Intelligent induction flame-retardant power cable

Abstract

This utility model discloses an intelligent induction flame-retardant power cable, relating to the field of fire-resistant and flame-retardant cable technology. It includes: a cable core formed by multiple strands of wire, filler material filling the gaps between the wires, and an outer sheath covering the cable core. The wire core is a three-phase power core. It also includes a temperature-sensing conductor, a temperature-sensing return conductor, and at least two resistance detection devices. A reserved channel is provided in the center of the cable core, and the temperature-sensing conductor and the temperature-sensing return conductor are run parallel to each other within the reserved channel. The resistance detection devices are spaced apart along the cable length. The cable of this utility model integrates the temperature-sensing conductor and the temperature-sensing return conductor in the center of the cable core to form a circuit. By setting resistance detection devices to measure the change in resistance between the temperature-sensing conductors, it determines whether the cable temperature is rising. When the temperature rises to a set value, a circuit breaking signal is triggered, disconnecting the cable circuit and preventing the cable temperature from continuing to rise, thus avoiding cable combustion.

Description

Technical Field

[0001] This utility model belongs to the field of fire-resistant and flame-retardant cable technology, specifically relating to intelligent induction flame-retardant power cables. Background Technology

[0002] Cable fires are one of the main causes of electrical fires today. When a cable is overloaded or short-circuited, a localized high temperature can rapidly be generated, which can easily ignite the cable's insulation layer and surrounding combustibles, leading to a fire.

[0003] Currently, cable flame-retardant technology mainly relies on the application of flame-retardant materials. While these materials can inhibit the spread of combustion to some extent, they are inherently difficult to burn and cannot fundamentally eliminate the ignition source. The most crucial measure remains timely power disconnection in the event of a fault.

[0004] A current type of temperature-sensing cable consists of two conductors sheathed with a special heat-sensitive material. When the ambient temperature rises to a set threshold, the insulation performance of the heat-sensitive material drops sharply, causing a short circuit between the two conductors, thus triggering an alarm signal and disconnecting the power. While this method achieves flame-retardant protection, the heat-sensitive material undergoes irreversible performance changes after activation, meaning the entire temperature-sensing cable can only be used once. To restore the protective function, a new temperature-sensing cable must be replaced, increasing usage and maintenance costs.

[0005] Therefore, there is an urgent need to develop a reusable and continuously effective induction flame-retardant cable to overcome the shortcomings of existing technologies and improve the safety and economy of cable systems. Utility Model Content

[0006] In order to overcome the problems existing in the background technology, this utility model provides an intelligent induction flame-retardant power cable.

[0007] To achieve the above objectives, this utility model is implemented through the following technical solution: an intelligent induction flame-retardant power cable, comprising a cable core formed by twisting multiple wire cores, a filler filling the gaps between the wire cores, and an outer sheath covering the cable core, wherein the wire core is a three-phase power wire core, and also includes a temperature sensing conductor, a temperature sensing return conductor, and at least two resistance detection devices. The cable core has a reserved channel at its center, and the temperature sensing wire and the temperature sensing return wire are run parallel to each other through the reserved channel; The resistance detection devices are spaced apart along the length of the cable. Each of the resistance detection devices has two current output terminals and two voltage detection terminals; its two current output terminals are electrically connected to the temperature sensing wire and the temperature sensing return wire at the same cross-section of the cable, thereby forming an independent current measurement circuit with a section of the temperature sensing wire and the temperature sensing return wire; its two voltage detection terminals are also connected to the temperature sensing wire and the temperature sensing return wire in the circuit, respectively, for detecting the resistance value of the circuit.

[0008] Preferably, the resistance detection device includes a constant current source, a voltage measurement module, a microprocessor, and a communication module; the constant current source is connected to the current output terminal and is used to provide a constant current to the measurement circuit; the voltage measurement module is connected to the voltage detection terminal and is used to measure the voltage across the circuit; the microprocessor is connected to the voltage measurement module and is used to calculate the resistance value based on the constant current and the measured voltage; the communication module is connected to the microprocessor and is used to transmit data or control signals.

[0009] Preferably, the resistance detection device is electrically connected to the temperature sensing wire and the temperature sensing return wire through a piercing clamp.

[0010] Preferably, the outer sheath has a sealed chamber molded at the position of the resistance detection device, and the resistance detection device is fixedly housed in the sealed chamber.

[0011] Preferably, both the temperature-sensing conductor and the temperature-sensing return conductor are nickel-chromium alloys. Preferably, the three-phase power conductors are arranged in a circular array, and the reserved channel is located at the geometric center of this circle.

[0012] Compared with the prior art, the present invention has the following advantages: The cable of the present invention integrates a temperature sensing conductor and a temperature sensing return conductor in the center of the cable core to form a circuit. By setting a resistance detection device to measure the change in resistance between the temperature sensing conductors, it can be determined whether the cable temperature is rising. When the temperature rises to a set value, a circuit breaking signal is triggered to disconnect the cable, thereby preventing the cable temperature from rising further and thus avoiding cable combustion. Multiple resistance detection devices set at intervals can quickly locate the location of the cable with spontaneous combustion risk, making it convenient for electricians to go for maintenance. Attached Figure Description

[0013] Figure 1 System architecture diagram for intelligent induction flame-retardant power cables; Figure 2 This is a connection structure diagram of the resistance testing equipment; Figure 3 This is a cross-sectional structural diagram of an intelligent induction flame-retardant power cable.

[0014] In the diagram: 1. Outer sheath; 2. First phase line; 3. Second phase line; 4. Third phase line; 5. Reserved channel; 6. Temperature sensing wire; 7. Temperature sensing return wire; 8. Thermal grease. Detailed Implementation

[0015] To make the objectives, technical solutions, and beneficial effects of this utility model clearer, the preferred embodiments of this utility model will be described in detail below to facilitate understanding by those skilled in the art.

[0016] Please see Figures 1 to 3 This embodiment provides an intelligent induction flame-retardant power cable, including a cable core formed by stranding multiple conductors, a filler filling the gaps between the conductors, and an outer sheath 1 covering the cable core. The conductors are three-phase power conductors. The filler is glass fiber, and the outer sheath 1 is a low-smoke halogen-free flame-retardant polyolefin sheath. The three-phase power conductors are formed by stranding a first phase conductor 2, a second phase conductor 3, and a third phase conductor 4.

[0017] The cable core has an axially extending reserved channel 5 at its center. Two nickel-chromium alloy conductors, serving as temperature-sensing leads 6 and temperature-sensing return leads 7, run parallel within this channel. Nickel-chromium alloy possesses stable and reusable resistance-temperature characteristics. The first phase conductor 2, the second phase conductor 3, and the third phase conductor 4 are arranged in a circular array, with the reserved channel 5 located at the geometric center of the three-phase power conductor core. The surfaces of the temperature-sensing leads 6 and 7 are covered with insulating material, and the reserved channel 5 is filled with thermally conductive silicone grease 8.

[0018] Resistance testing equipment should be installed at 50-meter intervals along the cable's length. During installation: 1. At the cable installation location, strip the outer sheath 1 to expose the temperature sensing wire 6 and the temperature sensing return wire 7; 2. Use piercing clamps to securely connect the two current output terminals (C+, C-) and the two voltage detection terminals (V+, V-) of the resistance detection device to the temperature sensing lead 6 and the temperature sensing return lead 7, respectively; 3. Place the value detection equipment in a sealed chamber molded on the outer sheath 1 and perform waterproof sealing treatment to ensure its isolation from the environment.

[0019] The working principle of a resistance testing device and its internal modules and workflow are as follows: Constant current output: The constant current source inside the device outputs a constant micro current of 1mA to the circuit consisting of the temperature sensing wire 6 and the temperature sensing return wire 7 through the C+ and C- terminals. Voltage sampling: The high-precision voltage measurement module collects the voltage values ​​at both ends of the 6-loop circuit of the temperature sensing wire in real time through the V+ and V- terminals; Calculation and Judgment: The microprocessor (MCU) calculates the real-time resistance value of the wire segment according to Ohm's law (R=U / I), and then converts it to the corresponding temperature value according to the resistance-temperature relationship formula of nickel-chromium alloy. Signal Output: The microprocessor uploads temperature data to the remote main controller via a communication module (such as an RS-485 bus). If the calculated temperature value exceeds the first threshold (such as 90℃), a warning signal is issued; if it exceeds the second threshold (such as 120℃), a passive dry contact signal is immediately sent to the intelligent circuit breaker connected to the main circuit to drive it to cut off the cable power supply.

[0020] Automatic Recovery: After a power outage, the temperature at the fault point gradually decreases, and the resistance of the temperature sensing wire 6 recovers accordingly. Once the microprocessor continuously monitors and the temperature returns to the normal range, the system automatically resets and re-enters monitoring mode. The entire process requires no component replacement. The overall system workflow is as follows: Normal monitoring status: All resistance detection devices continuously measure and report the cable temperature in their respective areas, and the temperature distribution curve of the entire cable is displayed on the main controller screen.

[0021] Overheat warning status: When the temperature of a certain area rises to 90℃ due to overload, the main controller will issue an audible and visual alarm and accurately locate the overheated section on the screen, reminding maintenance personnel to check for potential hazards.

[0022] Power failure protection status: If the temperature continues to rise to 120℃, the controller will immediately trigger a power failure command, cutting off the power supply and issuing an emergency alarm. Maintenance personnel can quickly reach the precise section for repair based on the location information.

[0023] Automatic recovery: After maintenance and troubleshooting, closing the circuit breaker will restore all system components to their initial state, allowing them to be put back into operation without the need to replace the temperature sensing cable or detection equipment. Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of this utility model.

Claims

1. An intelligent induction flame-retardant power cable, comprising a cable core formed by stranding multiple conductors, a filler filling the gaps between the conductors, and an outer sheath (1) covering the cable core, wherein the conductors are three-phase power conductors, characterized in that: It also includes a temperature sensing lead (6), a temperature sensing return lead (7), and at least two resistance detection devices; The cable core has a reserved channel (5) at its center, and the temperature sensing wire (6) and the temperature sensing return wire (7) are run parallel to each other in the reserved channel (5). The resistance detection devices are spaced apart along the length of the cable. Each of the resistance detection devices has two current output terminals and two voltage detection terminals; its two current output terminals are electrically connected to the temperature sensing wire (6) and the temperature sensing return wire (7) at the same cross section of the cable, thereby forming an independent current measurement circuit with a section of the temperature sensing wire (6) and the temperature sensing return wire (7); its two voltage detection terminals are also connected to the temperature sensing wire (6) and the temperature sensing return wire (7) in the circuit, respectively, for detecting the resistance value of the circuit.

2. The intelligent, inductively flame-retardant power cable of claim 1, wherein, The resistance detection device includes a constant current source, a voltage measurement module, a microprocessor, and a communication module. The constant current source is connected to the current output terminal and is used to provide a constant current to the measurement circuit. The voltage measurement module is connected to the voltage detection terminal and is used to measure the voltage across the circuit. The microprocessor is connected to the voltage measurement module and is used to calculate the resistance value based on the constant current and the measured voltage. The communication module is connected to the microprocessor and is used to transmit data or control signals.

3. The intelligent, inductively flame-retardant power cable of claim 1, wherein, The resistance detection device is electrically connected to the temperature sensing wire (6) and the temperature sensing return wire (7) through a piercing clamp.

4. The intelligent, inductively flame-retardant power cable of claim 1, wherein, The outer sheath (1) has a sealed chamber molded at the position of the corresponding resistance detection device, and the resistance detection device is fixedly housed in the sealed chamber.

5. The intelligent, inductively flame-retardant power cable of claim 1, wherein, Both the temperature sensing wire (6) and the temperature sensing return wire (7) are nickel-chromium alloys.

6. The intelligent, inductively flame-retardant power cable of claim 1, wherein, The three-phase power conductors are arranged in a circular array, and the reserved channel (5) is located at the geometric center of the circle.

Images