Intelligent cable system for feeding back detection information

Abstract

The invention discloses an intelligent cable system for feeding back detection information, which is applied to a metal cable trough box cable laying occasion. Comprising TEV + ultrasonic sensor modules arranged at equal intervals along the trend of a cable, ultrahigh frequency sensor modules arranged at equal intervals along the trend of the cable, surface acoustic wave sensor modules arranged at equal intervals along the trend of the cable and arranged on the surface of a cable head, and a temperature and humidity sensor module, information collected by the sensor on site is gathered by the signal gathering module and transmitted to a computer data processing background for processing, and then detection information and fault judgment prompts are fed back, so that the problem that the cable laid in the metal groove box cannot be comprehensively and accurately detected is solved. Through the intelligent cable system, more comprehensive cable operation prompt information can be provided for maintenance personnel, fault positioning and troubleshooting are more convenient, and safe operation of some cables bearing important loads can be better guaranteed.

Description

Technical Field

[0001] The invention relates to the field of online cable detection, in particular to the field of online cable detection laid in a metal cable trough box. Background Art

[0002] Cables are often laid in metal cable troughs. Some cables that bear important loads are usually laid in this way, and are often laid together with other cables, resulting in complicated operation. In the prior art, optical fiber temperature measurement is used to detect the operation of cables in metal cable troughs. Optical fiber temperature measurement itself has the risk of optical fiber breakage, and it is difficult to detect partial discharge of cables in time through optical fiber temperature measurement. TEV detection (transient voltage detection to ground) is also used, but oxidation or arc burns on the contact surface of the cable connector increase the contact resistance, resulting in an increase in operating temperature that cannot be detected by partial discharge detection equipment. In addition, TEV detection is greatly interfered with in a strong magnetic field environment and is prone to misjudgment, or partial discharge signals are buried in strong interference and are not effectively detected. Moreover, the bandwidth of TEV detection is usually 3M-100MHz, and it is relatively slow to detect 300MHz-3GHz electromagnetic waves caused by breakdown failures. Cable heads sometimes have surface discharge, which can easily develop into breakdown failures, while TEV detection is insensitive to surface discharge. When a fault occurs, the entire cable is often checked, which affects efficiency. In the existing technology, it is often impossible to conduct comprehensive and accurate inspections on cables laid in metal troughs, and it is also impossible to locate the fault within a small section of the cable. For some cables that carry important loads, if hidden faults cannot be fully and accurately detected, it is easy to develop into a major accident with a wide impact. Summary of the invention

[0003] In order to solve the problems raised in the above background technology, an intelligent cable system for feeding back detection information is proposed. The intelligent cable system is applied to the occasion of laying cables in metal cable trough boxes.

[0004] To achieve the above purpose, the present invention provides the following technical solutions: an intelligent cable system that feeds back detection information. TEV detection is based on Maxwell's electromagnetic field theory to detect the induction current generated by the partial discharge electromagnetic waves of the cable on the surface of the equipment. There is wave impedance on the surface of the equipment, and then a transient voltage to the ground is formed on the outer layer of the equipment. However, the signal spectrum excited by the surface discharge of some cable heads is low and easily interfered by the surrounding magnetic field. It is difficult to detect TEV detection. These surface discharges usually excite 20kHz-60kHz ultrasonic waves at the same time, so this solution adopts a sensor module integrating TEV+ultrasonic detection. During installation, the TEV+ultrasonic sensor is installed close to the outer wall of the metal cable trough box, and the cable trough box should be well grounded to provide a voltage to the ground. The insulation strength and breakdown field strength in the cable insulator are very high. When a breakdown fault occurs, the process progresses very quickly, and a very steep pulse current will be generated, with a rise time of less than 1ns, and 300MHz-3GHz ultra-high frequency electromagnetic waves will be excited. These ultra-high frequency electromagnetic waves are difficult to be detected by TEV detection. This solution also uses an ultra-high frequency sensor module to make up for the shortcomings of TEV detection. During installation, the UHF sensor is installed on the inner wall of the metal cable trough box. During the operation of the cable, even if no partial discharge occurs, the temperature of the cable head increases due to the contact resistance of the cable joint and the temperature of the cable increases due to overload, which cannot be detected by TEV detection, ultrasonic detection and UHF detection. This solution also uses SAW surface acoustic wave sensor module, which is a passive wireless module. It does not need to provide power and battery separately. It is easy to arrange and can be close to the cable joint and non-joint. The temperature and humidity around the cable are also very important factors affecting the safe operation of the cable. This solution also uses temperature and humidity sensor module to provide the operation and maintenance personnel with the temperature and humidity of the cable operation environment in time. The TEV+ ultrasonic sensor signal is collected by the RF signal acquisition module, the SAW surface acoustic wave sensor module signal is received by the wireless signal receiving module, the temperature and humidity sensor module has a built-in A / D converter and transmits the signal to the signal aggregation and transmission module after signal processing. The signal aggregation and transmission module collects the signals of the RF signal acquisition module, the wireless signal receiving module and the temperature and humidity sensor module and transmits them to the computer data processing background. Due to the various interferences and noises around the cable itself under normal conditions, some useful signals are easily buried by these interferences and noises and are not detected. During system debugging, these interference and noise values ​​should be measured, and corresponding filters should be set up in the computer data processing background for filtering. The computer data processing background processes the information transmitted by all downstream sensors, and after processing, it feeds back the detection information and fault judgment prompts to the operation and maintenance personnel. When troubleshooting cable faults, the operation and maintenance personnel often troubleshoot the entire cable, which is inefficient.In this solution, TEV+ ultrasonic sensor modules, UHF sensor modules and SAW surface acoustic wave sensor modules are arranged at equal distances along the cable. The surface acoustic wave sensor module is also installed close to the surface of the cable head. When partial discharge, breakdown, or overheating of the cable occurs, the fault location can be determined and locked within a small section of the cable based on the feedback detection information of each sensor module. The temperature and humidity sensor modules are arranged and installed according to the space conditions.

[0005] Since the electromagnetic interference on site is relatively complex, preferably, the TEV+ultrasonic sensor module is connected to the radio frequency signal acquisition module by a radio frequency coaxial cable with a characteristic impedance of 50Ω.

[0006] Preferably, the UHF sensor module and the RF signal acquisition module are connected by a RF coaxial cable with a characteristic impedance of 50Ω.

[0007] Preferably, the temperature and humidity sensor module is connected to the signal convergence and transmission module using optical fiber.

[0008] Preferably, the wireless signal receiving module and the signal aggregation and transmission module are connected by optical fiber.

[0009] Preferably, the signal aggregation transmission module and the computer data processing background use single-mode optical fiber.

[0010] The beneficial effect of the technical solution is: by simultaneously arranging the TEV+ultrasonic sensor module, the ultra-high frequency sensor module, the SAW surface acoustic wave sensor module, and the temperature and humidity sensor module, comprehensive and accurate detection of cables laid inside metal can be achieved, and the TEV+ultrasonic sensor module, the ultrasonic sensor module, and the SAW surface acoustic wave sensor module are arranged equidistantly along the direction of the cable, which is convenient for locking the range of the fault point, improving the work efficiency of maintenance personnel, and ensuring the safe operation of some cables carrying important loads. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A schematic block diagram of the connection of the system of the present invention; DETAILED DESCRIPTION

[0012] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0013] like Figure 1As shown, the present invention is applied to an intelligent cable system for feedback detection information in the case of laying cables in a metal cable trough box, comprising TEV+ ultrasonic sensor modules arranged at equal distances along the direction of the cable, UHF sensor modules arranged at equal distances along the direction of the cable, SAW surface acoustic wave sensor modules arranged at equal distances along the direction of the cable, and temperature and humidity sensor modules, wherein the SAW surface acoustic wave sensor modules are arranged at equal distances and are additionally provided on the surface of the cable head. The cable partial discharge signal detected by the TEV+ ultrasonic sensor module and the ultrasonic signal excited by the surface discharge are transmitted to the RF signal acquisition module via the RF coaxial cable, and the cable breakdown signal detected by the UHF sensor module is also transmitted to the RF signal acquisition module via the RF coaxial cable. The RF signal acquisition module collects the signal and transmits it to the signal convergence transmission module after A / D conversion. The temperature rise signal at the cable head and non-cable head is collected and wirelessly transmitted to the wireless signal receiving module via the SAW surface acoustic wave, and is received by the wireless signal receiving module and transmitted to the signal convergence transmission module via the optical fiber after A / D conversion. The temperature and humidity of the surrounding environment of the cable trough box are collected by the temperature and humidity sensor module and transmitted to the signal convergence transmission module via the optical fiber after A / D conversion. The signal aggregation and transmission module gathers and collects various signals transmitted from downstream and transmits them to the computer data processing unit via single-mode optical fiber. The computer data processing unit filters out the background signal noise under normal conditions and makes judgments, and feeds back detection information and fault judgment prompts to the operation and maintenance personnel, so that the operation and maintenance personnel can make further processing.

Claims

1. An intelligent cable system for feeding back detection information, characterized in that: It includes a TEV+ultrasonic sensor module, an ultra-high frequency sensor module, a SAW surface acoustic wave sensor module, a temperature and humidity sensor module, a wireless signal receiving module, a radio frequency signal acquisition module, a signal convergence transmission module, and a computer data processing background. The TEV+ultrasonic sensor module is installed equidistantly along the direction of the cable and close to the outer wall of the metal cable trough box. The ultra-high frequency sensor module is installed equidistantly along the direction of the cable and close to the inner wall of the metal cable trough box. The SAW surface acoustic wave sensor module is equidistantly along the direction of the cable and close to the non-cable head surface of the cable laid in the metal cable trough box and is installed on the cable head surface. The temperature and humidity sensor module is installed close to the outer surface of the metal cable trough box, and the cable trough box is grounded. The computer data processing background is connected to the signal convergence transmission module in communication, the wireless signal receiving module is connected to the signal convergence transmission module in communication, and the radio frequency signal acquisition module is connected to the signal convergence transmission module in communication. The temperature and humidity sensor module is communicatively connected with the signal convergence and transmission module, the TEV+ultrasonic sensor module is communicatively connected with the radio frequency signal acquisition module, the ultra-high frequency sensor module is communicatively connected with the radio frequency signal acquisition module, the SAW surface acoustic wave sensor module is wirelessly connected with the wireless signal receiving module, the radio frequency signal acquisition module acquires the radio frequency signals of the TEV+ultrasonic sensor and the ultra-high frequency sensor module and transmits them to the signal convergence and transmission module after processing, the wireless signal receiving module receives the signal of the surface acoustic wave sensor module and transmits it to the signal convergence and transmission module after processing, the temperature and humidity sensor module has a built-in A / D converter and transmits the signal to the signal convergence and transmission module after processing, the signal convergence and transmission module processes the received signal and transmits it to the computer data processing background, the computer data processing background filters out the background signal noise under normal conditions and makes a judgment, and feeds back the detection information and fault judgment prompt.

2. The intelligent cable system according to claim 1, characterized in that: The TEV+ultrasonic sensor module is connected to the radio frequency signal acquisition module using a radio frequency coaxial cable with a characteristic impedance of 50Ω.

3. The intelligent cable system according to claim 1, characterized in that: The UHF sensor module is connected to the radio frequency signal acquisition module by a radio frequency coaxial cable with a characteristic impedance of 50Ω.

4. The intelligent cable system according to claim 1, characterized in that: The temperature and humidity sensor module is connected to the signal convergence and transmission module using an optical fiber.

5. The intelligent cable system according to claim 1, characterized in that: The wireless signal receiving module and the signal aggregation and transmission module are connected by optical fiber.

6. The intelligent cable system according to claim 1, characterized in that: The signal aggregation transmission module is connected to the computer data processing background using a single-mode optical fiber.

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