CN211955773U

CN211955773U - Grounding on-line monitoring device of transformer core clamping piece

Info

Publication number: CN211955773U
Application number: CN202020278672.XU
Authority: CN
Inventors: 彭程; 肖振
Original assignee: Changsha Lanhong Electric Technology Co ltd
Current assignee: Changsha Lanhong Electric Technology Co ltd
Priority date: 2020-03-09
Filing date: 2020-03-09
Publication date: 2020-11-17
Anticipated expiration: 2030-03-09

Abstract

The utility model discloses a grounding on-line monitoring device of a transformer iron core clamping piece, which belongs to a grounding monitoring manual-automatic all-in-one machine with current-limiting protection, and comprises a collecting unit, wherein the collecting unit comprises a current sensor and a collecting plate; the current sensor can collect the grounding current of an iron core or a clamping piece in the transformer in real time, and the signal output of the current sensor is connected to the collecting plate; the acquisition board comprises a single chip microcomputer, and an OLED display screen, an EEPROM chip, a key panel and an alarm indicator lamp which are respectively connected with the single chip microcomputer. The utility model discloses a device can improve parameter measurement accuracy to provide simultaneously and report to the police on the spot and inquiry function, and support diversified data to upload the mode and carry out remote monitoring.

Description

Grounding on-line monitoring device of transformer core clamping piece

Technical Field

The utility model relates to a transformer monitoring field, more specifically relates to a ground connection on-line monitoring device of transformer core folder.

Background

In a large-scale high-voltage power transformer, due to other abnormal conditions such as iron core ground faults, impurities in oil, turn-to-turn or phase faults and the like, various gases are generated in insulating oil, and the fault reasons cannot be clearly judged and the fault reasons cannot be accurately positioned and maintained by means of oil chromatographic analysis. Different overhauling methods exist for different faults, and different overhauling costs can be generated. In order to grasp the online monitoring data of the iron core/clamping piece in time before the maintenance and accurately capture the multi-point grounding latent fault of the iron core and the clamping piece, the precision of parameter detection needs to be improved, and functions such as local early warning and the like are provided so as to ensure that the latent fault is eliminated in time.

Therefore, it is highly desirable to design an online grounding monitoring device for a transformer core clamp, which can improve the precision of parameter measurement, provide local alarm and query functions, and support various data uploading methods.

SUMMERY OF THE UTILITY MODEL

Based on this, the utility model discloses a ground connection on-line monitoring device of transformer core folder, it actually belongs to a take current-limiting protection's ground connection monitoring manual-automatic all-in-one machine, the device can improve parameter measurement accuracy, and provide alarm on the spot and inquiry function simultaneously, and support diversified data upload mode and carry out remote monitoring, in addition, the device is satisfying electric power system intelligent monitor platform 61850(DL/T860) rule, can accomplish information acquisition automatically, measure, functions such as detection, the real-time and reliability of collection have been improved, the practicality improves greatly, if necessary can in time start the protection to the transformer through automatic or manual control equivalent resistance protection network.

The utility model discloses a solve above-mentioned technical problem, adopt following technical scheme:

the grounding on-line monitoring device of the transformer core clamping piece comprises an acquisition unit, wherein the acquisition unit comprises a current sensor and an acquisition board; the current sensor can collect the grounding current of an iron core or a clamping piece in the transformer in real time, and the signal output of the current sensor is connected to the collecting plate; the acquisition board comprises a single chip microcomputer, and an OLED display screen, an EEPROM chip, a key panel and an alarm indicator lamp which are respectively connected with the single chip microcomputer.

Further, the single chip microcomputer can judge whether the current collected by the current sensor exceeds an alarm threshold value and send alarm data; the EEPROM chip is used for storing current and alarm data acquired by the current sensor; the OLED display screen is used for displaying the current and the alarm data acquired by the current sensor; the key panel is used for manually setting an alarm threshold value in cooperation with the OLED display screen; the alarm indicator lamp can carry out indicator lamp flashing alarm according to the received alarm data.

Further, the acquisition board further comprises an RS485 communication module connected with the single chip microcomputer, and the RS485 communication module is used for realizing communication between the acquisition unit and the IED unit.

Furthermore, the acquisition board further comprises a 4-20mA signal output module and an alarm main contact output interface which are respectively connected with the single chip microcomputer, the 4-20mA signal output module is used for outputting 4-20mA communication signals, and the alarm main contact output interface outputs passive alarm signals according to received alarm data.

Furthermore, the grounding on-line monitoring device further comprises an IED unit and an upper computer, and the acquisition unit, the IED unit and the upper computer are sequentially in communication connection.

Further, the IED unit comprises an OLED display screen and an IEC61850 communication module.

Furthermore, the acquisition unit also comprises an equivalent resistance protection network connected with the acquisition board, and the equivalent resistance protection network can automatically input three-stage equivalent resistance step by step according to the alarm data output by the single chip microcomputer.

Furthermore, the equivalent resistance protection network is also provided with manual rotary switches S1-S3 which respectively control the three-level equivalent resistance.

The utility model discloses possess following beneficial effect:

1. the field real-time display function is improved, the function realizes the field scrolling display of the monitored current data through the OLED screen on the basis of real-time uploading, and the OLED screen is energy-saving and can display more clearly and visually, so that the current data is clear at a glance, and inspection is more convenient.

2. The parameter measurement range is widened, data are processed through the single chip microcomputer, accurate measurement from micro current to large current is guaranteed, real-time measurement from 0.5mA to 30A is achieved, the resolution ratio can reach 0.1mA, and the accuracy can reach +/-1% +/-1 mA.

3. Through setting up local alarm information record function, ground current overrun condition each time of recordable in time, including the data size and the time of transfiniting of electric current. When the grounding current of the iron core is detected to be larger than a set current value, the device can record the current data and alarm time, send out an overrun alarm and flicker an indicator light to remind a worker to pay attention to the fault state on a screen in time.

4. The data uploading mode is diversified, the selection of the data uploading mode is enriched, a user can select to connect 4-20mA signal output interface communication according to the self convenience and needs, RS485 uploading or IEC61850(DL/T860) uploading can be selected, the requirement of the user is met through the equipped upper computer monitoring software, the condition that the user does not have a self upper computer is met, the software can be used for conveniently checking and analyzing the grounding current data of the iron cores and the clamping pieces of a plurality of transformers in a station control room, and the acquisition parameters are set.

5. The current-limiting protection is carried out, and the equivalent resistance of the three-level protection in the equivalent resistance network is controlled, so that the over-limit iron core/clamp grounding current can be conveniently inhibited, and the further damage to the transformer is blocked.

Drawings

Fig. 1 is a system structure diagram of the grounding on-line monitoring device of the transformer core clamp of the present invention;

FIG. 2 is a schematic diagram of the structure of the collecting plate in the on-line monitoring device of the present invention;

description of reference numerals:

wherein, 1, a current sensor; 2. collecting a plate; 3. an equivalent resistance protection network; 21. a single chip microcomputer; a 22.4-20 mA signal output module; an EEPROM chip; an OLED display screen; an RS485 communication module; 26. a key panel; 27. an alarm indicator light; 28. alarm dry contact output interface.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention can be embodied in many different forms other than those specifically described herein, and it will be apparent to those skilled in the art that similar modifications can be made without departing from the spirit and scope of the invention, and it is therefore not to be limited to the specific embodiments disclosed below.

As shown in fig. 1-2, the utility model discloses a ground connection on-line monitoring device of transformer core folder, it actually belongs to a take ground connection monitoring manual-automatic all-in-one machine of current-limiting protection, and the device includes acquisition unit, IED unit (intelligent electronic equipment unit promptly) and host computer.

The utility model mainly aims at improving the local acquisition unit, wherein the acquisition unit comprises a current sensor 1 and an acquisition board 2; the current sensor 1 collects the current of an iron core or a clamping piece in the transformer in real time and is in communication connection with the collection plate 2; the acquisition board 2 comprises a single chip microcomputer 21, and a 4-20mA signal output module 22, an EEPROM chip 23, an OLED display screen 24, an RS485 communication module 25, a key panel 26, an alarm indicator lamp 27 and an alarm main contact output interface 28 which are connected with the single chip microcomputer 21, wherein the single chip microcomputer 21 can judge whether the current acquired by the current sensor 1 exceeds an alarm threshold value and send alarm data, the 4-20mA signal output module 22 is used for outputting a 4-20mA communication signal, the EEPROM chip 23 is used for storing the current and the alarm data acquired by the current sensor 1, and the OLED display screen 24 is used for displaying the current and the alarm data acquired by the current sensor 1 by rolling on site; the RS485 communication module 25 can realize communication between the acquisition unit and the IED unit, the key panel 26 can cooperate with the OLED display screen 24 to manually set an alarm threshold, the alarm indicator lamp 27 performs indicator lamp flashing alarm according to the received alarm data, and the alarm dry contact output interface 28 outputs a passive alarm signal according to the received alarm data.

Furthermore, the IED unit comprises an OLED display screen and an IEC61850 communication module, and the IED unit is in remote communication with the upper computer through the IEC61850 communication module.

Further, the acquisition unit further comprises an equivalent resistance protection network 3 connected with the acquisition board 2, the equivalent resistance protection network 3 receives the alarm data sent by the single chip microcomputer 21, the equivalent resistance protection network 3 comprises three-level equivalent resistances and corresponding rotary switches S1-S3, and when the grounding current of the iron core or the clamping piece is larger than a set alarm threshold value, the three-level equivalent resistances can be automatically input step by step according to the alarm data output by the acquisition board 2, so that the iron core or the clamping piece returns to the normal national standard requirement range (smaller than 100 mA). In addition, the operation and maintenance personnel can rotate the rotary switches S1-S3 in the equivalent resistance protection network 3 clockwise according to actual measurement results and requirements, so that the first-stage, second-stage and third-stage equivalent resistances can be added step by step to realize current limiting, and the switches S1-S3 can be rotated counterclockwise to cut off the resistance.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. The grounding on-line monitoring device of the transformer core clamp is characterized by comprising an acquisition unit, wherein the acquisition unit comprises a current sensor and an acquisition board; the current sensor can collect the grounding current of an iron core or a clamping piece in the transformer in real time, and the signal output of the current sensor is connected to the collecting plate; the acquisition board comprises a single chip microcomputer, and an OLED display screen, an EEPROM chip, a key panel and an alarm indicator lamp which are respectively connected with the single chip microcomputer.

2. The on-line grounding monitoring device for the transformer core clamp according to claim 1, wherein the single chip microcomputer is capable of judging whether the current collected by the current sensor exceeds an alarm threshold value and sending alarm data; the EEPROM chip is used for storing current and alarm data acquired by the current sensor; the OLED display screen is used for displaying the current and the alarm data acquired by the current sensor; the key panel is used for manually setting an alarm threshold value in cooperation with the OLED display screen; the alarm indicator lamp can carry out indicator lamp flashing alarm according to the received alarm data.

3. The on-line grounding monitoring device for the transformer core clamp according to claim 1, wherein the collecting board further comprises an RS485 communication module connected with the single chip microcomputer, and the RS485 communication module is used for realizing communication between the collecting unit and the IED unit.

4. The transformer core clamp grounding on-line monitoring device as recited in claim 2, wherein the collecting board further comprises a 4-20mA signal output module and an alarm main contact output interface respectively connected with the single chip microcomputer, the 4-20mA signal output module is used for outputting a 4-20mA communication signal, and the alarm main contact output interface outputs a passive alarm signal according to the received alarm data.

5. The on-line grounding monitoring device for the transformer core clamp according to claim 1, further comprising an IED unit and an upper computer, wherein the acquisition unit, the IED unit and the upper computer are sequentially connected in a communication manner.

6. The on-line ground monitoring device for the transformer core clamp according to claim 5, wherein the IED unit comprises an OLED display screen and an IEC61850 communication module.

7. The on-line grounding monitoring device for the transformer core clamp according to claim 2, wherein the collecting unit further comprises an equivalent resistance protection network connected with the collecting plate, and the equivalent resistance protection network can automatically switch into three levels of equivalent resistance step by step according to the alarm data output by the single chip microcomputer.

8. The on-line grounding monitoring device for transformer core clamps according to claim 7, wherein manual rotary switches S1-S3 are further provided in the equivalent resistance protection network for controlling the equivalent resistances of three stages respectively.