CN205246806U - Long -range cable on -line measuring system - Google Patents

Abstract

The utility model provides a remote cable online detection system, which includes a remote processing terminal and an on-site detection terminal; the remote processing terminal includes a remote processor, a remote wireless communication module, a display, an alarm and a memory; the on-site detection terminal includes a low-pass filter circuit , amplifier, A/D collector, microprocessor and on-site wireless communication module; the remote processor is connected to the remote wireless communication module, display, alarm and memory respectively; the low-pass filter circuit is used to access the cable under test, and The filtered direct current is sent to the amplifier for amplification processing; the amplifier, A/D collector and microprocessor are connected in sequence; the communication terminal of the microprocessor is connected with the field wireless communication module; the field wireless communication module is wirelessly connected with the remote wireless communication module. The detection system can realize the remote wireless communication between the remote processing terminal and each on-site detection terminal, which saves detection time and improves the detection efficiency of water trees.

Description

A remote cable online detection system

technical field

The utility model relates to a cable detection system, in particular to a system for remote detection of cables.

Background technique

The insulation of XLPE power cables can deteriorate due to chemical, thermal and electrical factors. The water tree phenomenon is considered to be one of the important causes of aging. Therefore, some researchers believe that the main work of XLPE cable insulation aging diagnosis is how to detect water trees before breakdown. It has been found that when the XLPE cable insulation in service contains water treeing, a small DC component exists between the conductor core and the copper shield and this DC component is characteristic of cracking caused by water treeing in the insulation. By measuring the DC component, it is possible to diagnose insulation aging as a result of water treeing. The main principle of the DC component method is to use the rectification effect when there are water trees in the cable. In the negative half cycle of the applied voltage, the water tree branch injects more negative charges from the tip into the insulation, while in the positive half cycle the injected positive charges are less, so that only a part of the charge is neutralized. Under the power frequency voltage of the cable operation, the negative charge at the front of the water branch gradually drifts to the other side, and the DC component appears just like the rectification effect, but the value is very small, only a few to tens of nanoamperes. The development of water trees often indicates an increase in leakage current, and such a degradation process leads to a decrease in AC breakdown voltage.

Contents of the invention

The main purpose of the utility model is to provide a system capable of realizing remote on-line detection of cables, which is convenient for on-line detection of cables and effectively avoids the phenomenon of water trees at the outlet of cables from affecting power supply.

In order to solve the above technical problems, the utility model provides a remote cable online detection system, including a remote processing terminal and at least one on-site detection terminal; the remote processing terminal includes a remote processor, a remote wireless communication module, a display, an alarm and a memory; The on-site detection terminal includes a low-pass filter circuit, amplifier, A/D collector, microprocessor and on-site wireless communication module; the communication end of the remote processor is connected to the remote wireless communication module; the display signal end of the remote processor is connected to the display; The signal output terminal of the remote processor is connected to the alarm; the signal input and output terminals of the remote processor are connected to the memory; the low-pass filter circuit is used to connect the tested cable, and the filtered direct current is sent to the amplifier for amplification; the amplifier The output end of the A/D collector is connected with the input end of the A/D collector; the output end of the A/D collector is connected with the signal input end of the microprocessor; the communication end of the microprocessor is connected with the field wireless communication module; the field wireless communication module is connected with the The remote wireless communication module connects wirelessly.

The remote wireless communication module and the real-time remote wireless communication of the on-site wireless communication module are used to realize the remote wireless communication between the remote processing terminal and each on-site detection terminal, without the need for inspection of each detection cable, which saves detection time and improves detection efficiency. ;The low-pass filter circuit can effectively filter out the AC component in the cable, and detect the DC component separately for water tree detection; the amplifier can amplify the DC component detected by the sub-detection, so that the weak DC component meets the requirements of A/D Acquisition requirements of the collector; the monitor can display the detection status of each on-site detection terminal in real time, and the alarm will send out an alarm when the water tree phenomenon is detected.

As a further improvement of the utility model, the remote processing terminal further includes a GSM short message module; another signal output end of the remote processor is connected to the GSM short message module. The GSM short message module can notify the monitoring personnel by short message in time when the water tree phenomenon is detected, which is convenient for timely processing.

As a further improvement of the utility model, the low-pass filter circuit is composed of a π-type filter, an RC filter and a grounding protection resistor R2 connected in sequence.

As a further improvement of the utility model, the π-type filter is composed of capacitor C1, capacitor C2 and inductor L1; the RC filter is composed of resistor R1 and capacitor C3; the grounding protection resistor R2 is connected in parallel with capacitor C3.

The beneficial effects of the utility model are as follows: (1) The remote wireless communication module and the real-time remote wireless communication of the on-site wireless communication module are adopted to realize the remote wireless communication between the remote processing terminal and each on-site detection terminal without the need to inspect each detection cable detection, which saves detection time and improves detection efficiency; (2) The low-pass filter circuit can effectively filter out the AC components in the cable, and sub-detect the DC components for water tree detection; (3) The use of amplifiers can Amplify the DC components so that the weak DC components meet the acquisition requirements of the A/D collector; (4) The monitor can display the detection status of each on-site detection terminal in real time, and the alarm will be activated when the water tree phenomenon is detected. Alert.

Description of drawings

Fig. 1 is the structural representation of the utility model.

detailed description

As shown in Figure 1, the remote cable online detection system of the present invention includes: a remote processing terminal and at least one on-site detection terminal; the remote processing terminal is used to be installed in the control center; the on-site detection terminal is used to be installed at each cable to be tested.

Among them, the remote processing terminal includes a remote processor, a remote wireless communication module, a display, an alarm, and a memory; the on-site detection terminal includes a low-pass filter circuit, an amplifier, an A/D collector, a microprocessor, and an on-site wireless communication module; The communication terminal of the remote processor is connected with the remote wireless communication module; the display signal terminal of the remote processor is connected with the display; the signal output terminal of the remote processor is connected with the alarm; the signal input and output terminals of the remote processor are connected with the memory; the low-pass filter circuit It is used to connect the cable under test, and send the filtered direct current to the amplifier for amplification; the output of the amplifier is connected to the input of the A/D collector; the output of the A/D collector is connected to the signal of the microprocessor The input end is connected; the communication end of the microprocessor is connected with the field wireless communication module; the field wireless communication module is wirelessly connected with the remote wireless communication module; the remote processing terminal also includes a GSM short message module; the other signal output end of the remote processor is connected with the GSM The SMS module is connected; the low-pass filter circuit is composed of a π-type filter, an RC filter and a grounding protection resistor R2 connected in sequence; the π-type filter is composed of a capacitor C1, a capacitor C2 and an inductor L1; the RC filter is composed of a resistor R1 and a capacitor C3 constitutes; the grounding protection resistor R2 is connected in parallel with the capacitor C3.

When the remote cable on-line detection system of the utility model is working, firstly, the AC component in the cable is filtered out through a low-pass filter circuit, and the DC component is detected separately; The DC component meets the acquisition requirements of the A/D collector; then the microprocessor processes the acquisition signal of the A/D collector and judges whether it exceeds the set threshold; then the microprocessor passes the processing results and judgment results through The on-site wireless communication module wirelessly sends to the remote wireless communication module; the remote processor stores all the received information in the memory, and then displays the processing results and judgment results through the display, and activates the alarm to alarm when receiving information exceeding the threshold. At the same time, the monitoring personnel are notified through the GSM SMS module for timely processing.

Claims (4)

1. a remote cable on-line detecting system, is characterized in that: comprise teleprocessing terminal and at least one Site Detection terminal; Teleprocessing terminal comprises teleprocessing unit, remote wireless communication module, display, alarm and memory; Site Detection terminal comprises low-pass filter circuit, amplifier, A/D collector, microprocessor and on-site wireless communication module; The communication ends of teleprocessing unit is connected with remote wireless communication module; The display end of teleprocessing unit is connected with display; The signal output part of teleprocessing unit is connected with alarm; The signal input output end of teleprocessing unit is connected with memory; Low-pass filter circuit is used for accessing tested cable, and filtered direct current is sent into amplifier and amplify processing; The output of amplifier is connected with the input of A/D collector; The output of A/D collector is connected with the signal input part of microprocessor; The communication ends of microprocessor is connected with on-site wireless communication module; On-site wireless communication module and remote wireless communication module wireless connections.

2. remote cable on-line detecting system according to claim 1, is characterized in that: teleprocessing terminal also comprises a GSM SMS module; Another signal output part of teleprocessing unit is connected with GSM SMS module.

3. remote cable on-line detecting system according to claim 1 and 2, is characterized in that: low-pass filter circuit is made up of the pi type filter being connected successively, RC wave filter and ground protection resistance R 2.

4. remote cable on-line detecting system according to claim 3, is characterized in that: pi type filter is made up of capacitor C 1, capacitor C 2 and inductance L 1; RC wave filter is made up of resistance R 1 and capacitor C 3; Ground protection resistance R 2 is in parallel with capacitor C 3.