4574 results about "Power cable" patented technology

The invention provides a power cable joint insulation state intelligent monitoring method based on a complex environment. The method belongs to the technical field of power system monitoring, and comprises the steps that related data are collected through multiple means, and the related data comprise environment temperature data, partial discharge signals and temperature distribution images; collected environment parameters and partial discharge signals are input to an intelligent analysis system, preprocessing and feature extraction are carried out, an insulation state prediction model is established based on a machine learning algorithm, and the aging degree and potential fault points of a cable joint insulation layer are predicted according to historical data and real-time monitoring data. Environment temperature data, partial discharge signals and temperature distribution images are collected through multiple means, and an intelligent analysis system and a machine learning algorithm are combined, so that the aging degree and potential fault points of the cable joint insulating layer can be predicted more accurately.

The invention discloses a power cable fault diagnosis and analysis method and system based on multi-source data, and relates to the technical field of diagnosis and analys.During operation of the system, various sensors are installed in a cable and the surrounding environment of the cable, operation data of the power cable are collected in real time, and after the collected multi-source data are preprocessed, the power cable fault diagnosis and analysis method and system based on the multi-source data are obtained. The method comprises the following steps: calculating key diagnosis parameters by using a machine learning algorithm, obtaining a comprehensive fault diagnosis index CDI, comparing the comprehensive fault diagnosis index CDI with a preset first threshold M and a preset second threshold N, obtaining a fault level and outputting a corresponding processing strategy, and carrying out fault point positioning by using a reflected wave method in combination with multi-source data according to fault characteristics and a cable model. And outputting a specific position of a fault point, accurately positioning the fault point in the cable, integrating analysis results of the modules, and automatically generating a cable fault diagnosis report which comprises a fault type, a fault point position, potential risk analysis and maintenance suggestions.

The invention discloses an anti-fracture low-voltage power cable, and relates to the technical field of low-voltage cables, the anti-fracture low-voltage power cable comprises three core bodies, the surfaces of the three core bodies are all sleeved with shielding layers, the surfaces of the shielding layers are wrapped with insulating layers, the outer sides of the three core bodies are sleeved with an inner protection layer, the surface of the inner protection layer is sleeved with a thermal insulation layer, and the thermal insulation layer is wrapped with an outer protection layer. The outer side of the thermal insulation layer is sleeved with an outer protection layer, the surface of the outer protection layer is provided with a sliding protection mechanism, and the inner side of the outer protection layer is provided with a reinforcing anti-breaking mechanism in an embedded manner. And when the cable slides, the outer protection layer is not rubbed with the ground, so that the outer protection layer of the cable is prevented from being rubbed and scraped to influence subsequent normal use, the cable is protected to a certain degree, and impurities such as dust and soil adhered to the surface of the cable in the cable transportation and laying process can be scraped.

The invention belongs to the technical field of fault positioning, and particularly relates to a power cable fault positioning method and system, and the method comprises the steps: obtaining real-time cable current pulse waveform data, fault current pulse waveform data and historical cable operation data; through Haar wavelet and Symlets wavelet analysis, gathering the signal mutation points into a signal mutation point feature set; constructing a threshold intelligent optimization model, and calculating to obtain a current pulse wave head time difference; wave head time is identified by using an RNN-CNN architecture, and a unit distance wave head time transformation value of the whole cable is obtained through fitting; and calculating and correcting a fault distance, and combining the corrected fault distance with the position information of the initial end of the cable, thereby determining the position of a fault point. According to the invention, through deep combination of multi-stage wavelet analysis, the threshold intelligent optimization model and the RNN-CNN architecture, rapid and accurate positioning of the power cable fault is realized, and the fault diagnosis efficiency and accuracy are significantly improved.

The invention provides a power cable joint defect detection method and system based on a digital twin model. The method comprises the following steps: acquiring performance parameters, temperature data and ultrasonic parameters of a cable joint; constructing a cable joint multi-field coupling simulation model according to the physical size material parameters of the cable joint; constructing an objective function according to the performance parameters and the temperature data, interacting data of the multi-field coupling simulation model with data under actual operation conditions through the objective function, and updating a pre-constructed cable joint digital twinborn simulation model to obtain a real-time updated cable joint digital twinborn simulation model; and training and testing the radial basis function neural network based on the output data of the cable joint digital twin simulation model updated in real time to obtain a fault diagnosis model of cable joint temperature and ultrasonic data based on deep learning, and detecting the real-time operation state of the cable joint according to the fault diagnosis model. And predicting a potential fault of the cable joint.

The invention relates to the technical field of power equipment state monitoring, and particularly discloses a power cable electrical performance detection method and system, and the method comprises the steps: synchronously collecting a broadband electromagnetic signal, a mechanical vibration signal and a temperature signal at a cable monitoring point; calculating a wavelet coherence coefficient between the signals through continuous wavelet transform, and constructing a multi-modal coupling tensor fusing amplitude and cross-modal time-frequency correlation characteristics; performing time slicing and high-order singular value decomposition on the tensor to obtain a time-varying core tensor sequence, mapping the time-varying core tensor sequence into a high-dimensional manifold curve, and generating a system state fingerprint by calculating local curvature distribution and topology invariants of the curve; inputting the fingerprints into a pre-trained defect prediction model, and directly outputting defect inoculation probability and evolution stage judgment; according to the method, the limitation that early weak defect detection is not sensitive in a traditional method is broken through, and early warning and accurate diagnosis of cable insulation latent defects are achieved.

The invention relates to the technical field of power transmission, and discloses a composite single-core power cable, comprising: a composite core composed of carbon fibers, glass fibers and a resin matrix containing a self-repairing microcapsule, the self-repairing microcapsule being capable of releasing a repairing monomer and repairing a microcrack when the composite core generates the microcrack; the conductor layer is arranged around the composite core and is composed of an aluminum conductor containing nano graphene; the insulating layer wraps the conductor layer and is made of a temperature-sensitive polymer material; and the outer sheath wraps the insulating layer and is made of a waterproof corrosion-resistant material. The composite core of the cable can recover more than 90% of original strength (the loss of tensile strength after repair is only 3%, which is recovered from 580Ksi to 570Ksi) within 24 hours after microcracks (such as the depth of 10mu m) generated by mechanical stress or fatigue in the operation process, and the self-repairing mechanism does not need manual intervention or external equipment, so that the self-repairing performance is greatly improved. And the sudden failure of the traditional cable caused by micro-damage accumulation is avoided.

The invention provides a power cable comprehensive online monitoring system, and relates to the technical field of data processing, and the system comprises the steps: extracting a partial discharge distribution point set in a multi-dimensional feature fusion data set, and calculating the weight factor of each distribution point; based on the weight factors, a weighted point set concave packet generation algorithm is adopted to construct a partial discharge source probability distribution boundary, and a boundary feature point set is obtained; inputting the boundary feature point set and the multi-dimensional feature fusion data set into a convolution-long and short-term memory hybrid neural network to generate a diagnosis result; and a third-level early warning signal is generated based on a diagnosis result, early warning information is pushed to a remote operation and maintenance terminal and a mobile APP through an MQTT protocol, a digital work order service is automatically triggered to generate a maintenance task, and positioning verification is executed. According to the invention, the accuracy of monitoring and fault diagnosis is improved.

The invention discloses an anti-interference flame-retardant cable, which relates to the technical field of power cables, and is characterized by comprising an outer protection layer consisting of a rubber outer sheath, a metal armor and a protection mechanism, an inner protection layer consisting of a wrapping tape, a fireproof layer and a waterproof insulating layer, and a plurality of groups of guide cores wrapped in the waterproof insulating layer, the rubber outer sheath, the metal armoring and protection mechanism, the wrapping tape, the fireproof layer and the waterproof insulating layer are arranged in sequence from outside to inside, the overall layer of the cable is effectively divided through the protection mechanism formed by a plurality of annular assemblies, and the metal annular seats of the annular assemblies are arranged in the fireproof layer. The annular assemblies can resist the pressure directly generated by the outside of the cable, when torsion is generated outside the cable, the annular seats buffer the external torsion through the springs among the annular seats, the influence on the inner protection layer is reduced to a large extent, in addition, when the cable is connected, the position of the inner protection layer can be finely adjusted through the rotating structures of the annular assemblies, and therefore the stability of the cable is improved. And the connection of the cable is accurate.

The invention relates to the technical field of cable preparation, in particular to an extruded insulation low-voltage power cable and a preparation method thereof.The preparation method comprises the steps that metal wires are twisted into a conductor according to preset twisting parameters, and the conductor is preprocessed; extruding an insulating layer on the surface of the pretreated conductor by using a screw extruder to obtain an insulated wire core; monitoring the diameter of the insulated wire core in real time by using a laser diameter measuring instrument, and determining the fluctuation characteristic type of the diameter of the wire core under a first preset condition; obtaining the eccentricity of the insulating layer and the void ratio between the insulating layer and the conductor; judging the qualification of the extrusion process according to the extrusion comprehensive quality index; under the condition that the extrusion process is unqualified, the qualification of the extrusion process is secondarily judged according to the insulation performance evaluation value; under the condition that the extrusion process is judged to be unqualified for the second time, an adjustment strategy of the extrusion process is determined; and after the insulated wire cores qualified in the extrusion process are twisted into a cable, an outer protective sleeve is extruded. The production efficiency and the product stability of the cable are improved.

The invention relates to the technical field of power equipment state monitoring, and particularly discloses a power cable operation state real-time evaluation system based on multi-mode deep learning, and the system comprises the steps: synchronously collecting the load, partial discharge and temperature strain data of a cable through a current and voltage sensor, an ultrahigh frequency sensor and a distributed optical fiber sensor; feature extraction and cross-dimension fusion are carried out on the multi-source data, and a multi-dimensional feature matrix is constructed; a pre-trained deep learning model is utilized to analyze internal association between the features, and cable health degree scores, fault risk levels and defect type identification results are output; automatically generating and executing a load adjustment, loop switching or precise maintenance strategy according to an evaluation result; according to the method, the problems of inaccurate evaluation and early warning lag caused by data isolation analysis of a traditional monitoring method are solved, and real-time accurate evaluation and intelligent closed-loop operation and maintenance of the operation state of the cable are realized.

The present invention describes an overhead cable spacer device for coupling and keeping them separate from each other. The spacer device has a spacer body and at least four spacer arms coupled to the spacer body. Each of said at least four spacer arms includes an entering portion to receive the overhead cables and at least two retaining elements. One of said at least four spacer arms comprises a hole in its upper portion in which a mechanical rod is coupled in order for the spacer device to be installed from the ground, and a retaining element allows the coupling of the overhead cable, by means of pressure, and the other retaining element prevents the uncoupling of the overhead cable.

The invention relates to the technical field of cables, and provides a fireproof flame-retardant 10kV power cable and a preparation method thereof. The fire-resistant flame-retardant 10kV power cable comprises a conductor and a fire-resistant flame-retardant layer, the fireproof flame-retardant layer is prepared from the following raw materials in parts by weight: 35 to 45 parts of linear low-density polyethylene, 40 to 50 parts of ethylene-vinyl acetate copolymer, 25 to 30 parts of modified aluminum hydroxide, 5 to 8 parts of polyethylene grafted maleic anhydride, 10 to 12 parts of phosphate modified halloysite nanotube, 5 to 8 parts of ZIF-8 loaded zinc borate core-shell particles, 15 to 20 parts of magnesium hydroxide and 2 to 3 parts of silane coupling agent. 0.5 to 1 part of antioxidant, 0.5 to 1 part of calcium stearate and 1 to 1.5 parts of polyethylene wax. According to the cable prepared in the invention, the situation that a conductor is exposed and the fire resistance is lost due to cracking and falling under long-time high-temperature baking is avoided; the continuous effectiveness of the flame retardant at high temperature is improved.

The invention provides a tear-resistant, wear-resistant, low-smoke and non-dripping sheath material as well as a preparation method and application thereof. The tear-resistant wear-resistant low-smoke non-dripping sheath material is prepared from the following components in parts by weight: 25 to 35 parts of metallocene linear low-density polyethylene, 10 to 15 parts of ethylene-vinyl acetate copolymer, 6 to 8 parts of compatilizer, 50 to 60 parts of aluminum hydroxide, 10 to 15 parts of magnesium hydroxide, 3 to 4 parts of microencapsulated red phosphorus, 5 to 8 parts of lithium oxide synergist, 4 to 6 parts of silicone master batch, 0.3 to 0.7 part of carbon black master batch and 1.5 to 2.5 parts of coupling agent. The tear-resistant wear-resistant low-smoke non-dripping sheath material provided by the invention has the characteristics of being halogen-free, flame-retardant, tear-resistant and wear-resistant, and a low-smoke halogen-free flame-retardant power cable prepared from the sheath material has the characteristics of high smoke light transmittance during combustion, no dripping and cracking resistance.

The utility model discloses a pressure-resistant cross-linked polyethylene power cable which comprises an outer sheath, an armor layer, an oxygen isolation inner protection layer and a flame-retardant wrapping tape layer which are sequentially arranged from outside to inside, and a pressure-resistant cable core, a plurality of power cable cores and a plurality of interval units are arranged in the flame-retardant wrapping tape layer. According to the power cable, the oxygen isolation inner protection layer effectively prevents oxygen permeation and delays aging of the cable, and the flame-retardant belting layer improves the fireproof performance of the cable. The multiple surrounding plate bodies surround the pressure-resistant cable core, and the spacing plate bodies play a role in separating and fixing the power cable core, so that the pressure-resistant capability of the cable is improved, and the overall structure of the cable is more compact and stable. In addition, the insulating layer is made of the cross-linked polyethylene material, so that the cable has good insulating performance, short circuit can be effectively prevented, the safety and reliability of the cable are improved, and power transmission is stable and efficient.

The invention discloses a convenient-to-connect medium-voltage cable, and relates to the technical field of power cables, the convenient-to-connect medium-voltage cable comprises a cable body, a plurality of cable cores are installed in the cable body in the circumferential direction at equal angles, a built-in sleeve is installed on the inner side of the cable body, an air bag is installed in the built-in sleeve, and a plurality of ring strips are evenly installed on the outer wall of the built-in sleeve at equal intervals; according to the invention, double dispersion and buffering of external impact pressure can be realized, so that the cable can adapt to a more severe and complicated external environment, the external impact force can be converted into defense force for inhibiting further deformation of the cable body, and the cable can be prevented from being damaged. The external impact force is prevented from being directly applied to the cable core, the cable appearance is endowed with the automatic repairing capability, the cable body can be prevented from being directly and rigidly pulled, the external pulling force and the bending stress can be dispersed in the radial direction of the cable, and more comprehensive and reliable protection on the cable core is achieved.

The invention belongs to the technical field of cable insulation monitoring, and provides a power distribution network cable insulation situation on-line monitoring platform based on equivalent electrical characteristics, which comprises a data acquisition module used for acquiring electrical parameters of cables in a power distribution network in real time; the database module is used for storing historical data, equivalent electrical characteristic model parameters of various insulation defects, insulation situation evaluation reports and correlation analysis results among electrical parameters; the signal processing module is used for combining the data output by the data acquisition module with a database and carrying out correlation analysis; the insulation situation judgment module is used for judging whether the cable has an insulation deterioration trend or not based on the output of the signal processing module in combination with a preset insulation state threshold value; and the alarm module is used for triggering an alarm signal when the insulation situation judgment module detects that the insulation degradation trend exceeds a preset threshold value. According to the scheme, the insulation state of the power cable in operation is evaluated more comprehensively, so that accurate early warning is achieved, and faults are effectively checked.

The invention discloses a power cable tiny defect positioning method based on a CFI-Z algorithm, and the method comprises the steps: obtaining a reflection coefficient vector of a head end of a power cable obtained through sweep frequency signals based on multiple frequencies, and obtaining a minimum norm least square solution and a closed solution of a power cable fault positioning factor according to a continuous frequency-increasing Z transformation matrix; and obtaining the sparse intensity of the minimum norm least square solution and the closed solution to obtain the final solution of the power cable fault positioning factor, and finally obtaining the position of the power cable defect according to the head end reflection time domain sequence of the power cable to complete the positioning of the early defect of the cable. According to the invention, the problems of insufficient high-frequency components and bandwidth limitation in the injected pulse are solved, so that the defect positioning sensitivity of the power cable is high, the anti-noise capability is strong, the positioning error is small especially under the condition of a long cable or a cable with small defects, and the method has a good effect in early-stage small defect positioning.

The invention provides a cable defect detection device based on double-path coupling frequency domain reflection, and belongs to the technical field of power cable detection. Comprising a master control module, a double-path coupling signal generator, a first coupler, a second coupler, a first signal comparator and a second signal comparator, the master control module is electrically connected with the double-path coupling signal generator; the input end of the first coupler is connected with the double-path coupling signal generator, the coupling port of the first coupler is connected with a cable to be tested, the output end of the first coupler is connected with the input end of the first signal comparator, and the output end of the first signal comparator is connected with the input end of the second signal comparator; the input end of the second coupler is connected with the double-path coupling signal generator, and the output end of the second coupler is connected with the second signal comparator; the output end of the first signal comparator and the output end of the second signal comparator are both electrically connected with the master control module. According to the invention, the problem of phase ambiguity of single-path measurement is overcome by using a double-path signal comparison structure, and the accuracy and reliability of cable defect detection are remarkably improved.

The invention relates to the technical field of power monitoring, in particular to an operation state monitoring operation and maintenance method and system for a power cable, and the method comprises the following steps: transmitting a test signal with preset frequency and intensity to a target cable; capturing a test signal transmitted through the cable at the other end of the cable, and predicting the aging degree of the cable through an attenuation index; analyzing the time delay and intensity of a reflected signal in the cable by using a TDR technology, and determining the initial position of potential damage or discontinuity in the cable; performing a multi-frequency signal test on the cable, and analyzing the transmission characteristics of the cable to each frequency signal so as to obtain a fault type; and comprehensively analyzing by using a multi-task learning model to determine the aging condition and the specific damage position of the cable. According to the invention, obvious external damage of the cable can be detected, tiny damage or aging phenomena, invisible to naked eyes, in the cable can be identified, and the requirement of manual operation is reduced, so that the detection efficiency and reliability are improved.

The invention belongs to the technical field of power cable fault positioning. The invention discloses a TDR power cable global fault positioning method based on multi-frequency cooperative excitation and environment adaptive correction. The method comprises the following steps: 1) multi-frequency pulse cooperative injection and signal acquisition; 2) environment parameter dynamic sensing and speed correction: embedding a miniature temperature and humidity sensor and a cable insulation state monitoring unit along the cable at an interval of 500m, and collecting laying environment temperature, humidity and insulation material dielectric constant change data in real time; constructing a dynamic speed correction formula based on a preset environment-dielectric constant correlation model; according to the method, the complex fault positioning precision is improved, the environment and scene adaptability is enhanced, and the troubleshooting efficiency is optimized.

The invention discloses an anti-ultraviolet aging low-voltage power cable, and relates to the technical field of cables, the anti-ultraviolet aging low-voltage power cable comprises a fixed wire core, the fixed wire core is provided with a buffer processing assembly, the buffer processing assembly comprises an inner limit insulation sleeve, and the outer side of the fixed wire core is sleeved with the inner limit insulation sleeve. A plurality of clamping connection grooves are formed in the outer side end of the inner limiting insulation sleeve at equal intervals, a plurality of heat exchange integration frames are clamped to the outer side end of the inner limiting insulation sleeve at equal intervals, and protruding clamping frames are laid at the outer side end of the inner limiting insulation sleeve and one ends of the inner sides of the heat exchange integration frames. The situation of high-temperature aging in the cable caused by unbalanced heat production in the cable and poor heat conduction efficiency is avoided, different deformation in the cable caused by different thermal expansion and cold contraction at different positions is reduced through thermal uniformity, and the situation of dislocation damage in the cable is further reduced in cooperation with elastic stretching and elastic supporting. Therefore, the operation stability of the cable is effectively improved, and the service life of the cable is effectively prolonged.

The invention discloses a power cable convenient for cable butt joint connection, and relates to the technical field of power cables, the power cable comprises two conductors, the outer sides of the conductors are sleeved with neck bushes, and the outer sides of the neck bushes are provided with supporting and traction butt joint mechanisms; the supporting and traction butt joint mechanism comprises a corrugated pipe, a lantern ring, a semi-arc sleeve, a connecting block, an elastic rope, a clamping block, an embedding groove, a clamping groove, an arc-shaped cover, flame-retardant cotton, a heat conduction rubber strip, an iron gauze and a limiting groove, and the corrugated pipe is connected to the outer side of the neck bush in a sleeving mode. Through cooperation of the clamping grooves and the clamping blocks, the semi-arc sleeves are conveniently limited on the outer sides of the lantern rings through the connecting blocks, the splicing convenience is improved, and when two cables need to be in butt joint, the semi-arc sleeves are pulled to move, so that the semi-arc sleeves on the two cables are mutually clamped on the outer sides of the lantern rings of the two cables, and the elastic ropes on the two conductors are forced to be mutually staggered and pulled.

The invention discloses an extruded and insulated flame-retardant power cable for on-line monitoring of rail transit, and relates to the technical field of power cables, serpentine springs are connected between two adjacent cavity frames and outside corresponding five conductors on the outer side, an outer plastic pipe is connected between two adjacent serpentine springs, the outer plastic pipe is filled with silicone fireproof adhesive, and the outer plastic pipe is connected with the outer side of the serpentine springs. According to the invention, through the cooperation of the cavity frame, the serpentine spring, the inner plastic pipe and the expanding and supporting strip, the outer side of the conductor is provided with a sufficient heat dissipation circulation gap, the heat dissipation speed of the cable is improved, and the inner parts of the outer plastic pipe and the inner plastic pipe are filled with silicone fireproof glue, so that the heat dissipation performance of the cable is improved. The silicone fireproof adhesive expands when meeting fire to form a compact fireproof layer which tightly wraps the outer side of the conductor, and the expanded fireproof layer can fill heat dissipation gaps among the conductors to prevent flame from spreading, so that the cable has good heat dissipation capability, and meanwhile, the flame retardant property of the cable is also ensured.

The invention provides a power cable test data identification method and system, and the method comprises the steps: obtaining an electrical signal sequence of a power cable under a plurality of preset test condition combinations, carrying out the space-frequency joint feature decomposition of the electrical signal sequence, and constructing a three-dimensional time-frequency data body comprising a space position, a time sequence and a frequency feature; constructing a dynamic phase space on the basis, reconstructing a state trajectory of each physical segment, calculating a fractal dimension spectrum and a nonlinear divergence coefficient set of the trajectory, and generating a defect evolution characteristic tensor; inputting the defect into a spatio-temporal chaotic mapping network, aligning characteristic evolution paths of different physical segments, and constructing a defect propagation spatio-temporal atlas; and analyzing the fault development trend of each physical segment in the time dimension and the defect diffusion path of each physical segment in the space dimension, and outputting an identification result containing a defect type evolution probability sequence and a three-dimensional position offset field. According to the invention, a more accurate and comprehensive basis is provided for state evaluation and maintenance of the power cable.

The invention relates to a power cable insulation state real-time monitoring and alarm device, and belongs to the technical field of power equipment state monitoring. Comprising a multi-source sensing unit which is installed at a cable body and a joint; the edge computing terminal is fixed in the cable well or the ring main unit; and the cloud early warning platform receives the processing data and outputs an alarm instruction. According to the invention, multi-parameter deep fusion is realized, four-dimensional monitoring of grounding current, temperature, partial discharge and humidity is initiated for the first time, and limitation of a single parameter is broken through; and an insulation health index IHI is proposed, and the insulation deterioration degree is quantitatively evaluated. According to the method, tan delta and IHI are calculated on site through an edge-cloud collaborative architecture edge terminal, so that the data transmission quantity is reduced; the cloud dynamic threshold value is adjusted, and the alarm accuracy is improved. According to the invention, intelligent early warning mechanism three-level alarm linkage protection equipment is arranged; and the self-calibration function ensures long-term reliability.

The invention relates to the technical field of power cables, in particular to a heat-aging-resistant crosslinked polyethylene insulated power cable and a preparation method thereof. The cable comprises conductor wire cores, an insulating layer, a filling layer, a composite function layer, a steel tape armoring layer and a sheath layer from inside to outside. The insulating layer is composed of semi-conductive crosslinked polyethylene, silicone resin, nano montmorillonite and an HALS light stabilizer; the filling layer is composed of plasticized glass fabric, polyphenylene sulfide and rare earth oxide; the composite functional layer sequentially comprises a heat-conducting inner layer, a flame-retardant middle layer and an anti-UV outer layer from inside to outside; the sheath layer is composed of polyolefin, white carbon black, ceramic silicone rubber, a flame retardant, polyethylene wax and an initiator. According to the cable, cross-linked polyethylene and silicone resin are preferably selected as heat-resistant materials, heat conduction / flame retardance / UV resistance / armored multi-layer synergistic protection is achieved, the mechanical barrier performance is improved, meanwhile, damage of thermal stress to internal materials is reduced, comprehensive improvement of thermal aging resistance is achieved, and the cable is suitable for high-temperature, high-humidity and frequent thermal cycle harsh environments.

The invention discloses a co-extrusion shielding medium-voltage power cable, and relates to the technical field of cables, the outer side of an inner reinforcing rope is provided with a supporting flame-retardant assembly, the outer side of the inner reinforcing rope is sleeved with a reinforcing spiral, the outer side of the reinforcing spiral is sleeved with a heat conduction pipe, a flame-retardant bag is installed between adjacent supporting rods, and one side of a heat conduction film is bonded with a flame-retardant silica adhesive tape. According to the invention, the reinforced connecting rods embedded in the reinforced through holes can extrude the supporting rods to deform, so that bending is resisted, and excessive bending deformation is prevented; heat generated in the use process of the cable can be dispersed to other positions of the cable, local overheating of the cable is prevented, influences on other inner conductors are reduced due to various reasons such as cooling, fire extinguishing and keeping away of the inner conductors, it is guaranteed that the cable can work normally for a longer time, and the other normal inner conductors are protected.

The invention relates to the technical field of cable monitoring, in particular to a power cable damage monitoring system and method based on a digital twin model, and the system comprises a data collection module, an optical calculation processing module, a terahertz radar detection module, a digital twin modeling module and an underwater communication module. The optical calculation processing module performs high-frequency parallel processing on the acquired environmental data to generate a three-dimensional damage map of the submarine cable; the terahertz radar detection module obtains echo signals of a submarine cable insulation layer and extracts insulation aging state information. The digital twinborn modeling module constructs a cable digital twinborn model based on the three-dimensional damage map and the aging information, and predicts a fault diffusion path; and the underwater communication module transmits the model data to a target receiving end. According to the system, the insulation aging detection precision and the real-time prediction capability of the submarine cable are improved, and the intelligence and the engineering applicability of the system are enhanced.

According to the power cable multi-defect nondestructive testing method and system based on the broadband impedance spectrum, impedance characteristics of a cable under different frequencies are measured, frequency domain data are converted into time domain data through inverse Fourier transform, and accurate positioning and evaluation of internal defects of the cable are achieved; the invention discloses a power cable multi-defect nondestructive testing method based on a broadband impedance spectrum. The method comprises the following steps: step 1, signal output and acquisition; the method comprises the steps that a broadband impedance spectrum tester is used for outputting a broadband sine wave voltage signal, frequency domain measurement data are collected, and the frequency domain measurement data are impedance data of a cable under different frequencies; 2, carrying out time-frequency conversion; converting the frequency domain measurement data into time domain data through inverse Fourier transform, generating a time-amplitude curve, and analyzing the electrical characteristics of the cable; 3, establishing a defect identification model; analyzing the electrical characteristics of the cable at different frequencies by using the transmission line model, and evaluating the state of the cable; step 4, defect positioning and evaluation; and 5, displaying and analyzing a result.