SF6 gas on-line monitoring and supplementing system

Abstract

The invention provides an SF6 gas on-line monitoring and supplementing system in the GIS field. Comprising a system host, a terminal, a pressure sensor, a density relay, an SF6 gas analyzer, an SF6 gas density meter, an SF6 gas density relay and an SF6 gas leak detector. When the pressure sensor detects that the pressure of the SF6 gas is lower than a specified value, an SF6 gas cylinder of an SF6 external gas source of the system is started to supplement the SF6 gas; and the density relay monitors the micro water volume in the GIS equipment. The device is externally connected with an SF6 gas analyzer to analyze whether the SF6 gas in the SF6 gas cylinder and the GIS is qualified or not; the SF6 gas leak detector transmits the leakage condition to the system host; the system host is connected with the monitoring device, monitored SF6 gas pressure data are transmitted to the background terminal in real time through the gateway, and pressure value real-time previewing and warning signal real-time pushing are achieved. The system is suitable for being used as an SF6 gas on-line monitoring and supplementing system.

Description

Technical Field

[0001] The present invention provides an arc extinguishing medium for a sulfur hexafluoride gas-insulated fully enclosed power distribution device, specifically, an SF6 gas online monitoring and replenishing system. Background Art

[0002] At present, the rapid development of the power industry has led to the widespread application of various intelligent devices in power and electrical equipment to maintain the operating status of various power and electrical equipment. Sulfur hexafluoride gas insulated fully enclosed distribution device, referred to as GIS. It consists of circuit breakers, disconnectors, grounding switches, transformers, lightning arresters, busbars, connectors and outgoing line terminals. These devices or components are all enclosed in a metal grounded casing, which is filled with SF6 insulating gas at a certain pressure. High-voltage electrical equipment with high operating reliability, low maintenance workload and long maintenance cycle has a failure rate of only 20%~40% of conventional equipment.

[0003] However, GIS also has its inherent disadvantages. Due to the influence of factors such as SF6 gas leakage, external moisture infiltration, the presence of conductive impurities, and insulator aging, GIS internal flashover failures may occur. The fully sealed structure of GIS makes it difficult to locate and repair faults. The maintenance work is complicated. The average power outage maintenance time after an accident is longer than that of conventional equipment. The power outage range is large and often involves many non-faulty components.

[0004] GIS electrical equipment has received extensive attention in the operation of power electrical equipment due to its large capacity, multiple operation times, safe and stable operation, etc. During the operation of GIS electrical equipment, since the equipment is in operation for a long time, it is necessary to provide it with the required SF6 gas through other equipment. When SF6 gas is filled into the equipment, in order to ensure safety, the operating environment requirements are relatively high, and the gas may contain moisture. The price of SF6 gas is very high, and once it leaks, it will cause serious environmental pollution. Summary of the invention

[0005] In order to solve the deficiencies in the prior art and address the many disadvantages of traditional gas replenishment methods, the present invention proposes an SF6 gas online monitoring and replenishment system. The system uses pressure sensors and density relays to accurately monitor the internal SF6 gas pressure of GIS equipment, and is connected to an SF6 gas analyzer and SF6 gas leak detector. The system host transmits the monitored SF6 gas pressure data to the backend terminal through a gateway in real time, achieving real-time preview of the pressure value and real-time push of alarm signals, solving the technical problems of SF6 gas online monitoring and replenishment.

[0006] The solution adopted by the present invention to solve the technical problem is: The SF6 gas online monitoring and replenishment system includes a system host, terminal, pressure sensor, density relay, SF6 gas analyzer, SF6 gas density meter, SF6 gas density relay and SF6 gas leak detector; The pressure sensor is used to accurately test the SF6 gas pressure in the GIS equipment and transmit it to the system host. It has a monitoring function. When it detects that the SF6 gas pressure is lower than the specified value, the system's SF6 external gas source SF6 gas cylinder is started to replenish SF6 gas; Density relay is used to monitor SF6 gas in GIS equipment. It has three key states: "normal", "alarm" and "lockout". It monitors the amount of water inside the GIS equipment and has the functions of control and protection. SF6 gas analyzer, used to measure the humidity, percentage concentration and main decomposition products of SF6 gas, analyze whether the quality of SF6 gas in SF6 gas cylinder and GIS is qualified, and ensure the electrical performance of GIS equipment; SF6 gas leak detector: SF6 gas leak detection devices are placed at key locations and the leakage status is transmitted to the system host; The system host collects data information from density relays and pressure sensors, and communicates data with desktop terminals and mobile terminals through gateways; The gateway runs at the top layer of the OSI7 layer protocol - the application layer. It plays the important role of conversion. Between two systems that use different communication protocols, data formats or languages, or even completely different architectures, the gateway repackages the received information to meet the needs of the destination system. At the same time, it provides filtering and security functions. The terminals include desktop terminals and mobile terminals, which monitor the SF6 gas pressure inside the GIS equipment, SF6 gas quality analysis, SF6 gas leakage, the current status of the density relay and the real-time on-site images of the monitored equipment in real time.

[0007] Positive effect, because the present invention uses pressure sensor and density relay to accurately monitor the internal SF6 gas pressure of GIS equipment, and at the same time connects to SF6 gas analyzer to analyze whether the quality of SF6 gas cylinder and SF6 gas inside GIS is qualified; SF6 gas leak detector is arranged at key position, and the leakage status is transmitted to the system host; the system host directly connects the system with the monitoring equipment, and transmits the monitored SF6 gas pressure data to the background terminal through the gateway in real time, so as to realize the real-time preview of pressure value and the real-time push of alarm signal. It is suitable for application as SF6 gas online monitoring and replenishment system. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a structural block diagram of this embodiment. DETAILED DESCRIPTION

[0009] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0010] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0011] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0012] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0013] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0014] In the present invention, all embodiments, implementations and features of the present invention can be combined with each other without contradiction or conflict. In the present invention, conventional equipment, devices, components, etc. can be purchased commercially or made according to the contents disclosed in the present invention. In the present invention, in order to highlight the key points of the present invention, some conventional operations and equipment, devices, components are omitted or only briefly described.

[0015] As shown in the figure, the SF6 gas online monitoring and replenishment system includes a system host, a terminal, a pressure sensor, a density relay, a SF6 gas analyzer, a SF6 gas density meter, a SF6 gas density relay and a SF6 gas leak detector; The pressure sensor is used to accurately test the SF6 gas pressure in the GIS equipment and transmit it to the system host. It has a monitoring function. When it detects that the SF6 gas pressure is lower than the specified value, the system's SF6 external gas source SF6 gas cylinder is started to replenish SF6 gas; Density relay is used to monitor SF6 gas in GIS equipment. It has three key states: "normal", "alarm" and "lockout". It monitors the amount of water inside the GIS equipment and has the functions of control and protection. SF6 gas analyzer, used to measure the humidity, percentage concentration and main decomposition products of SF6 gas, analyze whether the quality of SF6 gas in SF6 gas cylinder and GIS is qualified, and ensure the electrical performance of GIS equipment; SF6 gas leak detector: SF6 gas leak detection device is arranged at key positions, and the leakage status is transmitted to the system host; in this embodiment, the SF6 gas leak detector adopts SF6 gas infrared imaging leak detector; The system host collects data information from density relays and pressure sensors, and communicates data with desktop terminals and mobile terminals through gateways; The gateway runs at the top layer of the OSI7 layer protocol - the application layer. It plays the important role of conversion. Between two systems that use different communication protocols, data formats or languages, or even completely different architectures, the gateway repackages the received information to meet the needs of the destination system. At the same time, it provides filtering and security functions. The terminals include desktop terminals and mobile terminals, which monitor the SF6 gas pressure inside the GIS equipment, SF6 gas quality analysis, SF6 gas leakage, the current state of the density relay and the real-time on-site images of the monitored equipment in real time; The working principle of this embodiment: The pressure sensor and density relay monitor the internal SF6 gas pressure of the GIS equipment accurately, and are connected to an external SF6 gas analyzer to analyze whether the quality of the SF6 gas cylinder and the SF6 gas inside the GIS is qualified; SF6 gas leak detectors are arranged at key locations, and the leakage status is transmitted to the system host; the system host is designed with anti-misoperation logic judgment to avoid man-made safety hazards, while reducing the number and workload of staff required for gas replenishment; the system is directly connected to the monitoring equipment, and the monitored SF6 gas pressure data is transmitted to the background terminal, mobile phone App, etc. through the gateway in real time, realizing real-time preview of pressure values ​​and real-time push of alarm signals.

[0016] Working process of the present invention: The gas replenishment process of this system mainly includes: gas line cleaning → gas replenishment start → gas replenishment process → gas replenishment completion, a total of four stages; In the gas path cleaning stage, the gas path is cleaned according to the gas path direction, SF6 gas cylinder → flow controller → pressure sensor → gas recovery unit; When the gas replenishment starts, the gas circuit and gas chamber pressure are monitored according to the set target pressure, gas circuit flow rate, interval time and other parameter information. At the same time, the gas flow rate is automatically adjusted according to the settings, and the gas is replenished according to the direction of the gas circuit, SF6 gas cylinder → flow controller → pressure sensor → SF6 switch gas chamber; Record the pressure difference between the measured pressure and the target pressure during the initial gas replenishment, the target pressure minus the pressure before gas replenishment, initialize the flow rate of the gas flow meter, and start gas replenishment; During the gas replenishment process, the system will close the gas cylinder after a period of gas replenishment and measure the internal pressure of the GIS equipment at this time. According to the percentage of remaining gas replenishment at this time: (target pressure-real-time pressure) / (target pressure-pressure before gas replenishment), the single gas replenishment volume, gas replenishment duration, and gas flow rate are controlled according to this ratio; Stop the gas replenishment operation, close the SF6 gas cylinder to end the gas replenishment process, and record the gas replenishment data. Monitor the electrical performance of this GIS equipment based on the amount and frequency of gas replenishment.

[0017] Online monitoring process: In order to ensure the stable operation of the system, the system and the GIS equipment to be supplied with gas need to be monitored online in real time during operation. SF6 gas leakage detection devices are installed at key locations on GIS equipment to monitor the tightness of the equipment; SF6 gas analyzers are installed on GIS equipment and SF6 gas cylinders; SF6 gas pressure of substation field equipment is monitored in real time, and the SF6 gas pressure change curve is drawn based on the measured values. This part transmits various monitored data to the terminal in real time, realizing real-time preview of pressure values ​​and real-time push of alarm signals.

[0018] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. SF6 gas online monitoring and replenishment system, its characteristics are: Including system host, terminal, pressure sensor, density relay, SF6 gas analyzer, SF6 gas density meter, SF6 gas density relay and SF6 gas leak detector; The pressure sensor is used to accurately test the SF6 gas pressure in the GIS equipment and transmit it to the system host. It has a monitoring function. When it detects that the SF6 gas pressure is lower than the specified value, the system's SF6 external gas source SF6 gas cylinder is started to replenish SF6 gas; The density relay is used to monitor the SF6 gas in GIS equipment. It has three key states: "normal", "alarm" and "locked". It monitors the amount of water inside the GIS equipment and has the functions of control and protection. The SF6 gas analyzer is used to measure the humidity, percentage concentration and main decomposition products of SF6 gas, analyze whether the quality of SF6 gas in SF6 gas cylinder and GIS is qualified, and ensure the electrical performance of GIS equipment; The SF6 gas leak detector is arranged at a key position and transmits the leakage status to the system host; The system host collects data information from density relays and pressure sensors, and communicates data with desktop terminals and mobile terminals through gateways; The gateway runs at the top layer of OSI7 protocol - the application layer, and plays the important role of conversion. Between two systems using different communication protocols, data formats or languages, or even completely different architectures, the gateway repackages the received information to meet the needs of the destination system; at the same time, it provides filtering and security functions; The terminals include desktop terminals and mobile terminals, which monitor the SF6 gas pressure inside the GIS equipment, the SF6 gas quality analysis, the SF6 gas leakage, the current state of the density relay and the real-time on-site images of the monitored equipment in real time.

2. The SF6 gas online monitoring and replenishment system according to claim 1 is characterized in that: The SF6 gas leak detector uses SF6 gas infrared imaging leak detector.

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