Composite insulation low voltage power cable

Abstract

The application discloses a composite insulation low-voltage power cable applied to the field of low-voltage power cables, which comprises a plurality of cable pipes, a wire core is arranged in the cable pipes, a partition ring is arranged at the two ends of the cable pipe, and a sectional sheath is sealingly connected between adjacent partition rings; a fire-retardant pad layer is filled between the cable pipe and the wire core, a reinforced wire harness containing a temperature sensor is arranged in the fire-retardant pad layer; a protection pipeline is connected between the partition rings and adheres to the cable pipe, a fire-retardant gas is filled in the pipeline, sealing joints are arranged at the two ends of the pipeline and are connected with one-way inflation heads, an air pressure sensor is arranged in the inflation head, the sectional structure design is adopted, temperature and air pressure monitoring functions are integrated, real-time data acquisition, analysis and abnormal alarm are realized in combination with an auxiliary protection system, the problems that existing cables lack local temperature and external pressure state monitoring and protection response lag are solved, the temperature and pressure state of each cable pipe of the composite insulation low-voltage power cable are remotely monitored in real time, and protection and alarm can be realized in time in an abnormal state.

Description

Technical Field

[0001] This invention relates to the field of low-voltage power cables, and particularly to a composite insulated low-voltage power cable. Background Technology

[0002] Insulated low-voltage power cables are electrical power transmission and distribution equipment with a rated voltage of 1kV and below, widely used in building power distribution, industrial power supply, municipal engineering, and new energy fields. Their structure typically consists of a conductor (copper / aluminum), an insulation layer, and a protective layer; some models include a shielding layer to enhance anti-interference capabilities. The mainstream insulation materials are polyvinyl chloride (PVC), cross-linked polyethylene (XLPE), and polyethylene (PE).

[0003] Chinese invention CN117877793B discloses an environmentally friendly PP insulated low-voltage cable. During the production of this cable, the conductor is first annealed, and then the insulation layer is extruded around the outer periphery of the conductor through an extruder. Next, a protective sheath is extruded around the outer periphery of the insulation layer through an extruder. Then, the cable is cooled by a cooling module, and the cooling quality is detected and controlled by a cable testing system. The above method can improve the quality of the cable.

[0004] Chinese invention CN119253354B discloses a low-voltage power cable that solves the problem in the prior art where a high current density easily occurs at the junction of two cables, causing the local temperature at the contact point to rise, resulting in a gap between the two cables and affecting the current transmission performance.

[0005] Current low-voltage power cable systems generally suffer from inadequate monitoring capabilities, particularly in the real-time monitoring of abnormal local temperature changes and external mechanical stress. Due to the lack of effective online monitoring methods, the system struggles to detect and issue timely warnings when cables experience localized overheating or strong external pressure. This localized overheating or pressure can easily damage the cable insulation, leading to performance degradation, accelerated aging, and even short-circuit faults, severely impacting the safe and stable operation of the power system. Summary of the Invention

[0006] The core of this invention lies in solving the problems of existing low-voltage power cables lacking real-time monitoring capabilities for localized temperature anomalies and external pressure conditions, and exhibiting delayed protective response when faults occur, by integrating a reinforced wire bundle with an integrated fiber optic temperature sensor and a protective conduit filled with flame-retardant gas, combined with a segmented isolation ring and sheath structural design. Simultaneously, it achieves precise remote monitoring of the operating temperature of each section of the cable core and its external pressure conditions.

[0007] To solve the above problems, the present invention adopts the following technical solution.

[0008] A composite insulated low-voltage power cable includes multiple cable tubes, with wire cores threaded between the multiple cable tubes. Both ends of the cable tubes are fixedly connected to isolation rings, and segmented sheaths are sealed and snapped between adjacent isolation rings. A flame-retardant pad is filled between the cable tubes and the wire cores, and multiple reinforcing wire bundles distributed around the cable tubes are embedded in the flame-retardant pad. At least one reinforcing wire bundle contains multiple uniformly distributed temperature sensors.

[0009] The isolation ring includes an outer ring body that matches the end face of the cable conduit, and an inner ring body connected inside the outer ring body. The inner ring body has through holes that match the reinforcing wire harness. The segmented sheath includes a protective shell with an air inlet and a data acquisition unit. A wiring ring for connecting multiple reinforcing wire harnesses is fixedly connected to the inner wall of the protective shell. Multiple evenly distributed protective lines are connected between the outer ring bodies at both ends of the cable conduit, and the protective lines are in contact with the surface of the cable conduit.

[0010] The protective pipeline includes a flexible tube filled with flame-retardant gas, with sealing joints connected to both ends of the tube. A one-way inflation head is fixedly connected to the inner ring and inserted into the sealing joint. A pressure sensor is installed inside the one-way inflation head. Multiple air tubes are fixedly connected to the side wall of the protective shell. A flow guide hole matching the air tubes and communicating with the one-way inflation head is opened on the outer ring. The air tubes are used for fixing the outer ring and for airflow delivery.

[0011] Furthermore, one end of the reinforced wiring harness located within the segmented sheath is connected to a terminal block that is electrically connected to the temperature sensor, and the terminal block is connected to the wiring ring via a flexible wire.

[0012] Furthermore, an insulating protective sleeve that engages with the conductor is snapped between the two partition rings on both sides of the segmented sheath.

[0013] Furthermore, a protective film covering multiple protective pipelines is connected between the isolation rings at both ends of the cable conduit.

[0014] Furthermore, the temperature sensor is a fiber optic temperature sensor, and multiple evenly distributed heat-conducting units are fixedly connected to one end of the reinforcing wire bundle near the core.

[0015] Furthermore, a pad is connected to one end of the flexible hose near the cable conduit, and the surface of the pad has anti-slip texture.

[0016] Furthermore, the inner ring is provided with an air guide channel that communicates with multiple one-way inflation heads. The airflow output from the air pipe is delivered to each one-way inflation head through the air guide channel and then enters each protective pipeline.

[0017] Furthermore, the one-way inflation head includes a docking interface that matches the sealing connector. A hollow ring that communicates with the air pipe and matches the opening end of the sealing connector is installed inside the docking interface. A valve cover is inserted into the hollow ring. A compression spring is connected between the inner walls of the hollow ring on the valve cover. A pressure sensor is installed on the valve cover.

[0018] Furthermore, it also includes an auxiliary protection system, which is connected to a monitoring module, a data processing module, a data storage module, and an alarm module;

[0019] The monitoring module is used to collect and integrate temperature data from the temperature sensor inside the reinforced wire harness and air pressure data collected by the air pressure sensor in real time.

[0020] The data processing module is used to analyze and calculate the data acquired by the monitoring module, including temperature trend prediction, pressure anomaly threshold comparison and pattern recognition;

[0021] The data storage module is used to store historical monitoring data, analysis reports, and system configuration parameters, and supports data backtracking and remote querying;

[0022] The alarm module is used to automatically trigger audible and visual alarm signals and preset protection workflows when the data processing module detects that the temperature exceeds the preset safety range or the air pressure is continuously abnormal.

[0023] Compared with the prior art, the advantages of this invention are:

[0024] (1) This solution, through the segmented sheath and isolation ring design of the cable, not only achieves good sealing and insulation protection, but also facilitates the installation and maintenance of the cable; the flame-retardant gas filled in the protective pipeline not only provides pressure detection function, but also enhances the flame-retardant performance of the cable, improves the safety of the cable in complex environments, effectively reduces the risk of failure caused by excessive temperature or abnormal external pressure, extends the service life of the cable, and provides a strong guarantee for the reliable operation of the power system.

[0025] (2) It can realize real-time monitoring and intelligent protection of cable operation status. Through the coordinated work of components such as integrated monitoring module and data processing module, it can effectively prevent potential faults. Attached Figure Description

[0026] Figure 1 This is a perspective view of the cable of the present invention;

[0027] Figure 2 This is a schematic diagram of the segmented sheath and the partition ring in their disassembled state according to the present invention;

[0028] Figure 3 This is a side sectional view of the present invention;

[0029] Figure 4 for Figure 3 Schematic diagram of the structure at point A;

[0030] Figure 5 This is a cross-sectional view of the present invention;

[0031] Figure 6for Figure 5 Schematic diagram of the structure at point B;

[0032] Figure 7 This is a schematic diagram showing the connection between the system and the cable of the present invention.

[0033] Explanation of the labels in the diagram:

[0034] 1. Cable conduit; 2. Wire core; 3. Isolation ring; 31. Outer ring body; 32. Inner ring body; 321. Inflation head; 322. Pressure sensor; 4. Segmented sheath; 41. Protective shell; 411. Air tube; 42. Connecting ring; 5. Protective pipeline; 51. Flexible hose; 52. Sealing joint; 53. Gasket; 6. Reinforced wire harness. Detailed Implementation

[0035] The technical solutions will now be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention.

[0036] First implementation method:

[0037] Please see Figures 1-6 A composite insulated low-voltage power cable includes multiple cable conduits 1, with conductors 2 threaded between the cable conduits 1. Both ends of each cable conduit 1 are fixedly connected to a partition ring 3, and a segmented sheath 4 is sealed between adjacent partition rings 3. A flame-retardant padding layer is filled between the cable conduits 1 and the conductors 2. Multiple reinforcing wire bundles 6, distributed around the cable conduits 1, are embedded within the flame-retardant padding layer. At least one reinforcing wire bundle 6 contains multiple uniformly distributed temperature sensors. The temperature sensors are fiber optic temperature sensors, and a suitable temperature sensor from the prior art, such as HKS-T400, can be selected and configured by those skilled in the art.

[0038] Multiple evenly distributed heat-conducting units are fixedly connected to one end of the reinforced wire harness 6 near the wire core 2. The heat-conducting units are metal foil sheets or silicone heat-conducting pads. The heat of the wire core 2 is transferred to the temperature sensor inside the reinforced wire harness 6 through the heat-conducting units. One end of the reinforced wire harness 6 located inside the segmented sheath 4 is connected to a terminal that is electrically connected to the temperature sensor. The terminal is connected to the terminal ring 42 through a flexible wire.

[0039] An insulating protective sleeve that engages with the conductor core 2 is snapped between the two partition rings 3 on both sides of the segmented sheath 4. The segmented sheath 4 is connected to the cable support;

[0040] The isolation ring 3 includes an outer ring body 31 that matches the end face of the cable tube 1, and an inner ring body 32 connected inside the outer ring body 31. The inner ring body 32 has a through hole that matches the reinforcing wire harness 6. The segmented sheath 4 includes a protective shell 41 with an air inlet and a data acquisition unit. A wiring ring 42 for connecting multiple reinforcing wire harnesses 6 is fixedly connected to the inner wall of the protective shell 41. Multiple evenly distributed protective conduits 5 are connected between the outer ring bodies 31 at both ends of the cable tube 1, and the protective conduits 5 are in contact with the surface of the cable tube 1.

[0041] The protective pipeline 5 includes a flexible tube 51 filled with flame-retardant gas. Both ends of the flexible tube 51 are connected to sealing joints 52. A pad 53 is connected to the end of the flexible tube 51 near the cable conduit 1. The pad 53 has anti-slip texture on its surface and is used to help stabilize the protective pipeline 5 under pressure.

[0042] Optionally, a protective film covering multiple protective conduits 5 is connected between the isolation rings 3 at both ends of the cable conduit 1.

[0043] A one-way inflation head 321 with an insertion sealing connector 52 is fixedly connected to the inner ring body 32, and a pressure sensor 322 is installed inside the one-way inflation head 321; multiple air tubes 411 are fixedly connected to the side wall of the protective shell 41, and an air guide channel communicating with multiple one-way inflation heads 321 is opened in the inner ring body 32; the pressure sensor 322 adopts the prior art, and a suitable sensor in the prior art can be selected and set by those skilled in the art, such as LFC-19;

[0044] The outer ring 31 is provided with a flow guide hole that matches the air tube 411 and communicates with the one-way inflation head 321; after the air tube 411 is inserted into the flow guide hole, it is used to fix the outer ring 31 and transport the airflow to the one-way inflation head 321; the airflow output from the air tube 411 is transported to each one-way inflation head 321 through the air guide channel, and then enters each protective pipeline 5.

[0045] During the inflation process, the pressure sensor 322 values ​​at each protective pipeline 5 are detected to determine whether each protective pipeline 5 has been fully inflated. If the pressure sensor 322 of a protective pipeline 5 still fails to reach the set value after the inflation time has exceeded the set time, it is determined that the protective pipeline 5 is leaking.

[0046] The data acquisition unit set on the segmented sheath 4 is connected to the wiring ring 42 and is used to collect data from each reinforcing wire harness 6; the air inlet set on the segmented sheath 4 is connected to an external air inlet device, and the air inlet device is connected to a gas tank for storing flame-retardant gas. The air inlet device is used to deliver flame-retardant gas to the gas pipe 411. The air inlet device adopts existing technology, and a suitable air inlet device in the existing technology is selected and installed by a person skilled in the art.

[0047] When the cable is subjected to external pressure, the protective conduit 5 is compressed, causing the gas inside to be squeezed towards the sealing joint 52, which in turn pressurizes the pressure sensor 322, thereby increasing the pressure value detected by the pressure sensor 322. By detecting the change in pressure value, the pressure status of each section of the cable conduit 1 is determined.

[0048] By detecting the temperature data of the core 2 of the reinforcing wire harness 6 and the air pressure data collected by the air pressure sensor 322, the pressure and temperature status of each section of the cable tube 1 can be determined, so as to remotely monitor the working status of the cable.

[0049] In this embodiment, during cable operation: the fiber optic temperature sensor monitors the operating temperature of the core 2 in real time and transmits the temperature data to the connector 42 via the fiber optic cable within the reinforced wire bundle 6, ultimately being acquired by the data acquisition unit. Simultaneously, when the cable is subjected to external pressure, the pressure acts on the protective conduit 5, pressurizing the flame-retardant gas within the flexible hose 51. The pressurized gas transmits pressure to the one-way inflation head 321 through the sealing connector 52, triggering the pressure sensor 322. The pressure change data detected by the pressure sensor 322 is also transmitted to the data acquisition unit via a line or wireless means near the gas guide channel.

[0050] The data acquisition unit analyzes and processes the collected temperature and air pressure data from each section of cable conduit 1, and provides real-time feedback on the cable's operating status. If an abnormal temperature rise is detected in a section of cable conduit 1 or if the air pressure sensor 322 detects a continuous abnormal pressure, the inflation device can be controlled to operate, supplying flame-retardant gas to the protective pipeline 5 through the air pipe 411 to maintain its internal reference air pressure, ensuring the stability of the pressure monitoring function and the protective effect.

[0051] This solution enables real-time remote monitoring of the temperature and pressure status of each section of the composite insulated low-voltage power cable conduit 1. When abnormal temperature of the conductor 2 or abnormal pressure of the conduit 1 is detected, timely measures can be taken, such as replenishing flame-retardant gas, to ensure the stable operation of the cable. At the same time, the segmented sheath 4 and the isolation ring 3 of the cable not only provide good sealing and insulation protection, but also facilitate the installation and maintenance of the cable. The flame-retardant gas filled in the protective conduit 5 provides pressure detection function while also enhancing the flame-retardant performance of the cable, improving the safety of the cable in complex environments, effectively reducing the risk of failure caused by excessive temperature or abnormal external pressure, extending the service life of the cable, and providing strong support for the reliable operation of the power system.

[0052] Second implementation method:

[0053] It also includes an auxiliary protection system, which is connected to a monitoring module, a data processing module, a data storage module, and an alarm module;

[0054] The monitoring module is used to collect and integrate temperature data from the temperature sensor inside the reinforced wire harness 6 and air pressure data collected by the air pressure sensor 322 in real time. Optionally, the monitoring module can also monitor the current or voltage parameters of the wire core 2.

[0055] The data processing module is used to analyze and calculate the data acquired by the monitoring module, including temperature trend prediction, pressure anomaly threshold comparison and pattern recognition;

[0056] The data storage module is used to store historical monitoring data, analysis reports, and system configuration parameters, and supports data backtracking and remote querying;

[0057] The alarm module is used to automatically trigger an audible and visual alarm signal and a preset protection workflow when the data processing module detects that the temperature exceeds the preset safety range or the air pressure is continuously abnormal. The preset protection workflow includes, for example, controlling the inflation device to replenish air to the protection pipeline 5, or over-inflating for flame retardant protection.

[0058] The auxiliary protection system synchronizes data with the data acquisition unit on the segmented sheath 4 via a wireless or wired interface, ensuring that the monitoring module can receive sensor feedback from each cable pipe 1 in real time, and integrates the control logic of the inflation device. When the air pressure is lower than the set benchmark, the inflation process is automatically started to improve the active protection capability of the cable.

[0059] When the temperature of the core 2 detected in any cable conduit 1 is higher than the maximum set value or when it is burning, the inflation device is set to standby state, and the data changes of the air pressure sensor 322 on the protective pipeline 5 on the cable conduit 1 are collected in real time. If the protective pipeline 5 is burned and damaged, the leakage of the flame-retardant gas inside it will play a certain role in suppressing the flame.

[0060] At the same time, the pressure sensor 322 detects a drop in gas pressure in the protective pipeline 5. At this time, the inflation device is controlled to work, inputting flame-retardant gas into the protective pipeline 5, so that the flame-retardant gas enters the leaking protective pipeline 5 and outputs flame-retardant gas outward, further achieving the flame-retardant effect.

[0061] This implementation method enables real-time monitoring and intelligent protection of cable operating status. Through the coordinated work of components such as the integrated monitoring module and data processing module, potential faults can be effectively prevented. For example, when the temperature is abnormal or the air pressure drops, the system can automatically trigger the injection of flame-retardant gas to suppress the spread of flames, and work with the alarm module to notify maintenance personnel in a timely manner, significantly improving the reliability and safety of the power system. At the same time, the data storage module supports historical data backtracking, which facilitates trend analysis and optimization of maintenance strategies.

[0062] The above description is merely a preferred embodiment of the present invention; it encompasses all the protection scope of the present invention. Any equivalent substitutions or modifications made by those skilled in the art within the technical scope disclosed in the present invention, based on the technical solutions and improved concepts of the present invention, should be covered within the protection scope of the present invention.

Claims

1. A composite insulated low-voltage power cable, comprising multiple cable conduits (1), wherein wire cores (2) are threaded between the multiple cable conduits (1), characterized in that: Both ends of the cable tube (1) are fixedly connected with partition rings (3), and a segmented sheath (4) is sealed between two adjacent partition rings (3); a flame-retardant pad is filled between the cable tube (1) and the wire core (2), and multiple reinforcing wire bundles (6) distributed around the cable tube (1) are embedded in the flame-retardant pad, and at least one of the reinforcing wire bundles (6) is equipped with multiple uniformly distributed temperature sensors. The isolation ring (3) includes an outer ring body (31) that matches the end face of the cable tube (1), and an inner ring body (32) is connected inside the outer ring body (31). The inner ring body (32) has a through hole that matches the reinforcing wire harness (6). The segmented sheath (4) includes a protective shell (41) with an air inlet and a data acquisition unit. A wiring ring (42) for connecting to multiple reinforcing wire harnesses (6) is fixedly connected to the inner wall of the protective shell (41). Multiple evenly distributed protective pipelines (5) are connected between the outer ring bodies (31) at both ends of the cable tube (1). The protective pipeline (5) includes a flexible tube (51) filled with flame-retardant gas. Both ends of the flexible tube (51) are connected to sealing joints (52). A one-way inflation head (321) inserted into the sealing joint (52) is fixedly connected to the inner ring (32). A pressure sensor (322) is installed inside the one-way inflation head (321). Multiple air tubes (411) are fixedly connected to the side wall of the protective shell (41). A flow guide hole matching the air tubes (411) and communicating with the one-way inflation head (321) is opened on the outer ring (31).

2. The composite insulated low-voltage power cable according to claim 1, characterized in that: The reinforced wire harness (6) has a terminal block that is electrically connected to the temperature sensor at one end inside the segmented sheath (4). The terminal block is connected to the wiring ring (42) via a flexible wire.

3. The composite insulated low-voltage power cable according to claim 2, characterized in that: An insulating protective sleeve that is fitted to the wire core (2) is snapped between the two partition rings (3) on both sides of the segmented sheath (4).

4. The composite insulated low-voltage power cable according to claim 1, characterized in that: A protective film covering multiple protective pipelines (5) is connected between the isolation rings (3) at both ends of the cable conduit (1).

5. A composite insulated low-voltage power cable according to claim 1, characterized in that: The temperature sensor is an optical fiber temperature sensor, and the end of the reinforcing wire bundle (6) near the wire core (2) is fixedly connected with multiple uniformly distributed heat-conducting units.

6. The composite insulated low-voltage power cable according to claim 1, characterized in that: The flexible tube (51) is connected to a pad (53) at one end near the cable tube (1), and the surface of the pad (53) is provided with anti-slip texture.

7. A composite insulated low-voltage power cable according to claim 1, characterized in that: The inner ring (32) has an air guide channel that communicates with multiple one-way inflation heads (321). The airflow output from the air pipe (411) is delivered to each one-way inflation head (321) through the air guide channel and then enters each protective pipeline (5).

8. A composite insulated low-voltage power cable according to claim 1, characterized in that: The one-way inflation head (321) includes a docking interface that matches the sealing connector (52). A hollow ring that communicates with the air pipe (411) and matches the opening end of the sealing connector (52) is installed in the docking interface. A valve cover is inserted into the hollow ring. A compression spring is connected between the inner walls of the hollow ring on the valve cover. The air pressure sensor (322) is installed on the valve cover.

9. A composite insulated low-voltage power cable according to any one of claims 1-8, characterized in that: It also includes an auxiliary protection system, which is equipped with a monitoring module, a data processing module, a data storage module, and an alarm module. The monitoring module is used to collect and integrate temperature data from the temperature sensor inside the reinforced wire harness (6) and air pressure data collected by the air pressure sensor (322) in real time; The data processing module is used to analyze and calculate the data acquired by the monitoring module, including temperature trend prediction, pressure anomaly threshold comparison and pattern recognition. The data storage module is used to store historical monitoring data, analysis reports and system configuration parameters, and supports data backtracking and remote querying. The alarm module is used to automatically trigger an audible and visual alarm signal and a preset protection workflow when the data processing module detects that the temperature exceeds the preset safety range or the air pressure is continuously abnormal.

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