Online Prediction System and Method for SF6 Gas Equipment Leakage in Substation

Abstract

The present invention discloses an on-line prediction system and method for leakage of SF6 gas equipment in a substation. The on-line prediction system includes a plurality of SF6 gas monitoring terminals, and the plurality of SF6 gas monitoring terminals are respectively installed on a plurality of SF6 circuit breakers one by one. The SF6 gas monitoring terminals are respectively provided with a first detection component for monitoring the external environmental temperature and a second detection component for monitoring the SF6 gas temperature. The SF6 gas monitoring terminals are communicatively connected to a mobile terminal through a 4G short message alarm module, and the SF6 gas monitoring terminals are communicatively connected to a remote control host. By configuring SF6 gas monitoring terminals on SF6 gas equipment in the substation, the temperature difference between the SF6 gas and the external environment is determined by using the first detection component and the second detection component. When the temperature difference is within the normal threshold range, the effective pressure value of the SF6 gas equipment on the current day can be determined, avoiding the problem of distorted pressure value statistics by traditional maintenance personnel, and realizing air replenishment alarm for the SF6 gas equipment and prediction of the optimal air replenishment time.

Description

Technical Field

[0001] The present invention relates to the technical field of substation safety monitoring, and particularly to an on-line prediction system and method for leakage of SF6 gas equipment in a substation. Background Art

[0002] Leakage problem of SF6 gas equipment in a substation: Due to various reasons, there is a leakage phenomenon in SF6 gas equipment. The longer the equipment operates, the more serious the leakage is. When the gas in the equipment leaks to the set gas replenishment value, a gas replenishment alarm signal is sent. It can be known from the SF6 gas temperature-pressure relationship table that temperature change has a great influence on the pressure value. Although SF6 density meters or SF6 density relays with temperature compensation have been popularized in equipment, the compensation system has the problem that it needs to be kept at a constant temperature for a long time to achieve temperature compensation, resulting in distortion of the pressure values statistically obtained by operation and maintenance personnel. Therefore, there are also many alarm signals obtained in the two seasons of winter and summer with large temperature differences, and at this time, there are great potential safety hazards in the gas replenishment work. Therefore, it is urgent to predict when the equipment will send an alarm signal and the best timing for gas replenishment. Summary of the Invention

[0003] Aiming at the technical problem that although the current SF6 density meter has a temperature compensation system, the compensation system has the problem that it needs to be kept at a constant temperature for a long time to achieve temperature compensation, resulting in distortion of the pressure values statistically obtained by operation and maintenance personnel. Therefore, there are also many alarm signals obtained in the two seasons of winter and summer with large temperature differences, and at this time, there are great potential safety hazards in the gas replenishment work, this application proposes an on-line prediction system and method for leakage of SF6 gas equipment in a substation.

[0004] The present invention achieves the above object through the following technical solutions:

[0005] This application discloses an on-line prediction system for leakage of SF6 gas equipment in a substation, including a plurality of SF6 gas monitoring terminals. The plurality of SF6 gas monitoring terminals are respectively and correspondingly installed on a plurality of SF6 circuit breakers. Each SF6 gas monitoring terminal is provided with a first detection component for monitoring the external environmental temperature and a second detection component for monitoring the SF6 gas temperature. The SF6 gas monitoring terminal is communicatively connected to a mobile terminal through a 4G short message alarm module. The SF6 gas monitoring terminal includes an SF6 density meter and a connection component. The lower part of the SF6 density meter is communicated with the connection component; a control component is arranged on the connection component. The first detection component and the second detection component are respectively arranged on the connection component. The first detection component and the second detection component are both electrically connected to the control component. The control component is communicatively connected to the mobile terminal through the 4G short message alarm module. The control component is communicatively connected to a remote control host through an RS485 communication bus.

[0006] The present application configures an SF6 gas monitoring terminal on the SF6 gas equipment in the substation, and uses a first detection component and a second detection component to determine the temperature difference between the SF6 gas and the external environment. When the temperature difference is within a normal threshold range, the effective pressure value of the SF6 gas equipment on that day can be determined, thereby avoiding the problem of distortion of pressure values ​​by traditional operation and maintenance personnel. In addition, the application can realize gas replenishment alarm for the SF6 gas equipment and prediction of the optimal gas replenishment time, perform gas replenishment operations according to the optimal gas replenishment time, and reduce the safety hazards of gas replenishment work.

[0007] Preferably, the connecting assembly is provided with a first regulating member for controlling the flow of SF6 gas into the SF6 density meter and a second regulating member for controlling the exhaustion of SF6 gas in the SF6 density meter, and the first regulating member and the second regulating member are both electrically connected to the control assembly.

[0008] Preferably, the connecting assembly includes a connecting pipe, a first connecting base is provided at the lower part of the SF6 density meter, a second connecting base is provided at the upper part of the connecting pipe, the first connecting base and the second connecting base are detachably connected, and the SF6 density meter is connected to the connecting pipe; the control assembly, the first detection assembly, the second detection assembly, the first adjustment member and the second adjustment member are respectively arranged on the connecting pipe.

[0009] Preferably, the first detection component is arranged inside the connecting tube, the second detection component is arranged outside the connecting tube, a connecting head is arranged on one side of the connecting tube, an air inlet is opened on the connecting head, the first adjusting member is arranged in the air inlet, an exhaust port is arranged at the lower part of the connecting tube, and the second adjusting member is arranged in the exhaust port.

[0010] Preferably, the first detection component includes a first temperature sensor, the second detection component includes a second temperature sensor, the first adjustment component includes a first solenoid valve, the second adjustment component includes a second solenoid valve, and the control component includes a control panel, which is arranged on the outside of the connecting pipe, and the control panel is electrically connected to the first temperature sensor, the second temperature sensor, the first solenoid valve and the second solenoid valve, respectively.

[0011] Preferably, an LCD display screen is provided on the control panel. A storage battery and a DSP signal processor are provided inside the control panel. The DSP signal processor is electrically connected to the first temperature sensor, the second temperature sensor, the first solenoid valve, and the second solenoid valve respectively. The DSP signal processor is electrically connected to the SF6 density meter through an A / D signal converter. The DSP signal processor is communicatively connected to the mobile terminal through a 4G SMS alarm module. The DSP signal processor is communicatively connected to the remote control host through an RS485 communication bus.

[0012] An on-line prediction method for SF6 gas equipment leakage in a substation includes the following steps:

[0013] S1. Obtain the effective pressure value of the SF6 gas equipment on the current day;

[0014] S2. Calculate the gas leakage amount, gas leakage rate, and leakage growth rate of the SF6 gas equipment according to the effective pressure value obtained daily;

[0015] S3. Calculate the annual leakage rate according to the gas leakage amount, gas leakage rate, and leakage growth rate. Compare the annual leakage rate with the preset standard annual leakage rate. If the annual leakage rate exceeds the standard annual leakage rate, mark the SF6 gas equipment and include it in the early warning library;

[0016] S4. Draw a gas pressure trend chart of the SF6 gas equipment for the SF6 gas equipment marked in the early warning library according to the daily updated pressure value combined with the gas leakage amount, leakage rate, and leakage growth rate;

[0017] S5. Predict the air replenishment alarm time of the SF6 gas equipment according to the gas pressure trend chart of the SF6 gas equipment marked in the early warning library;

[0018] S6. Determine the best air replenishment time according to the air replenishment alarm time of the SF6 gas equipment, and determine the number of SF6 gas equipment to be replenished during the best air replenishment time;

[0019] S7. When the number of SF6 gas equipment to be replenished reaches the set value, perform centralized air replenishment operations.

[0020] By determining the effective pressure value of the SF6 gas equipment daily, calculating the gas leakage amount, gas leakage rate, and leakage growth rate of the SF6 gas equipment to draw a gas pressure trend chart, it can be predicted when the equipment will trigger a system alarm according to the gas pressure trend chart, and the best air replenishment time is determined 3 months before the trigger system alarm time. When the air replenishment quantity reaches the set quantity for the best air replenishment time, centralized air replenishment can be adopted to reduce the attendance of personnel and vehicles and avoid the load loss caused by the sudden stop of the equipment.

[0021] Preferably, the method for obtaining the effective pressure value of the SF6 gas equipment on the same day in step S1 includes the steps:

[0022] S11. Obtain the external environmental temperature and the SF6 gas temperature;

[0023] S12. If the temperature difference between the external environment and the SF6 gas is within the normal threshold range, the pressure value obtained by the SF6 density table is the effective value on the same day;

[0024] S13. If the temperature difference between the external environment and the SF6 gas exceeds the normal threshold range, compare the SF6 gas temperatures monitored at two time points in the early morning of the same day;

[0025] S14. If the temperature difference between the SF6 gas temperatures monitored at the two time points is less than the set threshold, select the pressure data monitored by the SF6 density table at the latter time point as the effective pressure value on the same day; if the temperature difference between the SF6 gas temperatures monitored at the two time points exceeds the set threshold, select the effective pressure value of the previous day as the effective pressure value on the same day.

[0026] Preferably, the gas leakage amount in step S2 includes the annual gas leakage amount, the monthly gas leakage amount, and the weekly gas leakage amount, the gas leakage rate in step S2 includes the annual gas leakage rate, the monthly gas leakage rate, and the weekly gas leakage rate, and the leakage growth rate in step S2 includes the annual leakage growth rate, the monthly gas leakage growth rate, and the weekly gas leakage growth rate.

[0027] Compared with the prior art, the beneficial effects are as follows:

[0028] 1. In this application, by configuring an SF6 gas monitoring terminal on the SF6 gas equipment in the substation and using the first detection component and the second detection component to determine the temperature difference between the SF6 gas and the external environment, when the temperature difference is within the normal threshold range, the effective pressure value of the SF6 gas equipment on the same day can be determined, avoiding the problem of distorted pressure value statistics by traditional operation and maintenance personnel, and realizing the air replenishment alarm for the SF6 gas equipment and the prediction of the optimal air replenishment time. According to the optimal air replenishment time, air replenishment operations are carried out, reducing the safety hazards of air replenishment work;

[0029] 2. In this application, by determining the effective pressure value of the SF6 gas equipment every day, calculating the gas leakage amount, leakage rate, and leakage growth rate of the SF6 gas equipment, and drawing a gas pressure trend chart, it can be predicted when the equipment will trigger a system alarm according to the gas pressure trend chart, and the time 3 months before the trigger of the system alarm is determined as the optimal air replenishment time. When the air replenishment quantity reaches the set quantity for the optimal air replenishment time, centralized air replenishment can be carried out, reducing the attendance of personnel and vehicles and avoiding the load loss caused by the sudden stop of the equipment;

[0030] By extracting data in the early morning, the measured temperature values and the pressure values after temperature compensation are stable and accurate, avoiding data distortion. Moreover, calculating the leakage rate according to time periods such as months and weeks can sensitively reflect the change in the gas content of the equipment; according to the gas pressure trend chart, air can be supplemented actively to avoid being notified to supplement air temporarily. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0032] Figure 1 It is a schematic structural diagram of the SF6 gas monitoring terminal in the present invention.

[0033] Figure 2 It is a schematic overall working flow chart of the present invention.

[0034] Figure 3 It is a schematic diagram of the acquisition process of the effective pressure value on the same day in the present invention.

[0035] The descriptions of the reference numerals are as follows:

[0036] 1 is an SF6 density meter, 11 is a first connection base, 2 is a connecting pipe, 21 is a second connection base, 3 is a control panel, 4 is a connector, 5 is a first adjusting member, and 6 is a second connecting member. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] This application proposes an online prediction system for SF6 gas equipment leakage in a substation, including a plurality of SF6 gas monitoring terminals. The plurality of SF6 gas monitoring terminals are respectively installed on a plurality of SF6 circuit breakers one by one. The SF6 gas monitoring terminals are respectively provided with a first detection component for monitoring the external environment temperature and a second detection component for monitoring the SF6 gas temperature. The SF6 gas monitoring terminal is communicatively connected to a mobile terminal through a 4G SMS alarm module, and the SF6 gas monitoring terminal is communicatively connected to a remote control host.

[0038] By configuring SF6 gas monitoring terminals on SF6 gas equipment in the substation, this application uses the first detection component and the second detection component to determine the temperature difference between the SF6 gas and the external environment. When the temperature difference is within the normal threshold range, the effective pressure value of the SF6 gas equipment on the same day can be determined, avoiding the problem of distorted pressure value statistics by traditional operation and maintenance personnel. Moreover, it can realize air supplement alarm for SF6 gas equipment and prediction of the best air supplement time, and perform air supplement operations according to the best air supplement time, reducing the safety hazards of air supplement work.

[0039] This application also proposes an online prediction method for SF6 gas equipment leakage in a substation, including the following steps:

[0040] S1. Obtain the effective pressure value of the SF6 gas equipment on the current day;

[0041] S2. Calculate the gas leakage amount, gas leakage rate, and leakage growth rate of the SF6 gas equipment based on the effective pressure values obtained daily;

[0042] S3. Calculate the annual leakage rate based on the gas leakage amount, gas leakage rate, and leakage growth rate. Compare the annual leakage rate with the preset standard annual leakage rate. If the annual leakage rate exceeds the standard annual leakage rate, mark the SF6 gas equipment and include it in the early warning library;

[0043] S4. Draw a gas pressure trend chart of the SF6 gas equipment for the SF6 gas equipment marked in the early warning library based on the daily updated pressure values combined with the gas leakage amount, leakage rate, and leakage growth rate;

[0044] S5. Predict the gas replenishment alarm time of the SF6 gas equipment based on the gas pressure trend chart of the SF6 gas equipment marked in the early warning library;

[0045] S6. Determine the optimal gas replenishment time based on the gas replenishment alarm time of the SF6 gas equipment, and determine the number of SF6 gas equipment to be replenished within the optimal gas replenishment time;

[0046] S7. When the number of SF6 gas equipment to be replenished reaches the set value, perform centralized gas replenishment operations.

[0047] By determining the effective pressure value of the SF6 gas equipment daily, calculating the gas leakage amount, gas leakage rate, and leakage growth rate of the SF6 gas equipment to draw a gas pressure trend chart, it can be predicted when the equipment will trigger a system alarm based on the gas pressure trend chart, and the optimal gas replenishment time is determined as 3 months before the system alarm trigger time. When the replenishment quantity reaches the set quantity for the optimal gas replenishment time, centralized gas replenishment can be carried out, reducing the attendance of personnel and vehicles and avoiding the load loss caused by the sudden stop of the equipment.

[0048] The following further elaborates on the technical solution of the present invention in conjunction with the attached Figures 1 - 3 , and further explains the technical solution of the present invention:

[0049] Example 1

[0050] As Figure 1As shown in the figure, the present application discloses an on-line prediction system for SF6 gas equipment leakage in a substation, which includes a number of SF6 gas monitoring terminals. Each of the SF6 gas monitoring terminals is respectively and correspondingly installed on a number of SF6 circuit breakers. The SF6 gas monitoring terminals are respectively provided with a first detection component for monitoring the external environmental temperature and a second detection component for monitoring the SF6 gas temperature. The SF6 gas monitoring terminals are communicatively connected to a mobile terminal through a 4G short message alarm module, and the SF6 gas monitoring terminals are communicatively connected to a remote control host. That is to say, SF6 gas monitoring terminals are respectively configured on multiple SF6 gas equipment in the substation. The first detection component and the second detection component on the SF6 gas monitoring terminals are used to monitor the external environmental temperature and the SF6 gas temperature respectively. The effective pressure value of the SF6 gas obtained by the SF6 gas monitoring terminal is determined according to the difference between the external environmental temperature and the SF6 gas temperature. And the annual leakage rate is calculated according to the effective pressure value obtained daily. When the annual leakage rate exceeds the standard annual leakage rate, the SF6 gas monitoring terminal sends an alarm message to the mobile terminal through the 4G short message alarm module, and the staff can perform gas replenishment operations in time according to the alarm message.

[0051] The SF6 gas monitoring terminal includes an SF6 density meter 1 and a connection component. The lower part of the SF6 density meter 1 is communicated with the connection component and the lower part of the SF6 density meter 1 is communicated with the connection component; a control component is arranged on the connection component. The first detection component and the second detection component are respectively arranged on the connection component. The first detection component and the second detection component are both electrically connected to the control component. The control component is communicatively connected to the mobile terminal through a 4G short message alarm module, and the control component is communicatively connected to the remote control host through an RS485 communication bus. That is to say, the SF6 density meter is used to monitor the gas pressure change of the SF6 gas equipment in real time. The pressure data obtained by the SF6 and the temperature data obtained by the first detection component and the second detection component are transmitted to the control component in real time. The control component transmits all the data to the remote control host through the communication network in real time, which is convenient for the staff in the monitoring center to understand the state change parameters of the SF6 gas equipment in real time. It should be noted that the pressure value on the popular density meter or density relay that is not in use is replaced by using the pressure gauge of an ordinary meter to obtain the pressure value, and the pressure value and temperature value of the ordinary pressure gauge are read in real time. The accurate density pressure value is calculated according to the FS6 gas temperature-pressure relationship table. In this way, both early warning and prediction can be realized, and false alarms caused by the problems of temperature compensation lag and overcompensation can be avoided. The data collected from all the gas equipment on site are directly input into the background computer, and the prediction calculation is directly carried out in the computer program. The empirical formula commonly used for the state parameters of sulfur hexafluoride is used in the program to directly perform the above device functions.

[0052] A first adjusting member 5 for controlling the introduction of SF6 gas into the SF6 density gauge and a second adjusting member 6 for controlling the evacuation of SF6 gas in the SF6 density gauge are provided on the connection assembly. The first adjusting member 5 and the second adjusting member 6 are both electrically connected to the control assembly. That is to say, the first adjusting member is used to control the introduction of SF6 gas in the SF6 gas equipment into the SF6 density gauge, and the second adjusting assembly can be used for regular exhaust treatment during the subsequent daily maintenance of the SF6 density gauge.

[0053] The connection assembly includes a connecting pipe 2. A first connection base 11 is provided at the lower part of the SF6 density gauge 1, and a second connection base 21 is provided at the upper part of the connecting pipe 2. The first connection base 11 and the second connection base 21 are detachably connected, and the SF6 density gauge 1 is in communication with the connecting pipe 2. The control assembly, the first detection assembly, the second detection assembly, the first adjusting member and the second adjusting member are respectively arranged on the connecting pipe 2. That is to say, the first connection base and the second connection base are detachably connected by bolts, and a sealing ring is provided between the first connection base and the second connection base. Once the SF6 density gauge or the connecting pipe is damaged, the SF6 density gauge or the connecting pipe can be directly disassembled and replaced.

[0054] The first detection assembly is arranged inside the connecting pipe 2, the second detection assembly is arranged outside the connecting pipe 2. A connection head 4 is arranged on one side of the connecting pipe. An air inlet is provided on the connection head 4, and the first adjusting member 5 is arranged in the air inlet. An exhaust port is provided at the lower part of the connecting pipe 1, and the second adjusting member 6 is arranged in the exhaust port. That is to say, the air inlet and the exhaust port are vertically and crosswise distributed. On the one hand, it is convenient for the connecting pipe to be butt-connected and installed on the SF6 gas equipment. On the other hand, it is convenient for the subsequent rapid exhaust treatment of the SF6 density gauge.

[0055] The first detection assembly includes a first temperature sensor, the second detection assembly includes a second temperature sensor, the first adjusting member includes a first solenoid valve, the second adjusting member includes a second solenoid valve, the control assembly includes a control panel 3, and the control panel 3 is arranged outside the connecting pipe 2. The control panel 3 is electrically connected to the first temperature sensor, the second temperature sensor, the first solenoid valve and the second solenoid valve respectively. That is to say, the first temperature sensor and the second temperature sensor are used to detect the external environmental temperature and the SF6 gas temperature respectively. According to the external temperature and the SF6 gas temperature, it is helpful to determine the effective pressure value of the day. By controlling the opening of the first solenoid valve, the SF6 gas in the SF6 gas equipment can be controlled to be introduced into the SF6 density gauge. Closing the first solenoid valve and opening the second solenoid valve can evacuate the SF6 gas in the SF6 density gauge.

[0056] An LCD display screen is provided on the control panel 3. A storage battery and a DSP signal processor are provided inside the control panel 3. The DSP signal processor is electrically connected to the first temperature sensor, the second temperature sensor, the first electromagnetic valve, and the second electromagnetic valve respectively. The DSP signal processor is electrically connected to the SF6 density meter through an A / D signal converter. The DSP signal processor is communicatively connected to the mobile terminal through a 4G SMS warning module. The DSP signal processor is communicatively connected to the remote control host through an RS485 communication bus. That is to say, the pressure parameters obtained by the first temperature sensor, the second temperature sensor, and the SF6 density meter are displayed on the LCD display screen in real time, and the DSP signal processor can transmit various data to the remote control host in real time for the staff to understand the state change of the SF6 gas equipment in real time.

[0057] Embodiment 2

[0058] As Figure 2 and Figure 3 shown, the present application discloses an online prediction method for leakage of SF6 gas equipment in a substation, including the following steps:

[0059] S1. Obtain the effective pressure value of the SF6 gas equipment on the current day. Use the first temperature sensor and the second temperature sensor to obtain the external environment temperature and the SF6 gas temperature in real time. If the temperature difference between the external environment and the SF6 gas is within the normal threshold range, the pressure value obtained by the SF6 density meter is the effective value on the current day. If the temperature difference between the external environment and the SF6 gas exceeds the normal threshold range, compare the SF6 gas temperatures monitored at two time points in the early morning of the same day. If the temperature difference between the SF6 gas temperatures monitored at the two time points is less than the set threshold, then select the pressure data monitored by the SF6 density meter at the later time point as the effective pressure value on the current day. If the temperature difference between the SF6 gas temperatures monitored at the two time points exceeds the set threshold, then select the effective pressure value of the previous day as the effective pressure value on the current day. That is to say, when collecting the SF6 gas temperatures at two time points in the early morning of the same day, taking 5 am and 2 am as an example, collect the pressure value at 5 am, the temperature value at 5 am, and the temperature value at 2 am. In the first step, compare the temperature values at 5 am and 2 am. If the difference is less than 2 degrees, the pressure value at 5 am is used as the data for the current day. If the difference is greater than 2 degrees, the pressure value at 5 am is not used as the data for the current day (which can avoid the pressure values collected during cold snaps or thunderstorm weather in the early morning), and the pressure value of the previous day is used as the data for the current day. The reason for extracting data in the early morning is that the density meter (which is already popular) has temperature compensation. The temperature compensation principle is: when the temperature is stable, whether it is 0 degrees or 40 degrees, the pressure gauge always shows the pressure value at 20 degrees. When the temperature changes, the change in pressure lags, and the obtained pressure value is inaccurate. However, the equipment load is stable in the early morning, the temperature is low and stable, and the temperature compensation is also stable, so the measured pressure value is stable and accurate.

[0060] S2. According to the effective pressure value obtained daily, calculate the gas leakage amount, gas leakage rate, and leakage growth rate of the SF6 gas equipment. The gas leakage amount includes the annual gas leakage amount, monthly gas leakage amount, and weekly gas leakage amount. The gas leakage rate includes the annual gas leakage rate, monthly gas leakage rate, and weekly gas leakage rate. The leakage growth rate includes the annual leakage growth rate, monthly gas leakage growth rate, and weekly gas leakage growth rate.

[0061] S3. Calculate the annual leakage rate based on the gas leakage amount, gas leakage rate, and leakage growth rate. Compare the annual leakage rate with the preset standard annual leakage rate. If the annual leakage rate exceeds the standard annual leakage rate, mark the SF6 gas equipment and include it in the early warning library. According to the values extracted daily, calculate the gas leakage amount, leakage rate, and leakage growth rate of the gas equipment (annual, monthly, weekly). Convert the obtained data into the annual leakage rate, and compare it with the specified annual leakage rate standard (the national standard is 5‰). Include the equipment with an annual leakage rate exceeding the standard in the early warning library.

[0062] S4. For the SF6 gas equipment marked in the early warning library, a gas pressure trend chart of the SF6 gas equipment is drawn based on the daily updated pressure value in combination with the gas leakage volume, leakage rate, and leakage growth rate. For the equipment in the early warning library, a gas pressure trend chart is drawn based on the daily updated pressure value in combination with the (annual, monthly, weekly) gas leakage volume, leakage rate, and leakage growth rate.

[0063] S5. Predict the air replenishment alarm time of the SF6 gas equipment according to the gas pressure trend chart of the SF6 gas equipment marked in the early warning library.

[0064] S6. Determine the optimal air replenishment time according to the air replenishment alarm time of the SF6 gas equipment. Determine the number of SF6 gas equipment to be replenished according to the optimal air replenishment time, and predict when the equipment will trigger the system alarm value. The optimal air replenishment timing is 3 months before the system alarm value is triggered, to avoid false alarms caused by large short-term temperature differences and long temperature compensation response times (temperature compensation has a lag in displaying real values and overcompensation problems) in winter and summer.

[0065] S7. When the number of SF6 gas equipment to be replenished reaches the set value, centralized air replenishment operations are carried out. As the number of equipment in the early warning library increases, according to the early warning prediction, it is possible to avoid air replenishment in bad weather, reduce potential safety hazards, and also be able to deploy in advance and conduct centralized air replenishment according to the optimal air replenishment timing, improving work efficiency.

[0066] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed.

Claims

1. An on-line prediction method for SF6 gas equipment leakage in a substation, characterized in that, Including the steps: S1. Obtain the effective pressure value of the SF6 gas equipment on the current day; S2. Calculate the gas leakage amount, gas leakage rate, and leakage growth rate of the SF6 gas equipment based on the effective pressure values obtained daily; S3. Calculate the annual leakage rate based on the gas leakage amount, gas leakage rate, and leakage growth rate. Compare the annual leakage rate with the preset standard annual leakage rate. If the annual leakage rate exceeds the standard annual leakage rate, mark the SF6 gas equipment and include it in the early warning library; S4. Draw a gas pressure trend chart of the SF6 gas equipment for the marked SF6 gas equipment in the early warning library based on the daily updated pressure values combined with the gas leakage amount, leakage rate, and leakage growth rate; S5. Predict the gas replenishment alarm time for the SF6 gas equipment based on the gas pressure trend chart of the marked SF6 gas equipment in the early warning library; S6. Determine the optimal gas replenishment time based on the gas replenishment alarm time of the SF6 gas equipment, and determine the number of SF6 gas equipment to be replenished within the optimal gas replenishment time; S7. When the number of SF6 gas equipment to be replenished reaches the set value, perform centralized gas replenishment operations; The method for obtaining the effective pressure value of the SF6 gas equipment on the current day in step S1 includes the following steps: S11. Obtain the external environmental temperature and the SF6 gas temperature; S12. If the temperature difference between the external environment and the SF6 gas is within the normal threshold range, the pressure value obtained by the SF6 density table is the effective value on the current day; S13. If the temperature difference between the external environment and the SF6 gas exceeds the normal threshold range, compare the SF6 gas temperatures monitored at two time points in the early morning of the current day; S14. If the temperature difference between the SF6 gas temperatures monitored at the two time points is less than the set threshold, select the pressure data monitored by the SF6 density table at the later time point as the effective pressure value on the current day; if the temperature difference between the SF6 gas temperatures monitored at the two time points exceeds the set threshold, select the effective pressure value of the previous day as the effective pressure value on the current day.

2. The on-line prediction method for SF6 gas equipment leakage in a substation according to claim 1, characterized in that, The gas leakage amount in step S2 includes the annual gas leakage amount, monthly gas leakage amount, and weekly gas leakage amount. The gas leakage rate in step S2 includes the annual gas leakage rate, monthly gas leakage rate, and weekly gas leakage rate. The leakage growth rate in step S2 includes the annual leakage growth rate, monthly gas leakage growth rate, and weekly gas leakage growth rate.

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