CN112098763A - Live detection and online monitoring method for transformer substation lightning arrester - Google Patents

Abstract

The invention belongs to the technical field of electric power. The method for detecting the live line of the lightning arrester of the transformer substation and monitoring the lightning arrester on line is characterized by comprising the following steps of: 1) preparing a novel lightning arrester live monitoring and on-line monitoring system, wherein the novel lightning arrester live monitoring and on-line monitoring system comprises an on-line monitor and a live monitoring device; the on-line monitor comprises a precision reference source and a signal acquisition system; the live monitoring device comprises a station control monitoring unit and a communication module; 2) the current on the grounding lead of each arrester in the A-phase arrester group, the B-phase arrester group and the C-phase arrester group is synchronously measured through the measuring module to obtain A, B, C three-phase leakage current, the amplitude, the included angle, the resistive current and the power data of the three-phase leakage current are calculated through high-order FFT calculation by utilizing the locking relation of the phase angle difference of the three-phase leakage current, and then whether the working state of the arrester is good or not is determined through comparison with historical data. The method improves the reliability, accuracy and convenience of live detection.

Description

Method for live detection and online monitoring of arrester in substation

technical field

The invention belongs to the field of electric power technology, and particularly relates to a method for live detection and online monitoring of a lightning arrester in a substation.

Background technique

At present, explosion accidents of arresters in operation of substations occur frequently due to valve plate aging and electrical performance deterioration. The traditional detection, tracking and monitoring methods have many drawbacks, and cannot effectively and timely detect the internal defects of arresters, which brings a lot to the safe operation of the power grid. Serious threat.

The live test of the arrester is mainly based on two factors, the system voltage and the leakage current, namely the UI method. The practical problem brought by the UI method is that the resistive current value is an estimated value, which is not accurate in practice, and there is a risk of short circuit in obtaining the voltage signal. The live measurement method of the arrester using the UI method is complicated to measure the wiring, which is not conducive to the accurate, fast and efficient live test of the arrester.

To judge the status of the arrester, the first method of power outage maintenance was adopted. Because the on-site test is mostly to apply a DC voltage to test the leakage current, the actual operating conditions of the equipment cannot be restored, and hidden faults cannot be found, and the power outage maintenance is not conducive to the stable operation of the system. Material and financial investment is large.

In order to solve the problems of poor anti-interference ability and low measurement accuracy of arrester live detection and on-line monitoring instruments, it is urgent to develop a method for live detection and on-line monitoring of surge arresters in substations and a new live monitoring and on-line monitoring system for surge arresters to solve the current problems of arrester monitoring. .

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a method for live detection and on-line monitoring of a lightning arrester in a substation, which improves the reliability, accuracy and convenience of live detection.

In order to achieve the above purpose, the technical scheme adopted by the present invention is: a method for live detection and online monitoring of a lightning arrester in a substation, which is characterized by comprising the following steps:

1) Prepare a new type of arrester live monitoring and online monitoring system, which includes an online monitor 19 and a live monitoring device 20;

The online monitor 19 includes a precision reference source 2 and a signal acquisition system 3; the signal acquisition system 3 includes an A-phase measurement module 14, a B-phase measurement module 16, a C-phase measurement module 18, a signal acquisition module 5 and three signal conditioning modules 4;

A-phase measurement module 14 , B-phase measurement module 16 , C-phase measurement module 18 , A-phase measurement module 14 , The B-phase measurement module 16 and the C-phase measurement module 18 are respectively connected with the input terminals of the corresponding three signal conditioning modules 4 by signal lines, and the output terminals of all the signal conditioning modules 4 are connected with the input terminals of the signal acquisition module 5. The output end of the signal acquisition module 7 is connected with the input end of the station control monitoring unit 6 of the live monitoring device 20; the high-precision reference source 2 is connected with the input end of the signal acquisition module 5;

The live monitoring device 20 includes a station control monitoring unit 6 and a communication module 7; the output end of the station control monitoring unit 6 is connected with the input end of the communication module 7, and the communication module 7 transmits data to the host computer 9 or 7 through a wired or wireless data channel. \ and mobile monitoring terminal 8;

2) Simultaneously measure the current on the grounding lead of each arrester in the A-phase arrester group 13, B-phase arrester group 15, and C-phase arrester group 17 through the measurement module, and obtain the leakage current of the three-phase A, B, and C phases. The locking relationship of the phase angle difference of the current, through the high-order FFT calculation, calculate the amplitude, angle, resistive current and power data of the three-phase leakage current, and then compare with the historical data to determine whether the arrester is in working state. good.

The measurement module is a current sensor.

The station control monitoring unit is a central processing unit.

The beneficial effects of the present invention are: the method improves the reliability, accuracy and convenience of electrification detection.

Description of drawings

Fig. 1 is the structure diagram of the new-type arrester live monitoring and on-line monitoring system of the present invention.

FIG. 2 is a schematic structural diagram of the online monitor and the live monitoring device of the present invention.

In the figure: 1-ABC three-phase arrester leakage current signal, 2-precision reference source, 3-signal acquisition system, 4-signal conditioning module, 5-signal acquisition module, 6-station control monitoring unit CPU, 7-communication module, 8-Mobile monitoring terminal, 9-Host computer, 10-A-phase line, 11-B-phase line, 12-C-phase line, 13-A-phase arrester group, 14-A-phase measurement module (on-line monitor), 15 -B-phase arrester group, 16-B-phase measurement module (on-line monitor), 17-C-phase arrester group, 18-C-phase measurement module (on-line monitor), 19-On-line monitor, 20-Live monitoring device .

Detailed ways

In order to better understand the present invention, the technical solutions of the present invention will be further described below with reference to the embodiments and accompanying drawings.

The method for live detection and on-line monitoring of a lightning arrester in a substation includes the following steps:

1) Prepare a new type of arrester live monitoring and on-line monitoring system, as shown in Figures 1 and 2, the new type of arrester live monitoring and on-line monitoring system includes an on-line monitor 19 and a live monitoring device 20;

The online monitor 19 includes a precision reference source 2 and a signal acquisition system 3; the signal acquisition system 3 includes a signal acquisition module 5, three signal conditioning modules 4, an A-phase measurement module 14, a B-phase measurement module 16, and a C-phase measurement module 18;

A-phase arrester group (zinc oxide arrester group) 13 , B-phase arrester group 15 , C-phase arrester group 17 are installed with corresponding A-phase measurement modules 14 , B-phase measurement modules 16 , C-phase measurement modules 18 { Such as: current measurement sensor, or current sensor; the number of measurement modules is 3, corresponding to the grounding leads of the A-phase arrester group (zinc oxide arrester group) 13, the B-phase arrester group 15, and the C-phase arrester group 17}, A The phase measurement module 14, the B-phase measurement module 16, and the C-phase measurement module 18 are respectively connected with the input ends of the corresponding three signal conditioning modules 4 by signal lines (data lines) (the signals of the measurement modules are conditioned; The number of modules 4 corresponds to the number of measurement modules), and the output terminals of all signal conditioning modules 4 are connected to the input terminals of signal acquisition module 5 {signal acquisition module 5 collects the signals of all measurement modules, and then sends them to the station The control monitoring unit CPU (central processing unit CPU) 6 performs analysis and processing}, and the output end of the signal acquisition module 7 is connected with the input end of the station control monitoring unit CPU (central processing unit CPU) 6 of the live monitoring device 20; The source 2 is connected to the input end of the signal acquisition module 5 (the high-precision reference source is used as the reference);

The live monitoring device 20 includes a station control monitoring unit CPU (central processing unit CPU) 6 and a communication module 7; the output end of the station control monitoring unit CPU (central processing unit CPU) 6 is connected with the input end of the communication module 7, and the communication module 7 Through wired or wireless data channels, transmit data to the host computer (surge arrester status evaluation system) 9 or \ and mobile monitoring terminal (mobile phone, handheld terminal) 8; that is: transmit data to the host computer 9 or mobile monitoring terminal 8, or transmit data to the host computer 9 and the mobile monitoring terminal 8;

2) Simultaneously measure the current on the grounding lead of each arrester in the A-phase arrester group (zinc oxide arrester group) 13, B-phase arrester group 15, and C-phase arrester group 17 through the measurement module, and obtain the leakage of the three-phase A, B, and C phases. Current (ABC three-phase arrester leakage current signal 1), using the locking relationship of the phase angle difference of the three-phase leakage current, through high-order FFT calculation, calculate the amplitude, angle, resistive current and power of the three-phase leakage current Data, and then compare with historical data to determine whether the arrester is in good working condition.

The new type of arrester live monitoring and online monitoring system has simple structure, easy wiring, convenient and maintenance, convenient use, and friendly human-computer interaction, so as to conduct characteristic test of zinc oxide arrester and evaluate the performance of zinc oxide arrester.

The new arrester live monitoring and online monitoring system itself has a communication module. After data encryption, the data is transmitted to the local machine (surge arrester status evaluation system) 9 or mobile monitoring terminal (mobile phone, handheld terminal) 8 through wired or wireless data channels. Analysis application software.

The application software can import historical data, record and save the test data, and upload it to the back-end server dedicated to the State Grid Corporation, which is convenient for later review and analysis. The new arrester live tester supports data upload, download and storage, obtains the historical data of the arrester, analyzes the working status of the arrester, and produces test reports. A good realization of man-machine interconnection, redefines the intelligence of the new arrester live tester.

By using the new method of the present invention, the monitoring effect of the operation state of the arrester can be effectively improved, the operation risk of the defective arrester can be eliminated, and the reliability of the operation of the power grid can be effectively improved; The test maintenance cost brings huge economic benefits.

Claims (3)

1. The method for live detection and on-line monitoring of lightning arrester in substation is characterized in that comprising the steps: 1) Prepare a new type of arrester live monitoring and on-line monitoring system, which includes an on-line monitor (19) and a live monitoring device (20); The online monitor (19) includes a precision reference source (2) and a signal acquisition system (3); the signal acquisition system (3) includes an A-phase measurement module (14), a B-phase measurement module (16), and a C-phase measurement module (18) ), a signal acquisition module (5) and three signal conditioning modules (4); A-phase measurement module (14), B-phase measurement module (16), C-phase measurement module (14), B-phase measurement module (16), C-phase measurement module (14), B-phase measurement module (16), C-phase arrester group (17) The measurement module (18), the A-phase measurement module (14), the B-phase measurement module (16), and the C-phase measurement module (18) are respectively connected with the input ends of the corresponding three signal conditioning modules (4) by signal lines, The output terminals of all signal conditioning modules (4) are connected to the input terminals of the signal acquisition module (5), and the output terminals of the signal acquisition module (7) are connected to the input terminal of the station control monitoring unit (6) of the live monitoring device (20). The high-precision reference source (2) is connected with the input end of the signal acquisition module (5); The live monitoring device (20) comprises a station control monitoring unit (6) and a communication module (7); the output end of the station control monitoring unit (6) is connected with the input end of the communication module (7), and the communication module (7) is wired through Or wireless data channel, transmit data to upper computer (9) or \ and mobile monitoring terminal (8); 2) Simultaneously measure the current on the grounding lead of each arrester in the A-phase arrester group (13), B-phase arrester group (15), and C-phase arrester group (17) through the measurement module, and obtain the leakage of the three-phase A, B, and C phases. Current, using the locking relationship of the phase angle difference of the three-phase leakage current, through high-order FFT calculation, calculate the amplitude, angle, resistive current and power data of the three-phase leakage current, and then compare with the historical data, Determine whether the arrester is in good working condition. 2 . The method for live detection and online monitoring of a lightning arrester in a substation according to claim 1 , wherein the measurement module is a current sensor. 3 . 3 . The method for live detection and on-line monitoring of a lightning arrester in a substation according to claim 1 , wherein the station control monitoring unit is a central processing unit. 4 .

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