阅读说明：本技术 一种变压器本体储油柜油位智能在线监测系统及方法 (Intelligent online monitoring system and method for oil level of oil conservator of transformer body ) 是由 郭焕辉 吴延明 陈钰 马健 王之飞 于潇涵 孙朝勇 李云贤 张波 范云罡 柴书胜 于 2020-11-09 设计创作，主要内容包括：本发明公开了一种变压器本体储油柜油位智能在线监测系统及方法,系统包括包括压力油位变送器、信号隔离装置和无线信号收发装置,所述压力油位变送器设置在与变压器本体储油柜连接的注放油管路中,且始终低于被测最低油位的位置,用于检测变压器储油柜内变压器油量的大小,将油位压力信号转换成电信号输出至信号隔离装置；所述信号隔离装置用于将压力油位变送器输入的电信号通过半导体器件调制变换并进行隔离转换,再进行解调变换回隔离前的原信号向前传输至无线信号收发装置；所述无线信号收发装置将信号隔离装置传送的电信号发送给后台服务器。本发明能够对变压器储油柜运行状态进行监测,有效杜绝了隐患发展而引发变压器跳闸事故的发生。(The invention discloses an intelligent online oil level monitoring system and method for an oil conservator of a transformer body, wherein the system comprises a pressure oil level transmitter, a signal isolation device and a wireless signal transceiver, wherein the pressure oil level transmitter is arranged in an oil injection and discharge pipeline connected with the oil conservator of the transformer body and is always lower than the lowest oil level to be detected, and is used for detecting the oil mass of the transformer in the oil conservator of the transformer, converting an oil level pressure signal into an electric signal and outputting the electric signal to the signal isolation device; the signal isolation device is used for modulating and converting an electric signal input by the pressure oil level transmitter through a semiconductor device, carrying out isolation conversion, demodulating and converting the electric signal into an original signal before isolation, and transmitting the original signal to the wireless signal transceiver forwards; and the wireless signal receiving and transmitting device sends the electric signals transmitted by the signal isolation device to the background server. The transformer oil conservator running state monitoring system can monitor the running state of the transformer oil conservator, and effectively avoids the occurrence of transformer tripping accidents caused by the development of hidden dangers.)

1. An intelligent online oil level monitoring system of an oil conservator of a transformer body is characterized by comprising a pressure oil level transmitter, a signal isolation device and a wireless signal transceiver,

the pressure oil level transmitter is arranged in an oil injection and discharge pipeline connected with the transformer body oil conservator, is always lower than the lowest oil level to be detected, is used for detecting the oil quantity of the transformer in the transformer oil conservator, converts an oil level pressure signal into an electric signal and outputs the electric signal to the signal isolating device;

the signal isolation device is used for modulating and converting an electric signal input by the pressure oil level transmitter through a semiconductor device, carrying out isolation conversion, demodulating and converting the electric signal into an original signal before isolation, and transmitting the original signal to the wireless signal transceiver forwards;

and the wireless signal receiving and transmitting device sends the electric signals transmitted by the signal isolation device to the background server.

2. The intelligent online oil level monitoring system for the oil conservator of the transformer body as claimed in claim 1, wherein the pressure oil level transmitter comprises a pressure sensor and a signal conversion part, the pressure sensor adopts an isolation type diffusion silicon sensitive element as a measuring element, senses the pressure generated by the transformer oil under different oil levels, converts the pressure quantity into an electrical signal by using the piezoresistive effect of the pressure sensor, and indirectly reflects the change of the oil level through the change of the output electrical signal; the signal conversion part amplifies, processes and converts the electric signal generated by the sensor into 4-20mA output current after correcting the linearity and temperature response of the electric signal.

3. The intelligent online oil level monitoring system for the oil conservator of the transformer body as claimed in claim 1, wherein the signal isolation device is a one-input two-output signal isolator.

4. The intelligent online oil level monitoring system for the oil conservator of the transformer body as claimed in claim 1, wherein the signal isolation device is arranged in the local terminal box of the transformer.

5. The intelligent online oil level monitoring system for the oil conservator of the transformer body as claimed in claim 1, wherein the wireless signal transceiver comprises a wireless transmitter and a wireless receiver, the wireless transmitter transmits the electrical signal transmitted by the signal isolator, and the electrical signal is transmitted through a wireless network, received by the wireless signal receiver and stored in the database of the background server.

6. The intelligent online oil level monitoring system for the transformer body oil conservator as claimed in claim 5, wherein the wireless network comprises a 2G/3G/4G/5G wireless network.

7. The intelligent online oil level monitoring system for the transformer body oil conservator as claimed in any one of claims 1-6, further comprising an application terminal installed with monitoring software, wherein the application terminal is used for displaying, storing, analyzing, inquiring and early warning of oil level data of the transformer body oil conservator.

8. The intelligent online monitoring system for the oil level of the transformer body oil conservator as claimed in claim 7, wherein the monitoring software is used for carrying out big data analysis on real-time and historical data of the oil level of the transformer body oil conservator to diagnose the operation condition of the transformer oil conservator; if the external temperature changes and the oil level curve of the oil conservator of the transformer has regular fluctuation in a small range, judging that the oil conservator of the transformer has good running condition; if the external temperature changes and the oil level curve outlet line of the transformer oil conservator is flat, straight or unchanged for a long time, judging that the transformer oil conservator has the unsmooth breathing condition; and if the oil level curve of the transformer oil conservator drops instantly, judging that the transformer oil conservator leaks.

9. An intelligent online monitoring method for an oil level of an oil conservator of a transformer body is characterized by comprising the following steps:

the pressure oil level transmitter detects the oil quantity of a transformer in the transformer oil conservator, converts a pressure signal into an electric signal and outputs the electric signal;

the signal isolation device modulates, isolates and converts the electric signal input by the pressure oil level transmitter and demodulates the electric signal to convert the electric signal back to an original oil level signal of the transformer body oil conservator before isolation;

the wireless signal transceiver transmits and receives the oil level signal in real time through a wireless network;

the background server stores oil level detection data of the oil conservator of the transformer body;

monitoring software in the terminal is used for realizing the functions of displaying, storing, analyzing, inquiring, early warning and the like of oil level data of the oil conservator of the transformer body, and automatically drawing a real-time oil level curve and a historical curve;

the real-time and historical curve of the oil level of the oil conservator of the transformer body is retrieved; according to the real-time and historical curve change trend, big data analysis is carried out, and the running condition of the transformer oil conservator is diagnosed;

if the external temperature changes and the oil level curve of the oil conservator of the transformer has regular fluctuation in a small range, judging that the oil conservator of the transformer has good running condition;

if the external temperature changes and the oil level curve of the oil conservator of the transformer is flat, straight or unchangeable for a long time, judging that the oil conservator of the transformer has the unsmooth breathing condition;

and if the oil level curve of the transformer oil conservator drops instantly, judging that the transformer oil conservator leaks.

Technical Field

The invention relates to an intelligent online oil level monitoring system and method for an oil conservator of a transformer body, and belongs to the technical field of transformer monitoring.

Background

The oil conservator is one of the main components of the transformer, and has the function of compensating the volume expansion or contraction of the insulating oil caused by the temperature change so as to ensure the normal operation of oil-filled equipment in the oil-filled environment. And secondly, the device with the interior isolated from the air plays a role in preventing the transformer oil from absorbing moisture and oxidizing to reduce the insulating property of the transformer oil. The oil level of the oil conservator is one of important operating parameters of the power transformer and is also a key inspection project for operation and maintenance personnel, and the normal oil level is a precondition for ensuring the safe operation of the transformer.

At present, the oil level of the transformer oil conservator is widely displayed by adopting a magnetic needle type oil level meter. The floating ball is used as a sensing element, floats on the oil surface and is closely attached to the lower wall of the capsule, and moves up and down along with the rising and falling of the oil surface, and the oil level of the oil storage cabinet is indicated on a dial by a pointer through a connecting rod, a gear, a magnetic coupler and other transmission elements. And the patrol personnel can obtain the oil level information by visual observation on site.

However, the disadvantages of the current oil level monitoring methods are: the oil level monitoring system has the advantages that high and low oil level alarm signals of the oil conservator of the transformer can be transmitted only in a remote mode, the function of remote transmission of specific oil level information is not achieved, for a large number of unattended transformer substations, production, operation and maintenance departments need to conduct oil level routine inspection on each transformer hundreds of times every year, and work task load is large. And secondly, because the oil level gauge is designed and installed at a high place, and factors such as dark light in an equipment area, narrow inspection channels and the like limit the oil level, the oil level acquired by inspection personnel on site through visual observation often has certain errors. And (III) the oil level gauge is easy to have a typical fault that the oil level indication is incorrect after long-term operation, and in addition, the oil storage cabinet capsule is broken, the corrugated pipe is mechanically jammed, and the like, so that the oil level gauge indication is abnormal. When a false oil level fault that the oil level indication of the oil level indicator is inconsistent with the actual oil level of the oil storage cabinet occurs, the traditional offline monitoring mode cannot identify and eliminate the fault in time, and a good means for quickly identifying the fault is not available in the operation stage.

Disclosure of Invention

In order to solve the defects of the prior art, the invention provides an intelligent online monitoring system and method for the oil level of an oil conservator of a transformer body, which can remotely and accurately acquire the oil level information of the oil conservator of the transformer body in real time, realize the monitoring of the running state of the oil conservator of the transformer and effectively avoid the occurrence of tripping accidents of the transformer caused by the development of hidden dangers.

The technical scheme adopted for solving the technical problems is as follows:

on one hand, the intelligent online oil level monitoring system of the oil conservator of the transformer body provided by the embodiment of the invention comprises a pressure oil level transmitter, a signal isolation device and a wireless signal transceiver,

the pressure oil level transmitter is arranged in an oil injection and discharge pipeline connected with the transformer body oil conservator, is always lower than the lowest oil level to be detected, is used for detecting the oil quantity of the transformer in the transformer oil conservator, converts an oil level pressure signal into an electric signal and outputs the electric signal to the signal isolating device;

the signal isolation device is used for modulating and converting an electric signal input by the pressure oil level transmitter through a semiconductor device, carrying out isolation conversion, demodulating and converting the electric signal into an original signal before isolation, and transmitting the original signal to the wireless signal transceiver forwards;

and the wireless signal receiving and transmitting device sends the electric signals transmitted by the signal isolation device to the background server.

As a possible implementation manner of this embodiment, the pressure oil level transmitter includes a pressure sensor and a signal conversion part, where the pressure sensor uses an isolation type diffusion silicon sensitive element as a measurement element, senses the pressure generated by the transformer oil at different oil levels, converts the pressure quantity into an electrical signal by using the piezoresistive effect of the pressure sensor, and indirectly reflects the change of the oil level through the change of the output electrical signal; the signal conversion part amplifies, processes and converts the electric signal generated by the sensor into 4-20mA output current after correcting the linearity and temperature response of the electric signal.

As a possible implementation manner of this embodiment, the signal isolation device employs a one-input two-output signal isolator.

As a possible implementation manner of this embodiment, the signal isolation device is arranged in the local terminal box of the transformer.

As a possible implementation manner of this embodiment, the wireless signal transceiver includes a wireless transmitting device and a wireless receiving device, and the wireless transmitting device transmits the electrical signal transmitted by the signal isolation device, and after the electrical signal is transmitted through a wireless network, the electrical signal is received by the wireless signal receiving device and stored in a database of the background server.

As a possible implementation manner of this embodiment, the wireless network includes a 2G/3G/4G/5G wireless network.

As a possible implementation manner of this embodiment, the monitoring device further includes an application terminal installed with monitoring software, and the application terminal is used for displaying, storing, analyzing, querying and early warning the oil level data of the oil conservator of the transformer body.

As a possible implementation manner of this embodiment, the monitoring software is configured to perform big data analysis on real-time and historical data of the oil level of the oil conservator of the transformer body, and diagnose the operating condition of the oil conservator of the transformer; if the external temperature changes and the oil level curve of the oil conservator of the transformer has regular fluctuation in a small range, judging that the oil conservator of the transformer has good running condition; if the external temperature changes and the oil level curve outlet line of the transformer oil conservator is flat, straight or unchanged for a long time, judging that the transformer oil conservator has the unsmooth breathing condition; and if the oil level curve of the transformer oil conservator drops instantly, judging that the transformer oil conservator leaks.

On the other hand, the intelligent online monitoring method for the oil level of the oil conservator of the transformer body, provided by the embodiment of the invention, comprises the following steps:

the pressure oil level transmitter detects the oil quantity of a transformer in the transformer oil conservator, converts a pressure signal into an electric signal and outputs the electric signal;

the signal isolation device modulates, isolates and converts the electric signal input by the pressure oil level transmitter and demodulates the electric signal to convert the electric signal back to an original oil level signal of the transformer body oil conservator before isolation;

the wireless signal transceiver transmits and receives the oil level signal in real time through a wireless network;

the background server stores oil level detection data of the oil conservator of the transformer body;

monitoring software in the terminal is used for realizing the functions of displaying, storing, analyzing, inquiring, early warning and the like of oil level data of the oil conservator of the transformer body, and automatically drawing a real-time oil level curve and a historical curve;

the real-time and historical curve of the oil level of the oil conservator of the transformer body is retrieved; according to the real-time and historical curve change trend, big data analysis is carried out, and the running condition of the transformer oil conservator is diagnosed;

if the external temperature changes and the oil level curve of the oil conservator of the transformer has regular fluctuation in a small range, judging that the oil conservator of the transformer has good running condition;

if the external temperature changes and the oil level curve of the oil conservator of the transformer is flat, straight or unchangeable for a long time, judging that the oil conservator of the transformer has the unsmooth breathing condition;

and if the oil level curve of the transformer oil conservator drops instantly, judging that the transformer oil conservator leaks.

The technical scheme of the embodiment of the invention has the following beneficial effects:

the invention realizes accurate monitoring of real-time oil level information of the oil conservator of the transformer body, can transmit the oil level information to application terminals such as a background server, a monitor terminal and a mobile terminal in real time through a wireless network, does not need to lay a communication cable, is convenient for large data management of a regulation and control center, and fundamentally solves the problems that a common oil level gauge can only detect switching values (high and low oil levels), can only observe the oil level on the spot and has no effective remote online monitoring means for the oil level information of the transformer body.

The oil level monitoring system of the transformer body based on the differential pressure type oil level sensor is combined with the original buoyancy type oil level monitoring system, the dual configuration of the oil level monitoring system of the oil conservator of the transformer body based on two different principles is realized for the first time, the phenomenon of false oil level caused by mechanical jamming and the like in the buoyancy type oil level gauge is effectively avoided, and the more accurate oil level monitoring information of the transformer body is ensured.

According to the invention, the state monitoring of the oil conservator of the transformer body is realized through the online oil level monitoring for the first time, the change trend of the oil level of the transformer is tracked through the remote real-time acquisition of the oil level information, the big data analysis is carried out by combining other parameters such as environment, load and the like, the effective prejudgment of the running state of the oil conservator of the transformer body is indirectly realized, the equipment state maintenance is carried out in a targeted manner, and the occurrence of transformer tripping accidents caused by the expansion of hidden dangers is avoided.

Description of the drawings:

FIG. 1 is a schematic block diagram of an intelligent online monitoring system for oil level in a transformer body conservator according to an exemplary embodiment;

FIG. 2 is a schematic diagram of an application scenario of the present invention;

FIG. 3 is a schematic diagram of a signal isolation device according to the present invention;

fig. 4 is a flowchart illustrating an intelligent online monitoring method for the oil level of a transformer body conservator according to an exemplary embodiment.

Detailed Description

The invention is further illustrated by the following examples in conjunction with the accompanying drawings:

in order to clearly explain the technical features of the present invention, the following detailed description of the present invention is provided with reference to the accompanying drawings. The following disclosure provides many different embodiments, or examples, for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. It should be noted that the components illustrated in the figures are not necessarily drawn to scale. Descriptions of well-known components and processing techniques and procedures are omitted so as to not unnecessarily limit the invention.

As shown in fig. 1 to 3, an intelligent online oil level monitoring system for a transformer body oil conservator provided by the embodiment of the invention comprises a pressure oil level transmitter, a signal isolation device and a wireless signal transceiver,

the pressure oil level transmitter is arranged in an oil injection and discharge pipeline connected with the transformer body oil conservator, is always lower than the lowest oil level to be detected, is used for detecting the oil quantity of the transformer in the transformer oil conservator, converts an oil level pressure signal into an electric signal and outputs the electric signal to the signal isolating device;

the signal isolation device is used for modulating and converting an electric signal input by the pressure oil level transmitter through a semiconductor device, carrying out isolation conversion, demodulating and converting the electric signal into an original signal before isolation, and transmitting the original signal to the wireless signal transceiver forwards;

and the wireless signal receiving and transmitting device sends the electric signals transmitted by the signal isolation device to the background server.

As a possible implementation manner of this embodiment, the pressure oil level transmitter includes a pressure sensor and a signal conversion part, where the pressure sensor uses an isolation type diffusion silicon sensitive element as a measurement element, senses the pressure generated by the transformer oil at different oil levels, converts the pressure quantity into an electrical signal by using the piezoresistive effect of the pressure sensor, and indirectly reflects the change of the oil level through the change of the output electrical signal; the signal conversion part amplifies, processes and converts the electric signal generated by the sensor into 4-20mA output current after correcting the linearity and temperature response of the electric signal.

As a possible implementation manner of this embodiment, the signal isolation device employs a one-input two-output signal isolator. The signal isolator has a photoelectric isolation transmitting and outputting function, improves the electrical isolation performance among input, output and power supplies, can well protect a lower-level control loop, and is convenient for the maintenance of a higher-level sensor loop; secondly, the device has a one-to-many conversion isolation output function of input signals, and expands the independent use range; and thirdly, the oil level sensor has an on-site digital display function, and converts a 4-20mA low-current analog quantity signal output by the sensor, so that the oil level value can be conveniently read on site.

As a possible implementation manner of this embodiment, the signal isolation device is arranged in the local terminal box of the transformer.

As a possible implementation manner of this embodiment, the wireless signal transceiver includes a wireless transmitting device and a wireless receiving device, and the wireless transmitting device transmits the electrical signal transmitted by the signal isolation device, and after the electrical signal is transmitted through a wireless network, the electrical signal is received by the wireless signal receiving device and stored in a database of the background server.

As a possible implementation manner of this embodiment, the wireless network includes a 2G/3G/4G/5G wireless network. The wireless transmitting device transmits long-distance data through a 2G/3G/4G/5G wireless network by using a GPRS/CDMA technology; the wireless receiving device receives data and stores the data in the server and a corresponding database, so that a remote terminal such as a mobile phone, a tablet computer or a station background monitor can read the data in real time.

As a possible implementation manner of this embodiment, the monitoring device further includes an application terminal installed with monitoring software, and the application terminal is used for displaying, storing, analyzing, querying and early warning the oil level data of the oil conservator of the transformer body. The application terminal can realize the functions of displaying, storing, analyzing, inquiring, early warning and the like of the oil level data of the oil conservator of the transformer body, can automatically draw a real-time oil level curve and a historical curve, monitors the state and the trend of the oil level in real time, and is convenient for a regulation and control center to carry out big data management.

As a possible implementation manner of this embodiment, the monitoring software is configured to perform big data analysis on real-time and historical data of the oil level of the oil conservator of the transformer body, and diagnose the operating condition of the oil conservator of the transformer; if the external temperature changes and the oil level curve outlet line of the transformer oil conservator is flat, straight or unchanged for a long time, judging that the transformer oil conservator has the unsmooth breathing condition; and if the oil level curve of the transformer oil conservator drops instantly, judging that the transformer oil conservator leaks.

As shown in fig. 4, the method for intelligently monitoring the oil level of the oil conservator of the transformer body provided by the embodiment of the invention comprises the following steps:

the pressure oil level transmitter detects the oil quantity of a transformer in the transformer oil conservator, converts a pressure signal into an electric signal and outputs the electric signal;

the signal isolation device modulates, isolates and converts the electric signal input by the pressure oil level transmitter and demodulates the electric signal to convert the electric signal back to an original oil level signal of the transformer body oil conservator before isolation;

the wireless signal transceiver transmits and receives the oil level signal in real time through a wireless network;

the background server stores oil level detection data of the oil conservator of the transformer body;

monitoring software in the terminal is used for realizing the functions of displaying, storing, analyzing, inquiring, early warning and the like of oil level data of the oil conservator of the transformer body, and automatically drawing a real-time oil level curve and a historical curve;

the real-time and historical curve of the oil level of the oil conservator of the transformer body is retrieved; according to the real-time and historical curve change trend, big data analysis is carried out, and the running condition of the transformer oil conservator is diagnosed;

if the external temperature changes and the oil level curve of the oil conservator of the transformer has regular fluctuation in a small range, judging that the oil conservator of the transformer has good running condition;

if the external temperature changes and the oil level curve of the oil conservator of the transformer is flat, straight or unchangeable for a long time, judging that the oil conservator of the transformer has the unsmooth breathing condition;

and if the oil level curve of the transformer oil conservator drops instantly, judging that the transformer oil conservator leaks.

The foregoing is only a preferred embodiment of the present invention, and it will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and these modifications and improvements are also considered to be within the scope of the present invention.