CN107328518A - GIS device SF6 on-line monitoring systems and its method of work - Google Patents

Abstract

A GIS equipment SF6 online monitoring system and its working method relate to a monitoring field. At present, the GIS equipment SF6 online monitoring system often has data errors and inaccuracies. The invention includes: a manual transcription data input module; a pressure acquisition module; a temperature acquisition module; an atmospheric pressure monitoring module; a data analysis module; It is used to analyze and judge the data processed by the data preprocessing module; the over-limit alarm module, when the pressure monitoring and analysis module determines that the over-limit is exceeded, it will issue an over-limit alarm; and the data storage module. This technical solution compensates the SF6 pressure for temperature and atmospheric pressure; combined with the manual transcription data, the online monitoring data is corrected to effectively improve the accuracy of the data.

Description

GIS Equipment SF6 Online Monitoring System and Its Working Method

technical field

The invention relates to a monitoring field, in particular to a GIS equipment SF6 online monitoring system and a working method thereof.

Background technique

The main online monitoring equipment in the substation includes transformer (high resistance) oil chromatography, iron core, clamp grounding current online monitoring, transformer, GIS equipment partial release online monitoring, circuit breaker and GIS equipment SF ₆ pressure online monitoring, etc. ^[1] . With the popularization of GIS equipment application, more and more SF ₆ pressure online monitoring functions are applied. Especially in UHV substations, due to its large capacity, long distance, and cross-regional power transmission, a large number of high-voltage GIS electrical equipment is used, and its SF6 gas pressure and performance will directly affect the safety of UHV electrical equipment.

At present, SF6 online monitoring devices in substations generally upload the collected data to the monitoring system, and the monitoring system uses the collected data to display and compare with the set alarm value. When the pressure is lower than the alarm value, it will alarm, that is, only It can realize SF ₆ pressure display and over-limit alarm. This method does not fully process and mine the collected data, so that some relatively hidden defects or slow development of defects cannot be discovered in time. For example, the pressure of SF ₆ gas in a gas chamber of an UHV substation GIS has been on a downward trend, but because the rate of decline is very slow, and after several months of leakage, the pressure value is still greater than the rated pressure, so the monitoring system has not Call the police. The above problems affect the safety of high-voltage electrical equipment and urgently need to be improved.

The pressure data collected by the online monitoring sensor probe is relative pressure, without considering the change of atmospheric pressure. Some sensors do not consider the temperature factor, and the collected data will fluctuate greatly with the change of temperature. In addition, due to problems such as probes in the online monitoring system, data errors often occur, resulting in inaccurate data.

Contents of the invention

The technical problem to be solved and the technical task proposed by the present invention are to perfect and improve the existing technical solutions, to provide a GIS equipment SF6 online monitoring system and its working method, so as to achieve the purpose of improving the safety of high-voltage electrical equipment. For this reason, the present invention takes the following technical solutions.

GIS equipment SF6 online monitoring system is characterized in that it includes:

Manual transcription data input module: used for the input of manual transcription data;

The pressure acquisition module is used to acquire the pressure of each gas chamber on the substation GIS equipment;

A temperature acquisition module, configured to acquire the temperature in each or more air chambers;

Atmospheric pressure monitoring module for collecting atmospheric pressure;

The data analysis module is used to perform data analysis on the information obtained by the pressure acquisition module, temperature acquisition module and atmospheric pressure monitoring module, and obtain the corresponding air chamber pressure, temperature and atmospheric pressure;

The data preprocessing module obtains the absolute pressure according to the pressure of the gas chamber and the atmospheric pressure, and compensates the absolute pressure according to the corresponding temperature in the gas chamber; combined with the manual transcription data, the online monitoring data is corrected;

The pressure monitoring and analysis module is used to analyze and judge the data processed by the data preprocessing module; it includes a pressure over-limit judgment sub-module for pressure over-limit judgment, and an adjacent air chamber pressure comparison for adjacent air chamber pressures. Comparison sub-module, pressure comparison sub-module at different times for pressure comparison at different times, initial pressure comparison sub-module for comparison with the initial pressure value, pressure mutation judgment sub-module for pressure mutation judgment, adjacent air chamber pressure comparison It is used to reflect the leakage between adjacent gas chambers and its leakage degree and speed; the comparison with the initial pressure value is used to automatically report the gas chamber where SF6 leakage occurs, and it compares the online monitoring pressure data with the stored corresponding gas chamber pressure The initial value is calculated as a difference, and when the difference exceeds the threshold value, it is automatically reported; the pressure comparison and pressure mutation judgment at different times are used to reflect the pressure of the same gas chamber at different times, and calculate the SF6 leakage rate of each gas chamber. It is calculated by the second-order algorithm; the pressure comparison of adjacent air chambers is calculated by the second-order algorithm;

The over-limit alarm module, when the pressure monitoring and analysis module judges over-limit, it will issue an over-limit alarm;

The data storage module is a data storage module for storing data.

This technical solution monitors the air pressure of each air chamber, and adds a pressure comparison module for adjacent air chambers to compare the pressures of two adjacent air chambers. When the pressure difference between the two air chambers exceeds the limit, an alarm can be issued to detect a single air chamber in time. Air leakage can improve the safety and reliability of GIS equipment in substations. Various methods are used for comparison and analysis, and multi-angle monitoring can detect abnormalities in time, thereby ensuring the stability of its working pressure.

This technical solution compensates the SF6 pressure for temperature and atmospheric pressure; combined with manual transcription data, the online monitoring data is corrected. Effectively improve the accuracy of data.

As a further improvement and supplement to the above technical solutions, the present invention also includes the following additional technical features.

Further, when calculating the absolute pressure, the data preprocessing module adopts the formula: P=0.098×(0.58×10 ⁻³ γT(1+B)−γ ² A);

A=0.764×10 ^-3 (1-0.727×10 ^-3 γ);

B=2.51×10 ^-3 γ (1-0.846×10 ^-3 γ);

Among them: P: absolute pressure value, unit: Mpa;

γ: gas density, unit: kg/m ³ ;

T: absolute temperature, unit K;

And the temperature coefficient of gas pressure is obtained from the above formula:

k=0.098×(0.58×10 ^-3 γ(1+B)), unit: Mpa/°C.

The gas density is calculated according to the gas density at the initial installation, or the pressure and temperature by the above formula; during operation, the pressure temperature coefficient k value is calculated by the formula, combined with the actual temperature value, the gas pressure is uniformly converted to a temperature of 20°C The pressure, and then carry out the comparative analysis of the follow-up pressure to remove the temperature factor and make the calculation more accurate.

Further, the online monitoring system also includes a display module. After the analysis is completed, the display module is used to generate reports and curves to analyze the data and predict the SF6 leakage trend.

Further, the pressure acquisition module includes a plurality of SF6 pressure monitors, and each air chamber of the GIS equipment is equipped with an SF6 pressure monitor to collect the pressure value of each air chamber.

Further, when the substation GIS equipment is 1000KV GIS equipment, each 1000kV GIS circuit breaker unit is equipped with a junction box, which is used to connect all SF6 pressure monitors of this circuit breaker unit.

Further, the junction box is set in an SF6 online monitoring system cabinet, and the SF6 online monitoring system cabinet is connected to 1000kV GIS status monitoring information, and the SF6 online monitoring system cabinet is provided with a device for uploading the 1000kV GIS status monitoring information to The communication module of the integrated monitoring system.

Further, when the substation GIS equipment is 500kV GIS equipment, each 500kV GIS circuit breaker unit is equipped with one SF6 monitoring sub-IED, and at the same time configures one 500kV SF6 online monitoring main IED, 500kV SF6 online monitoring main IED and SF6 monitoring sub-IED The connection is used to aggregate status monitoring information and upload it to the integrated monitoring system.

Further, the GIS equipment SF6 online monitoring system is independently networked in Zone II, and the information data is connected to the comprehensive application server using the DL/T860 (IEC61850) protocol. The communication gateway in Zone II uses the DL/T634.5104 protocol to communicate with dispatchers at all levels. Transmission of online monitoring information.

Another object of the present invention is to provide a kind of GIS equipment SF The on-line monitoring method of on-line monitoring system, it comprises the following steps:

1) Manually transcribing the data step, manually transcribing the SF6 density table data at regular intervals, and importing the manually transcribed SF6 density table data into the system through the manual transcription data input module;

2) In the pressure collection step, the SF6 pressure monitor collects the pressure of each gas chamber on the substation GIS equipment;

3) The temperature collection step is to collect the temperature of each air chamber or several air chambers therein;

4) The atmospheric pressure monitoring module collects real-time atmospheric pressure;

5) The data analysis step is to perform data analysis on the information obtained by the pressure acquisition module, the temperature acquisition module and the atmospheric pressure monitoring module, and obtain the corresponding air chamber pressure, temperature and atmospheric pressure;

6) Data preprocessing step, obtain the absolute pressure according to the air chamber pressure and atmospheric pressure, and compensate the absolute pressure according to the corresponding temperature in the air chamber; calculate the difference between the manual transcription data and the online monitoring data, when the manual transcription data and the online monitoring data When the difference between the monitoring data is greater than the threshold, confirm whether the online monitoring probe is faulty, and replace the online monitoring data with manual transcription data, and correct the online monitoring data;

7) The pressure monitoring and analysis step is to analyze and judge the data processed by the data preprocessing module; including the judgment of pressure exceeding the limit, the comparison of the pressure of adjacent air chambers, the comparison of pressure at different times, the comparison with the initial pressure value, the judgment of sudden pressure changes, and the judgment of adjacent air chambers. The comparison of gas chamber pressure is used to reflect the leakage between adjacent gas chambers and the leakage degree and speed; the comparison with the initial pressure value is used to automatically report the gas chamber where SF6 leakage occurs, and the online monitoring pressure data is compared with the stored pressure data. The difference is calculated corresponding to the initial value of the air chamber pressure, and when the difference exceeds the threshold value, it is automatically reported; the pressure comparison and pressure mutation judgment at different times are used to reflect the air chamber pressure at different times of the same air chamber, and calculate each air chamber SF6 leakage rate, which is calculated by the second-order algorithm; the pressure comparison of adjacent air chambers is calculated by the second-order algorithm;

8) Over-limit alarm step, when it is judged over-limit, perform over-limit alarm;

9) Data storage, storing pressure data, including initial pressure value and historical pressure value;

10) In the display step, reports and curves are generated according to the pressure value, so as to predict the SF6 leakage trend by analyzing the data.

Further, in step 6) in the data preprocessing step, including:

A) The absolute pressure calculation of the data preprocessing module, the absolute pressure calculation adopts the formula: P=0.098×(0.58×10 ^-3 γT(1+B)-γ ² A);

A=0.764×10 ^-3 (1-0.727×10 ^-3 γ);

B=2.51×10 ^-3 γ (1-0.846×10 ^-3 γ);

Among them: P: absolute pressure value, unit: Mpa;

γ: gas density, unit: kg/m ³ ;

T: absolute temperature, unit K;

And the temperature coefficient of gas pressure is obtained from the above formula:

k＝0.098×(0.58×10 ^-3 γ(1+B)), unit: Mpa/℃;

The gas density is calculated according to the gas density at the initial installation, or the pressure and temperature by the above formula; during operation, the pressure temperature coefficient k value is calculated by the formula, combined with the actual temperature value, the gas pressure is uniformly converted to a temperature of 20°C The pressure, and then carry out the comparative analysis of the follow-up pressure to remove the temperature factor and make the calculation more accurate;

B) Calculation of the pressure difference change between the manual transcription data and the online monitoring data: the difference calculation formula is:

P″ _AH = P′ _AH 2-P′ _AH 1

Among them: P′ _AH 1=P _A 1-P _H 1

P' _AH 2 = P _A 2 - P _H 2

P _A 1: At time 1, the air chamber pressure collected by online monitoring;

P _H 1: At time 1, the pressure of the air chamber transcribed manually;

P _A 2: At time 2, the air chamber pressure collected by online monitoring;

P _H 2: At time 2, manually transcribed air chamber pressure.

When P″ _AH ≥ 0.02, it is considered that the online monitoring data is abnormal, and a reminder needs to be confirmed manually.

Step 3) also includes comparing pressure at different times, judging sudden changes in pressure, and comparing with the initial pressure value;

The comparison with the initial pressure value is used to automatically report the gas chamber where SF6 leakage occurs. It calculates the difference between the online monitoring pressure data and the stored initial pressure value of the corresponding gas chamber. When the difference exceeds the threshold value, it will automatically report ;

Pressure comparison and pressure mutation judgment at different times are used to reflect the pressure of the same gas chamber at different times and calculate the SF6 leakage rate of each gas chamber;

It is calculated by a second-order algorithm;

The pressure comparison of adjacent air chambers, the pressure comparison at different times and the judgment of pressure mutation are all calculated by the second-order algorithm.

The technical scheme adopts multiple methods for comparison and analysis, monitors from multiple angles, and can detect abnormalities in time, thereby ensuring the stability of its working pressure.

Beneficial effect:

1. This technical solution realizes the effective monitoring of the pressure of each air chamber, monitors and analyzes the pressure from multiple angles, detects small changes in the pressure of the air chamber in time, and detects defects before the equipment occurs in serious situations such as low pressure alarms. It is beneficial to deal with hidden dangers of equipment safety in advance.

2. This technical solution compensates the SF6 pressure for temperature and atmospheric pressure; combined with manual transcription data, it corrects the online monitoring data, eliminates the influence of temperature and atmospheric pressure, and effectively improves the accuracy of the data.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the present invention.

Fig. 2 is a block diagram of the connection structure of the present invention.

Fig. 3 is a flow chart of the present invention.

detailed description

The technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings.

As shown in Figure 1, the GIS equipment SF6 online monitoring system includes:

Manual transcription data input module: used for the input of manual transcription data;

The pressure acquisition module is used to acquire the pressure of each gas chamber on the substation GIS equipment;

A temperature acquisition module, configured to acquire the temperature in each or more air chambers;

Atmospheric pressure monitoring module for collecting atmospheric pressure;

The data analysis module is used to perform data analysis on the information obtained by the pressure acquisition module, temperature acquisition module and atmospheric pressure monitoring module, and obtain the corresponding air chamber pressure, temperature and atmospheric pressure;

The data preprocessing module obtains the absolute pressure according to the pressure of the gas chamber and the atmospheric pressure, and compensates the absolute pressure according to the corresponding temperature in the gas chamber; combined with the manual transcription data, the online monitoring data is corrected;

The pressure monitoring and analysis module is used to analyze and judge the data processed by the data preprocessing module; it includes a pressure over-limit judgment sub-module for pressure over-limit judgment, and an adjacent air chamber pressure comparison for adjacent air chamber pressures. Comparison sub-module, pressure comparison sub-module at different times for pressure comparison at different times, initial pressure comparison sub-module for comparison with the initial pressure value, pressure mutation judgment sub-module for pressure mutation judgment, adjacent air chamber pressure comparison It is used to reflect the leakage between adjacent gas chambers and its leakage degree and speed; the comparison with the initial pressure value is used to automatically report the gas chamber where SF6 leakage occurs, and it compares the online monitoring pressure data with the stored corresponding gas chamber pressure The initial value is calculated as a difference, and when the difference exceeds the threshold value, it is automatically reported; the pressure comparison and pressure mutation judgment at different times are used to reflect the pressure of the same gas chamber at different times, and calculate the SF6 leakage rate of each gas chamber. It is calculated by the second-order algorithm; the pressure comparison of adjacent air chambers is calculated by the second-order algorithm;

The over-limit alarm module, when the pressure monitoring and analysis module judges over-limit, it will issue an over-limit alarm;

The data storage module is a data storage module for storing data.

This technical solution realizes the effective monitoring of the pressure of each air chamber, monitors and analyzes the pressure from multiple angles, discovers small changes in the pressure of the air chamber in time, and can find defects before the equipment occurs in serious situations such as low pressure alarms, which is beneficial Deal with equipment security risks in advance.

This technical solution compensates the SF6 pressure for temperature and atmospheric pressure; combined with manual transcription data, the online monitoring data is corrected. Effectively improve the accuracy of data. Overcome some problems that existed before, such as: "The pressure data collected by the online monitoring sensor probe is relative pressure, without considering the change of atmospheric pressure. Some sensors also do not consider the temperature factor, and the collected data will change with the change of temperature. Large fluctuations. At the same time, the online monitoring system often has data errors due to problems such as probes.”

As shown in Figure 2, in order to improve the accuracy and reliability of monitoring, the pressure acquisition module includes a plurality of SF6 pressure monitors, and each air chamber of the GIS equipment is provided with an SF6 pressure monitor to collect the pressure of each air chamber Pressure value.

When the substation GIS equipment is 1000KV GIS equipment, each 1000kV GIS circuit breaker unit is equipped with a junction box, which is used to connect all SF6 pressure monitors of this circuit breaker unit. The junction box is set in a SF6 online monitoring system cabinet, and the SF6 online monitoring system cabinet is connected to 1000kV GIS status monitoring information. The communication module of the system.

When the substation GIS equipment is 500kV GIS equipment, each 500kV GIS circuit breaker unit is equipped with one SF6 monitoring sub-IED, and at the same time is equipped with a 500kV SF6 online monitoring main IED, and the 500kV SF6 online monitoring main IED is connected with the SF6 monitoring sub-IED for Gather status monitoring information and upload it to the integrated monitoring system.

In order to improve data security, the GIS equipment SF6 online monitoring system is independently networked in Zone II, and the information data is connected to the comprehensive application server using the DL/T860 (IEC 61850) protocol, and the communication gateway in Zone II adopts the DL/T634.5104 protocol and Dispatch communication at all levels and transmit online monitoring information.

As shown in Figure 3, the online monitoring method of the present invention comprises the following steps:

1) Manually transcribing the data step, manually transcribing the SF6 density table data at regular intervals, and importing the manually transcribed SF6 density table data into the system through the manual transcription data input module;

2) In the pressure collection step, the SF6 pressure monitor collects the pressure of each gas chamber on the substation GIS equipment;

3) The temperature collection step is to collect the temperature of each air chamber or several air chambers therein;

4) The atmospheric pressure monitoring module collects real-time atmospheric pressure;

5) The data analysis step is to perform data analysis on the information obtained by the pressure acquisition module, the temperature acquisition module and the atmospheric pressure monitoring module, and obtain the corresponding air chamber pressure, temperature and atmospheric pressure;

6) Data preprocessing step, obtain the absolute pressure according to the air chamber pressure and atmospheric pressure, and compensate the absolute pressure according to the corresponding temperature in the air chamber; calculate the difference between the manual transcription data and the online monitoring data, when the manual transcription data and the online monitoring data When the difference between the monitoring data is greater than the threshold, confirm whether the online monitoring probe is faulty, and replace the online monitoring data with manual transcription data, and correct the online monitoring data;

It includes two main contents: (1) temperature and atmospheric pressure compensation for SF6 pressure; (2) correction of online monitoring data combined with manual transcription data.

(1) Temperature and atmospheric pressure compensation. The pressure collected by the sensor is relative pressure, and the factor of atmospheric pressure is not considered; the pressure collected by some sensor probes has not been temperature compensated and needs to be compensated.

(2) The on-line monitoring sensor probe often fails to cause data errors, while the SF6 density meter installed on site works very stably and rarely has problems. Therefore, the data of the manual transcription of the density table twice a month is imported into the system, and the errors of the online monitoring data are corrected through comparative analysis. When the failure of the online monitoring probe is confirmed, the online monitoring data is replaced by manual transcription data.

7) The pressure monitoring and analysis step is to analyze and judge the data processed by the data preprocessing module; including the judgment of pressure exceeding the limit, the comparison of the pressure of adjacent air chambers, the comparison of pressure at different times, the comparison with the initial pressure value, the judgment of sudden pressure changes, and the judgment of adjacent air chambers. The comparison of gas chamber pressure is used to reflect the leakage between adjacent gas chambers and the leakage degree and speed; the comparison with the initial pressure value is used to automatically report the gas chamber where SF6 leakage occurs, and the online monitoring pressure data is compared with the stored pressure data. The difference is calculated corresponding to the initial value of the air chamber pressure, and when the difference exceeds the threshold value, it is automatically reported; the pressure comparison and pressure mutation judgment at different times are used to reflect the air chamber pressure at different times of the same air chamber, and calculate each air chamber SF6 leakage rate, which is calculated by the second-order algorithm; the pressure comparison of adjacent air chambers is calculated by the second-order algorithm;

8) Over-limit alarm step, when it is judged over-limit, perform over-limit alarm;

9) Data storage, storing pressure data, including initial pressure value and historical pressure value;

10) In the display step, reports and curves are generated according to the pressure value, so as to predict the SF6 leakage trend by analyzing the data.

Further, in step 6) in the data preprocessing step,

include:

A) The absolute pressure calculation of the data preprocessing module, the absolute pressure calculation adopts the formula: P=0.098×(0.58×10 ^-3 γT(1+B)-γ ² A);

A=0.764×10 ^-3 (1-0.727×10 ^-3 γ);

B=2.51×10 ^-3 γ (1-0.846×10 ^-3 γ);

Among them: P: absolute pressure value, unit: Mpa;

γ: gas density, unit: kg/m ³ ;

T: absolute temperature, unit K;

And the temperature coefficient of gas pressure is obtained from the above formula:

k=0.098×(0.58×10 ^-3 γ(1+B)), unit: Mpa/℃;

The gas density is calculated according to the gas density at the time of initial installation, or the pressure and temperature from the above formula; during operation, the pressure temperature coefficient k value is calculated by the formula, combined with the actual temperature value, the gas pressure is uniformly converted to a temperature of 20°C The pressure, and then carry out the comparative analysis of the follow-up pressure to remove the temperature factor and make the calculation more accurate;

Online monitoring collects real-time atmospheric pressure and SF6 pressure and temperature of each gas chamber at the same time (because the temperature of the GIS equipment in the whole station is similar, some use the same temperature value), and compensates the pressure of each gas chamber. Generally, what is collected by online monitoring or indicated on the pressure gauge is the gauge pressure. However, absolute pressure is used when calculating parameters or checking curves, and the difference between the two is 1 atmosphere. Therefore, the collected pressure value is added to the atmospheric pressure value at that time to obtain the absolute pressure, and then the absolute pressure is used for temperature compensation.

B) Calculation of the pressure difference change between the manual transcription data and the online monitoring data: the difference calculation formula is:

P″ _AH = P′ _AH 2-P′ _AH 1

Among them: P′ _AH 1=P _A 1-P _H 1

P' _AH 2 = P _A 2 - P _H 2

P _A 1: At time 1, the air chamber pressure collected by online monitoring;

P _H 1: At time 1, the pressure of the air chamber transcribed manually;

P _A 2: At time 2, the air chamber pressure collected by online monitoring;

P _H 2: At time 2, manually transcribed air chamber pressure.

When P″ _AH ≥ 0.02, it is considered that the online monitoring data is abnormal, and a reminder needs to be confirmed manually.

Among them, the comparison with the initial pressure value is used to automatically report the gas chamber where SF6 leakage occurs. It calculates the difference between the online monitoring pressure data and the stored initial value of the corresponding gas chamber pressure. When the difference exceeds the threshold value, it automatically reported;

Pressure comparison and pressure mutation judgment at different times are used to reflect the pressure of the same gas chamber at different times and calculate the SF6 leakage rate of each gas chamber;

The pressure comparison of adjacent air chambers, the pressure comparison at different times and the judgment of pressure mutation are all calculated by the second-order algorithm.

The on-line monitoring sensor probes often fail to cause data errors, while the SF6 density meter installed on site works very stably and rarely has problems. Therefore, the data of the manual transcription of the density table twice a month is imported into the system, and the errors of the online monitoring data are corrected through comparative analysis. When the failure of the online monitoring probe is confirmed, the online monitoring data is replaced by manual transcription data. Since there is a certain error between the online monitoring and the pressure gauge, it is necessary to monitor the change in the pressure difference between the two rather than the pressure difference itself to verify the correctness of the data.

Below, some work steps are further described in detail:

1. Data collection and alarm

Each air chamber has its own operating conditions and rated pressure (the rated pressure of most air chambers is the same, and there are several types of rated pressure in total), and the integrated monitoring system centrally displays the collected air chamber pressure. The operation and maintenance personnel can check the SF6 gas pressure value of each gas chamber at each time through the telemetry information table, and compare the value with the preset alarm pressure value. When it is lower than the alarm pressure or the rated pressure value, it will immediately alarm. Simultaneously release briefing information.

2. Horizontal comparison of data

Each air chamber of GIS has adjacent air chambers connected to it, and these air chambers are separated by insulating medium. There is a certain pressure difference between adjacent air chambers. When the pressure difference exceeds a certain value, a large pressure may be applied to the separation medium and cause damage. Therefore, it should be monitored that the pressure difference between adjacent air chambers should not exceed the relevant specified value.

If there is leakage in the insulation interval between adjacent air chambers, the gas will flow from the air chamber with high pressure to the air chamber with low pressure. By monitoring the pressure difference between adjacent air chambers, it can be detected whether there is leakage in the interval between air chambers. So as to predict the leakage of SF6 gas pressure.

Since the rated pressure itself may be different between adjacent air chambers, for example, the rated pressure of the switch air chamber is higher than the rated pressure of the current transformer air chamber. Moreover, the pressure of the gas filled in the initial installation of the gas chambers is not the same, and a pure comparison of the pressure difference between adjacent gas chambers cannot correctly reflect abnormalities such as leakage. Therefore, the concept of second-order derivation should be used to deal with the pressure values of adjacent air chambers, that is, to calculate the variation of the pressure difference between adjacent air chambers.

Assume, A air chamber and B air chamber are two adjacent air chambers. Then the pressure difference between two adjacent air chambers is calculated as follows:

P″ _AB = P′ _AB 2-P′ _AB 1

Among them: P′ _AB 1=P _A 1-P _B 1

P' _AB 2 = P _A 2 - P _B 2

P _A 1: At time 1, the pressure of air chamber A;

P _B 1: at time 1, the pressure of B air chamber;

P _A 2: At time 2, the pressure of air chamber A;

P _B 2: At time 2, the pressure of B air chamber.

In practice, P′ _AB 1 and P′ _AB 2 cannot directly represent the gas chamber. Only when the variation of the pressure difference between the two air chambers reaches a large value, it means that the relative pressure of the two air chambers has changed greatly, that is, when the value of P″ _AB is large, it means that there is a leak or leakage between the two air chambers. One of the air chambers has a large leakage. In the formula, P′ _AB 1 is generally taken as the pressure difference between adjacent air chambers when the equipment is put into operation and is relatively stable, and is recorded in the database as a constant.

If two air chambers leak at the same speed at the same time, the value of P″ _AB is basically zero. However, since the air chambers are connected to each other, there is always an adjacent air chamber on the other side of any air chamber. Therefore, there will always be a large change in the pressure difference between the leaking air chamber and another adjacent air chamber, and the abnormality can still be detected.

3. Longitudinal comparison of data

The SF ₆ leakage rate of the GIS gas chamber has relevant regulations. The annual leakage rate of SF ₆ equipment put into operation for the first time shall not exceed 1%, and the annual leakage rate shall not exceed 0.5% thereafter. After the equipment is put into operation and is relatively stable, record its original pressure value, and use the pressure value collected by online monitoring to calculate the SF ₆ leakage rate of each gas chamber, so as to monitor whether the airtightness of the equipment meets the requirements of relevant regulations and standards Require.

Since the pressure of SF ₆ gas will change with the change of temperature, although the SF ₆ pressure collected in the system has been temperature compensated, there is still a certain error. In order to eliminate this effect, the pressure of the same air chamber at different times (same time on different days) can be compared.

By comparing the SF6 gas online monitoring data of the whole substation with the data of the same collection point at different times, the difference is calculated. By comparing the difference between the current value and the initial value, the cumulative change of the air chamber pressure can be reflected, so as to predict the slow leakage of the air chamber pressure.

The longitudinal comparison criteria for the same air chamber pressure are as follows:

Criterion for comparison with the initial value: ΔP ₀ ＝P _pre -P ₀ ≥ΔP _0set

Window period comparison criterion: ΔP _t ＝ P _pre -P _pre-t ≥ ΔP _tset

P _pre : the air chamber pressure value collected at the current moment;

P ₀ : the initial pressure value of the air chamber;

ΔP _0set : initial pressure comparison alarm set value;

P _pre-t : the air chamber pressure value before the window period;

ΔP _tset : Window period pressure comparison alarm setting value.

The window period is divided into weeks, months, quarters, years and variable. The variable window period can be set as a time period in units of hours, generally set to 24 hours. The window period is fixed, but data comparison is performed in real time and every time. When the pressure value of the air chamber sent by the online monitoring system is received, it is immediately compared with the pressure value of the air chamber at this moment in the database for one week, one month, one season, one year and the set number of hours. After the next data reception, it is compared with the pressure value at the same moment before the window period. This method realizes the real-time comparison of the gas chamber pressure instead of the comparison at fixed time intervals. In practical applications, two modes are used: the same time as the previous day and the comparison with the initial pressure of the equipment.

4. Display of online monitoring data analysis results

In addition to realizing the SF6 online detection data analysis functions such as SF6 gas chamber pressure display and alarm, adjacent interval air chamber pressure comparison, and same interval air chamber pressure comparison at different times, the system also provides online monitoring data curve and report browsing functions. Both curves and reports can be printed and exported electronically.

4.1 Curve

For the data stored by telemetry, there is a screen to display the current telemetry value, and you can view real-time curves and historical curves. The real-time curve starts from the current time, gradually receives the uploaded data, and draws the pressure value curve according to the time axis. The historical curve calls out historical data from the database according to the set time interval and draws it into a curve.

The curve has a comparison function, that is, it is compared with the pressure value of the previous day or the same time period of the previous few days to intuitively display the change of pressure. At the same time, other interval curves can be added for comparison, and it has the function of comparing multiple curves. The curve can be stretched horizontally and vertically, and the data of suspicious time periods can be focused on analysis.

4.2 Report

The reports that can be realized by the integrated monitoring system include: air chamber pressure report, adjacent air chamber pressure difference report, air chamber pressure difference report at different times, etc. All the above reports have daily report, monthly report and annual report. The daily report takes the data value at every hour, the monthly report takes the data value at 0:00 every day, and the annual report takes the data value at 0:00 on the 1st of each month. If the data in the report deviates from the alarm value given by the user (telemetry limit value), it will be displayed in different colors to remind the user to pay attention.

The report can be viewed and printed in real time, and can be output and saved in the form of an excel form, and then copied from the monitoring system using ftp to facilitate data export and further utilization and processing.

This technical solution can be implemented based on the monitoring background, real-time processing of data, real-time alarm, and realization of SF ₆ pressure horizontal comparison (pressure comparison of adjacent gas chambers) and vertical comparison (pressure over-limit judgment, comparison with initial pressure, pressure mutation judgment), Comprehensive analysis and processing of the SF ₆ pressure value collected by the online monitoring system. The effective monitoring of the pressure of each air chamber can detect small changes in the pressure of the air chamber in time, and defects can be found before the equipment has a serious situation such as a low pressure alarm, which is beneficial to deal with potential safety hazards of the equipment in advance.

At the same time, the results of advanced application analysis of station-side online monitoring data analysis can be sent to the state evaluation center through the comprehensive data network, providing data support for UHV substation state-of-the-art maintenance. With the development of monitoring system and computer technology, the integrated monitoring system will gradually adopt the modular design concept, and its functions will be perfected day by day. The modular structure allows the monitoring system to expand other related advanced application functions such as online monitoring while ensuring the basic monitoring functions. At that time, the data collected by the online monitoring system will be used in a deeper level, and the hidden meaning in the online monitoring data will be more excavated.

The GIS equipment SF6 on-line monitoring system shown in above Fig. 1-3 and working method thereof are concrete embodiments of the present invention, have embodied the substantive characteristics and progress of the present invention, can according to actual use needs, under the enlightenment of the present invention , equivalent modification of its shape, structure, etc., are all within the scope of protection of this scheme.

Claims (10)

1.GIS equipment SF6 on-line monitoring systems, it is characterised in that including：

Artificial copy data input module：Input for artificial copy data；

Pressure acquisition module, the pressure for gathering each air chamber in transformer station's GIS device；

Temperature collect module, for gathering the temperature in each or multiple air chambers；

Atmospheric pressure monitoring modular, for gathering atmospheric pressure；

Data resolution module, for being carried out to the information that pressure acquisition module, temperature collect module, atmospheric pressure monitoring modular are obtained Data are parsed, and obtain corresponding air chamber pressure, temperature and atmospheric pressure；

Data preprocessing module, obtains absolute pressure, according to the corresponding temperature in air chamber to exhausted according to air chamber pressure, atmospheric pressure Pressure is compensated；And artificial copy data is combined, online monitoring data is modified；

Pressure monitoring analysis module, for carrying out analysis judgement to the data after data prediction resume module；It includes being used for The out-of-limit judging submodule of pressure of the out-of-limit judgement of pressure, for adjacent air cells pressure ratio compared with adjacent air cells pressure ratio compared with submodule Block, for not in the same time pressure ratio compared with not initial pressure of the pressure ratio compared with submodule, for being compared with initial pressure value in the same time Power comparison sub-module, the pressure jump judging submodule judged for pressure jump, adjacent air cells pressure ratio are relatively used to reflect phase Leakage and its leakiness and speed between adjacent air chamber；Comparison with initial pressure value is used for the automatic generation SF6 that quotes and leaked Air chamber, the pressure data of on-line monitoring is carried out mathematic interpolation by it with the corresponding air chamber pressure initial value stored, when difference is super When crossing thresholding, quote automatically；Not in the same time pressure ratio compared with and pressure jump judge, for reflecting the gas of same air chamber not in the same time Chamber pressure, calculates each air chamber SF6 slips, it is calculated by second order algorithm；Adjacent air cells pressure ratio is compared with passing through second order algorithm Calculate；

Off-limit alarm module, when pressure monitoring analysis module judges more to prescribe a time limit, carries out off-limit alarm；

Data memory module, the data memory module for data storage.

2. GIS device SF6 on-line monitoring systems according to claim 1, it is characterised in that：Data preprocessing module is in meter When calculating absolute pressure, using formula：P=0.098 × (0.58 × 10^-3γT(1+B)-γ²A)；

A=0.764 × 10^-3(1-0.727×10^-3γ)；

B=2.51 × 10^-3γ(1-0.846×10^-3γ)；

Wherein：P：Absolute pressure value, unit：Mpa；

γ：Gas density, unit：kg/m³；

T：Absolute temperature, unit K；

And the temperature coefficient of gas pressure is obtained by above formula：

K=0.098 × (0.58 × 10^-3γ (1+B)), unit：Mpa/℃.

Gas density is according to gas density during first dress, or according to pressure and temperature by obtained by above formula Extrapolation；Operation In, calculated by formula and obtain pressure-temperature coefficient k values, with reference to actual temperature value, by the unified conversion of gas pressure to 20 DEG C of temperature Under pressure, then carry out the comparative analysis of packing pressure, to eliminate temperature factor, make to be accurately calculated.

3. GIS device SF6 on-line monitoring systems according to claim 1, it is characterised in that：On-line monitoring system also includes Display module, after the completion of analysis, display module is used to generate form and curve, to carry out SF6 leakage trend to the analysis of data Anticipation.

4. GIS device SF6 on-line monitoring systems according to claim 1, it is characterised in that：Described pressure acquisition module Including multiple SF6 pressure monitors, each air chamber of GIS device is equipped with a SF6 pressure monitors to gather each air chamber Pressure value.

5. GIS device SF6 on-line monitoring systems according to claim 2, it is characterised in that：When transformer station, GIS device is During 1000KV GIS devices, each 1000kV GIS breaker units configure 1 terminal box, for accessing this breaker unit institute There are SF6 pressure monitors.

6. GIS device SF6 on-line monitoring systems according to claim 3, it is characterised in that：Described terminal box is located at one In SF6 on-line monitoring system cabinets, SF6 on-line monitoring systems cabinet access 1000kV GIS status monitoring informations, described SF6 is online Monitoring system cabinet is provided with the communication module for being used for that 1000kV GIS status monitoring informations to be uploaded to integrated monitoring system.

7. GIS device SF6 on-line monitoring systems according to claim 2, it is characterised in that：When transformer station, GIS device is During 500kV GIS devices, each 500kV GIS breaker units configure 1 SF6 and monitor sub- IED, while configuring 1 500kV SF6 monitors main IED on-line, and 500kV SF6 monitor main IED on-line and are connected with the sub- IED of SF6 monitorings for converging status monitoring information After be uploaded to integrated monitoring system.

8. GIS device SF6 on-line monitoring systems according to claim 1, it is characterised in that：GIS device SF6 is monitored on-line System accesses integrated application server, IIth area in II area's independence networking, information data using DL/T860 (IEC 61850) agreement Communication network shutdown is using DL/T634.5104 stipulations and dispatching communications at different levels, transmission on-line monitoring information.

9. using the on-line monitoring method of the GIS device SF6 on-line monitoring systems described in claim 1-5 any claims, It is characterized in that comprising the following steps：

1) SF6 density meters data are manually made a copy of by artificial copy data step at regular intervals, and will manually be made a copy of SF6 density meters data pass through artificial copy data input module import system；

2) pressure of each air chamber in pressure acquisition step, SF6 pressure monitors collection transformer station GIS device；

3) temperature acquisition step, the collection of trip temperature during to each air chamber or several air chambers therein；

4) atmospheric pressure monitoring modular, gathers Real-Time Atmospheric pressure；

5) data analyzing step, to being carried out to the information that pressure acquisition module, temperature collect module, atmospheric pressure monitoring modular are obtained Data are parsed, and obtain corresponding air chamber pressure, temperature and atmospheric pressure；

6) data prediction step, obtains absolute pressure, according to the corresponding temperature pair in air chamber according to air chamber pressure, atmospheric pressure Absolute pressure is compensated；Calculate the difference between artificial copy data and online monitoring data, when artificial copy data with When difference between line Monitoring Data is more than threshold value, it is confirmed whether that on-line monitoring probe breaks down, and with artificial copy data Online monitoring data is substituted, online monitoring data is modified,；

7) data after data prediction resume module are carried out analysis judgement by pressure monitoring analytical procedure；It is out-of-limit including pressure Judge, adjacent air cells pressure ratio compared with, not in the same time pressure ratio compared with, compared with initial pressure value, pressure jump judgement, adjacent air cells Pressure ratio is compared with for reflecting leakage and its leakiness and speed between adjacent air cells；Comparison with initial pressure value is used for certainly Dynamic to quote the air chamber for occurring SF6 leakages, it carries out the pressure data of on-line monitoring with the corresponding air chamber pressure initial value stored Mathematic interpolation, when difference exceedes thresholding, is quoted automatically；Not in the same time pressure ratio compared with and pressure jump judge, it is same for reflecting The air chamber pressure of one air chamber not in the same time, calculates each air chamber SF6 slips, it is calculated by second order algorithm；Adjacent air cells pressure Power compares to be calculated by second order algorithm；

8) off-limit alarm step, when judging more to prescribe a time limit, carries out off-limit alarm；

9) data storage, stores pressure data, and pressure data includes initial pressure value, historical pressures value；

10) step is shown, form and curve are generated according to pressure value, to carry out SF6 leakage trend anticipations to the analysis of data.

10. the on-line monitoring method of GIS device SF6 on-line monitoring systems according to claim 9, it is characterised in that Step 6) in data prediction step, including：

A) absolute pressure of data preprocessing module is calculated, and absolute pressure calculates and uses formula：P=0.098 × (0.58 × 10^-3 γT(1+B)-γ²A)；

A=0.764 × 10^-3(1-0.727×10^-3γ)；

B=2.51 × 10^-3γ(1-0.846×10^-3γ)；

Wherein：P：Absolute pressure value, unit：Mpa；

γ：Gas density, unit：kg/m³；

T：Absolute temperature, unit K；

And the temperature coefficient of gas pressure is obtained by above formula：

K=0.098 × (0.58 × 10^-3γ (1+B)), unit：Mpa/℃；

Gas density is according to gas density during first dress, or according to pressure and temperature by obtained by above formula Extrapolation；Operation In, calculated by formula and obtain pressure-temperature coefficient k values, with reference to actual temperature value, by the unified conversion of gas pressure to 20 DEG C of temperature Under pressure, then carry out the comparative analysis of packing pressure, to eliminate temperature factor, make to be accurately calculated；

B) artificial pressure differential variable quantity between copy data and online monitoring data is calculated：Mathematic interpolation formula is：

P″_AH=P '_AH2-P″_AH1

Wherein：P″_AH1=P_A1-P_H1

P′_AH2=P_A2-P_H2

P_A1：At the moment 1, monitor the air chamber pressure of collection on-line；

P_H1：Moment 1, the air chamber pressure manually made a copy of；

P_A2：At the moment 2, monitor the air chamber pressure of collection on-line；

P_H2：Moment 2, the air chamber pressure manually made a copy of.

As P "_AHWhen >=0.02, it is believed that online monitoring data is abnormal, and sending prompting needs manual confirmation.