that the damaged cable that leads to of oversheath is intake, fault monitoring functions such as shielding layer and armor ground connection, can effectively improve the current-carrying capacity of cable, improves the utilization ratio and the use value of cable. Meanwhile, the double monitoring of temperature and vibration can effectively prevent the occurrence of cable faults, the functions of sensing and positioning in advance are achieved, the reliability of a cable line is improved, and the safe and stable operation of a power system required by the operation of a high-speed rail is ensured.

Example 2

Referring to fig. 4, a monitoring system of a power cable for an electrified railway includes a current sensor, a current monitoring unit, a temperature monitoring unit, a vibration monitoring unit, a data processing system and server, a display system, and a remote monitor.

The current sensor is connected between the cable and the current monitoring unit in series, the optical fiber temperature sensor 1 is connected with the input end of the temperature monitoring unit, the optical fiber temperature vibration sensor 10 is connected with the input end of the vibration monitoring unit, the output ends of the current monitoring unit, the temperature monitoring unit and the vibration monitoring unit are connected with the data processing module and the server, and the output end of the data processing module is connected with the display unit and the remote monitoring unit.

The current monitoring unit monitors the running current of the cable in real time through the current sensor, collects the running current data and transmits the running current data to the data processing module;

the temperature monitoring unit demodulates and analyzes data collected by the optical fiber temperature sensor 1 arranged in the conductor and the optical fiber temperature sensor of the armor layer to obtain the operating temperature of the conductor, and transmits the temperature data to the data processing module;

the vibration monitoring unit demodulates and analyzes data acquired by the armored layer optical fiber vibration sensor 10 to obtain the vibration condition of the cable, and transmits the vibration data to the data processing module;

the data processing module is used for collecting and analyzing the operating current, the conductor temperature, the armor layer temperature and the cable vibration data and transmitting the data to the server;

the display unit is used for displaying the running state of the cable, the line information, the early warning condition and the like;

the server is used for analyzing and processing the cable state line information and the like according to preset conditions and collected data in the system and analyzing the cable running state;

the remote monitoring unit is connected with the data processing module and the server, calls the processed cable state, information and the like, and can display the cable state, the information and the like on an internet terminal.

The monitoring system simultaneously realizes temperature monitoring and space positioning functions by utilizing a Raman scattering effect and an optical time domain reflection technology, a built-in temperature measuring optical fiber sensor of a conductor can realize the sensing of the conductor temperature of a cable line, the positions of abnormal temperature and abnormal temperature are found, the fault caused by temperature rise of the cable line is prevented, meanwhile, the conductor temperature and a current sensor are obtained by the built-in temperature measuring optical fiber sensor of the conductor to obtain the current-carrying capacity of the cable, the relation between the conductor temperature and the current sensor is further obtained, the current-carrying capacity of the cable can be improved under the design threshold value of the conductor temperature of 105 ℃, and the real state of the cable is provided as a reference under the conditions of high-speed rail speed acceleration and the like. And the second temperature sensing unit in the optical fiber temperature vibration sensor of the aluminum wire armor layer can realize the measurement of the temperature of the cable armor layer, the temperature can reflect the temperature of the outer layer of the cable, and simultaneously, under the conditions that the cable is damaged due to the action of external force and the like, the eddy current caused by multipoint grounding of the armor layer and the shielding layer generates heat, and the cable is subjected to water inflow and the like under the condition that the outer protective layer is damaged.

A first vibration sensing unit in the optical fiber temperature vibration sensor of the aluminum wire armor layer simultaneously realizes the sensing and space positioning functions of vibration events by utilizing the Rayleigh scattering effect and the optical time domain reflection technology of optical fibers. The double monitoring of temperature and vibration can effectively prevent the occurrence of cable faults, and when the current is unchanged and the temperature and vibration are suddenly changed, early warning can be given; when the current change and the temperature change are asynchronous, synchronous early warning is carried out; abrupt changes in system parameters indicate a problem with the cabling that does not immediately lead to a failure of the cable system. Therefore, the sensing and positioning can be carried out in advance, the reliability of a cable line is improved, and the safe operation of a high-speed rail system is ensured.

The optical fiber temperature vibration sensor in the monitoring system simultaneously realizes the sensing and space positioning functions of vibration events by utilizing the Rayleigh scattering effect and the optical time domain reflection technology of the optical fiber, can realize the sensing of the vibration of the cable line, is jointly measured with the temperature monitoring unit, can prevent the cable line from faults caused by external damage in advance, and improves the reliability of the safe operation of the cable line.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided would be apparent to those of skill in the art upon reading the above description. The scope of the present teachings should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the pending claims along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are hereby incorporated by reference for all purposes. The omission in the foregoing claims of any aspect of the subject matter that is disclosed herein is not intended to forego such subject matter, nor should the applicants be construed as having contemplated such subject matter as being part of the disclosed subject matter.

Claims (9)

1. The utility model provides a power cable for electrified railway, its characterized in that, includes optic fibre temperature sensor (1), heterotypic inseparable conductor (2), insulating layer, copper shield (7), isolation layer (8), first armor (9), optic fibre temperature vibration sensor (10) and oversheath (11), optic fibre temperature sensor (1), heterotypic inseparable conductor (2), conductor shield (3), polypropylene insulation layer (4), insulation shield (5), semi-conductive area set gradually from inside to outside around covering (6), copper shield (7), isolation layer (8), first armor (9) and oversheath (11), optic fibre temperature vibration sensor (10) set up in first armor (9).

2. The power cable for electric railway according to claim 1, characterized in that the optical fiber temperature sensor (1) and the profiled compact conductor (2) are stranded.

3. A power cable for electric railways according to claim 1, characterized in that said profiled compact conductor (2) comprises a multilayer annular structure arranged in sequence from inside to outside, each layer of annular structure being obtained by stranding copper single wires.

4. The power cable for electric railways according to claim 1, characterized in that the insulating layer comprises a conductor shield layer (3), a polypropylene insulating layer (4) and an insulating shield layer (5) arranged in this order from the inside to the outside.

5. The power cable for electric railway according to claim 4, wherein the insulating shield layer (5) is wrapped with a semi-conducting tape wrapping layer (6).

6. The power cable for the electrified railway according to claim 1, wherein the optical fiber temperature sensor (1) comprises a first temperature sensing unit (21), a first aramid fiber reinforcement (22), a first protective tube (23), a second armor layer (24), a first aramid fiber reinforcement layer (25) and a first metal woven layer (26), the first protective tube (23), the second armor layer (24), the first aramid fiber reinforcement layer (25) and the first metal woven layer (26) are sequentially arranged from inside to outside, and the first temperature sensing unit (21) and the first aramid fiber reinforcement (22) are both arranged in the first protective tube (23).

7. The power cable for electric railway according to claim 6, wherein the first protective tube (23) is made of PTFE.

8. The power cable for electric railways according to claim 6, characterized in that the first temperature sensing unit (21) comprises two 62.5/125 μm multimode specialty fibers.

9. The power cable for the electrified railway according to claim 1, wherein the optical fiber temperature vibration sensor (10) comprises a vibration sensing unit (31), a second temperature sensing unit (32), a second aramid reinforcement (33), a second protection pipe (34), a third armor layer (35), a second aramid reinforcement layer (36) and a second metal woven layer (37), the second protection pipe (34), the third armor layer (35), the second aramid reinforcement layer (36) and the second metal woven layer (37) are sequentially arranged from inside to outside, and the vibration sensing unit (31), the second temperature sensing unit (32) and the second aramid reinforcement (33) are arranged in the second protection pipe (34).

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