High-precision handheld SF6 gas density detection device, and detection method

Abstract

Provided are a high-precision handheld SF6 gas density detection device (10), and a detection method. The high-precision handheld SF6 gas density detection device (10) comprises a gas path connector (20), a measurement mechanism (30) and a handheld mechanism (40); the gas path connector (20) is used for connecting to an SF6 gas chamber of an electrical device under test, and one end of the gas path connector (20) is provided with a plurality of different types of adapters; the measurement mechanism (30) is used for acquiring temperature information and pressure information of the SF6 gas chamber, and the measurement mechanism (30) is electrically connected to the handheld mechanism (40) so as to transmit the temperature information and pressure information of the SF6 gas chamber to the handheld mechanism (40); the measurement mechanism (30) comprises a first temperature sensor (301) and a pressure sensor (302), the first temperature sensor (301) and the pressure sensor (302) being electrically connected to the handheld mechanism (40); the handheld mechanism (40) is used for storing the temperature information and pressure information acquired by the measurement mechanism (30), and, according to the temperature information and the pressure information, calculating a corresponding density, so as to determine whether a leakage has occurred in the SF6 gas chamber; the handheld mechanism (40) comprises a reinforced housing (401), a controller (402), a memory (403), a timer (404) and a power supply.

Description

High-precision handheld SF6 gas density detection device and detection method Technical Field

[0001] This invention relates to the field of gas density detection technology, and in particular to a high-precision handheld SF6 gas density detection device and detection method. Background Technology

[0002] In the power industry, SF6 gas, with its superior insulation and arc-extinguishing properties, has become an indispensable key insulating gas in high-voltage electrical equipment, widely used in core electrical equipment such as circuit breakers, transformers, and gas-insulated switches. The density state of SF6 gas is closely related to its electrical performance and the operational safety of the equipment. Traditionally, the monitoring of SF6 gas density mainly relies on density relays or transmitters installed on electrical equipment. These instruments can track changes in SF6 gas density in real time, providing strong support for the stable operation of the power system. However, instruments operating over long periods are susceptible to various factors such as aging, environmental pollution, or calibration deviations, leading to a gradual decrease in measurement accuracy, which in turn affects the safety and reliability of the equipment.

[0003] To verify the accuracy of key data from field instruments, the traditional testing methods are as follows:

[0004] First, the instruments are removed from the operating equipment and sent to a professional laboratory for testing. This process is not only time-consuming and inefficient, severely affecting the continuous operation of the equipment, but also increases the complexity of operation and maintenance costs.

[0005] Second, on-site testing can be conducted using professional testing instruments. These instruments are generally expensive, bulky, complex to operate, and subject to limited conditions. They also require certain skills from the operators and are greatly affected by environmental factors, making it difficult to guarantee the accuracy and efficiency of the testing.

[0006] In practical field applications, when a gas density relay alarms or its displayed value is too low, people often simply add gas to the electrical equipment. However, the problem is often with the density relay itself, not a leak in the electrical equipment. This leads to the relay being overfilled, eventually causing the safety valve to release and resulting in a serious quality incident. Summary of the Invention

[0007] Therefore, it is necessary to provide a high-precision handheld SF6 gas density detection device that is efficient, accurate, portable, and easy to operate.

[0008] It is also necessary to provide a method for detecting the density of SF6 gas.

[0009] A high-precision handheld SF6 gas density detection device includes a gas circuit interface, a detection mechanism, and a handheld mechanism;

[0010] The gas interface is used to connect to the SF6 gas chamber of the electrical equipment under test. One end of the gas interface is equipped with multiple different types of adapters to adapt to the SF6 gas chambers of different electrical equipment under test. During operation, one end of the gas interface is connected to the SF6 gas chamber of the electrical equipment under test, and the other end of the gas interface is connected to the testing mechanism.

[0011] The detection mechanism is used to collect temperature and pressure information of the SF6 gas chamber. The detection mechanism is electrically connected to the handheld mechanism to transmit the temperature and pressure information of the SF6 gas chamber to the handheld mechanism. The detection mechanism includes a first temperature sensor and a pressure sensor, which are electrically connected to the handheld mechanism.

[0012] The handheld mechanism stores the temperature and pressure information collected by the detection mechanism, and calculates the corresponding density based on the temperature and pressure information to determine whether there is an abnormality in the SF6 gas chamber. The handheld mechanism includes a reinforced shell, a controller, a memory, a timer, and a power supply. The controller, memory, timer, and power supply are housed in the reinforced shell. The controller is electrically connected to a pressure sensor and a first temperature sensor to convert the temperature and pressure information collected by the pressure sensor and the first temperature sensor into temperature detection values ​​and pressure detection values, respectively. The controller is also electrically connected to the memory to store the temperature and pressure detection values. The memory also stores pressure thresholds corresponding to different temperatures. The controller retrieves the corresponding pressure threshold at the same temperature from the memory based on the temperature detection value to determine whether the pressure detection value is abnormal. If the pressure detection value is less than or equal to the pressure threshold, then the pressure detection value is abnormal. The controller is also electrically connected to the timer to count the duration of temperature detection and pressure detection. The controller also stores the location information, ID information, and time information of the measurement point in the memory to facilitate data analysis by personnel. The power supply provides power to the handheld mechanism.

[0013] A method for detecting SF6 gas density includes the following steps:

[0014] Step S1: Use a handheld high-precision SF6 gas density detector to measure the temperature and pressure of the SF6 gas chamber of the electrical equipment under test;

[0015] Step S2: Find the corresponding pressure threshold based on the detected temperature. If the detected pressure is less than or equal to the pressure threshold, then an SF6 gas leakage anomaly has occurred at the detection point; if the detected pressure is greater than the pressure threshold, there is no SF6 gas leakage.

[0016] Step S3: When an SF6 gas leak is abnormal, the gas path information analysis module issues an alarm voice and displays the current temperature, pressure and gas density values.

[0017] Beneficial Effects: The high-precision handheld SF6 gas density detector of this invention adopts a split design. The detection mechanism is directly connected to the gas supply line of the electrical equipment under test via a conversion connector. Data is transmitted to the handheld mechanism through the gas line interface, avoiding excessively long external gas lines and reducing the possibility of gas leakage. The variety of conversion connectors allows for compatibility with electrical equipment from different manufacturers or models. The split design facilitates disassembly and can be packed into a customized toolbox, making it more convenient for maintenance personnel to travel long distances. In case of failure of the detection mechanism or handheld mechanism, the split design allows for flexible replacement of the faulty mechanism, providing redundancy. For batch measurements, the detector can store data. Each measurement data entry includes user-input information such as the location of the measurement point, ID information, temperature, pressure, density, and measurement time, facilitating data analysis. The detector is easy to assemble and carry, and simple to operate. Attached Figure Description

[0018] Figure 1 is a schematic diagram of the modules of the high-precision handheld SF6 gas density detection device of the present invention.

[0019] Figure 2 is a schematic diagram of the handheld mechanism of the present invention.

[0020] Figure 3 is a schematic diagram of the interaction principle of the present invention.

[0021] The figure shows: a high-precision handheld SF6 gas density detection device 10, a gas path interface 20, a detection mechanism 30, a first temperature sensor 301, a pressure sensor 302, a handheld mechanism 40, a reinforced shell 401, a controller 402, a memory 403, a timer 404, and a display 405. Detailed Implementation

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Please refer to Figures 1 and 2. The high-precision handheld SF6 gas density detection device 10 includes a gas interface 20, a detection mechanism 30, and a handheld mechanism 40.

[0024] The gas interface 20 is used to connect to the SF6 gas chamber of the electrical equipment under test. One end of the gas interface 20 is provided with multiple different types of adapters to adapt to the SF6 gas chambers of different electrical equipment under test. During operation, one end of the gas interface 20 is connected to the SF6 gas chamber of the electrical equipment under test, and the other end of the gas interface 20 is connected to the testing mechanism 30.

[0025] The detection mechanism 30 is used to collect temperature and pressure information of the SF6 gas chamber. The detection mechanism 30 is electrically connected to the handheld mechanism 40 to transmit the temperature and pressure information of the SF6 gas chamber to the handheld mechanism 40. The detection mechanism 30 includes a first temperature sensor 301 and a pressure sensor 302, which are electrically connected to the handheld mechanism 40.

[0026] The handheld mechanism 40 is used to store the temperature and pressure information collected by the detection mechanism 30, and calculate the corresponding density based on the temperature and pressure information to determine whether there is an abnormality in the SF6 gas chamber. The handheld mechanism 40 includes a reinforced shell 401, a controller 402, a memory 403, a timer 404, and a power supply. The controller 402, memory 403, timer 404, and power supply are disposed in the reinforced shell 401. The controller 402 is electrically connected to the pressure sensor 302 and the first temperature sensor 301 to convert the temperature and pressure information collected by the pressure sensor 302 and the first temperature sensor 301 into temperature detection values ​​and pressure detection values. The controller 402 is also connected to... The memory 403 is electrically connected to store temperature and pressure detection values. The memory 403 also stores pressure thresholds corresponding to different temperatures. The controller 402 retrieves the corresponding pressure threshold at the same temperature from the memory 403 based on the temperature detection value to determine if the pressure detection value is abnormal. If the pressure detection value is less than or equal to the pressure threshold, then the pressure detection value is abnormal. The controller 402 is also electrically connected to the timer 404 to count the duration of temperature and pressure detection. The controller 402 also stores the location information, ID information, and time information of the measurement point in the memory 403 to facilitate data analysis by personnel. The power supply is used to power the handheld mechanism 40.

[0027] Furthermore, the handheld mechanism 40 also includes a display 405. In a preferred embodiment, the display 405 is an integrated resistive touchscreen, which not only has strong anti-electromagnetic interference capabilities, but also provides users with a quick and simple interaction method and rich interactive functions.

[0028] In a preferred embodiment, if the display 405 is not touched within 60 seconds, the system enters a low-power mode and is woken up by being touched again.

[0029] Specifically, the "pressure threshold corresponding to the same temperature in memory 403" is obtained by conducting temperature and pressure tests on SF6 to obtain the SF6 liquefaction temperature at different pressures and the liquefaction pressure drop value at different temperatures. This pressure drop value is the pressure threshold. Based on the detected temperature, the pressure drop value at that temperature, i.e., the pressure threshold, is retrieved. If the detected pressure value is less than or equal to the pressure threshold, then the controller 402 issues a liquefaction warning signal and / or information, which is displayed on the display 405.

[0030] Furthermore, the detection mechanism 30 also includes a second temperature sensor to diagnose the performance of the gas density relay on the electrical equipment. The second temperature sensor is located outside the detection mechanism 30 and can extend into the housing of the gas density relay. The second temperature sensor is electrically connected to the controller 402. The controller 402 receives the detection pressure and detection temperature from the pressure sensor 302 and the second temperature sensor to obtain the detection density value. Then, it compares the detection density value with the density value on the gas density relay to determine whether the gas density relay is working properly.

[0031] In a preferred embodiment, the high-precision handheld SF6 gas density detection device further includes a power diagnostic module, which is electrically connected to the handheld mechanism 40 and displays the power level of the handheld mechanism 40.

[0032] The power diagnostic module includes:

[0033] A 24-bit high-speed analog-to-digital signal acquisition unit (ADC) U2 is used to acquire the voltage signal of a high-precision sampling resistor (R2);

[0034] A high-precision voltage reference chip (U1) is used to provide a reference voltage;

[0035] High-precision, low-temperature drift coefficient sampling resistor (0.01%, 25ppm / degree) to generate sampling voltage.

[0036] The voltage across the acquisition resistor (R2) connected in series with the battery is acquired by an analog-to-digital converter (U2), and the voltage (V) across the resistor and the current i during operation are calculated. The real-time battery charge is calculated by Q1 = i (real-time battery current) * t (time). Based on the real-time charge Q1 and the current discharge curve M in the battery specification, there is a certain mapping relationship between the real-time charge and the battery discharge curve, so the formula for the remaining battery charge is Q = f(Q1, M).

[0037] In a preferred embodiment, the air inlet 20 and the detection mechanism 30 are detachably connected.

[0038] When using it on site, first connect the gas interface 20 to the testing mechanism 30, keep the gas interface 20 open to the atmosphere, press the power switch, and after the handheld mechanism 40 system is initialized, select the appropriate adapter to connect to the SF6 gas chamber to be tested, and wait for the data to stabilize before reading the data information on the display 405 of the handheld mechanism 40.

[0039] In a preferred embodiment, referring to FIG3, the interaction flow of the handheld mechanism 40 of the present invention is as follows:

[0040] Press the power button to turn on the power. The monitor 405 displays page one: the welcome page, and then jumps to page two: the real-time display page of temperature, pressure and SF6 density. This page also provides the user with "menu" and "save" function buttons.

[0041] Clicking the "Save" button saves the current temperature, pressure, and SF6 density data from page two to memory 403. The user is then redirected to page three: the location information and ID number entry page. This page provides two clickable and inputtable text boxes for location information and ID information. Below the text boxes are displayed the temperature, pressure, and SF6 density data to be saved, as well as the time of the save operation. "Back to Previous Page" and "Save" buttons are also provided. Pressing the "Back to Previous Page" button redirects the user to page two; pressing the "Save" button saves the current data.

[0042] Clicking the location information text box will bring up a keyboard. Enter the location information consisting of English characters and numbers. Besides the English character and number keys, the keyboard uses "←" for backspace, "Esc" to close the keyboard, and "Enter" to confirm the input. The same applies to ID information input. After entering the location and ID information, click "Save," and you will be redirected to page four: the pop-up page. The pop-up page has "Confirm" and "Cancel" buttons. Pressing the "Confirm" button will store the entered location information, ID information, temperature, pressure, SF6 density data, and the time of the save operation as a single record in memory 403, and redirect you to page two. Pressing the "Cancel" button will directly redirect you to page two.

[0043] Press the "Menu" button on page 2 to jump to page 5. This page provides users with "Time Settings", "Brightness Configuration", "Shutdown Switch", and "Back to Previous Page" function buttons. Press "Back to Previous Page" to jump to page 2.

[0044] Pressing the "Time Configuration" button will navigate to page seven, which provides five clickable and inputtable text boxes corresponding to year, month, day, hour, minute, and second. Clicking a text box will bring up a keyboard, allowing the user to enter the year information in numbers. Except for the number keys, backspace key, and enter key, the rest of the keyboard is considered invalid; the same applies to day, hour, minute, and second. There is also a "Back to Previous Page" button; pressing this button will navigate to page five.

[0045] Press the "Brightness Configuration" button to go to page six. This page provides a graphical slider. Drag the slider to adjust the screen brightness. There is also a "Back" button. Press the "Back" button to go to page five.

[0046] Press the "Gas Pressure Switch" button to navigate to page eight, which provides "Gas Pressure" and "Absolute Pressure" buttons. Pressing the "Gas Pressure" button will display the relative pressure value in real time and automatically navigate to page five. Pressing the "Absolute Pressure" button will display the absolute pressure value in real time and automatically navigate to page five.

[0047] The method for detecting SF6 gas density of the present invention includes the following steps:

[0048] Step S1: Use a handheld high-precision SF6 gas density detector to measure the temperature and pressure of the SF6 gas chamber of the electrical equipment under test;

[0049] Step S2: Find the corresponding pressure threshold based on the detected temperature. If the detected pressure is less than or equal to the pressure threshold, then an SF6 gas leakage anomaly has occurred at the detection point; if the detected pressure is greater than the pressure threshold, there is no SF6 gas leakage.

[0050] Step S3: When an SF6 gas leak is abnormal, the gas path information analysis module issues an alarm voice and displays the current temperature, pressure and gas density values.

[0051] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the invention. Those skilled in the art will understand that implementing all or part of the above-described embodiments and making equivalent changes in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A high-precision handheld SF6 gas density detection device, characterized in that: Includes gas line interface, testing mechanism, and handheld mechanism; The gas interface is used to connect to the SF6 gas chamber of the electrical equipment under test. One end of the gas interface is equipped with multiple different types of adapters to adapt to the SF6 gas chambers of different electrical equipment under test. During operation, one end of the gas interface is connected to the SF6 gas chamber of the electrical equipment under test, and the other end of the gas interface is connected to the testing mechanism. The detection mechanism is used to collect temperature and pressure information of the SF6 gas chamber. The detection mechanism is electrically connected to the handheld mechanism to transmit the temperature and pressure information of the SF6 gas chamber to the handheld mechanism. The detection mechanism includes a first temperature sensor and a pressure sensor, which are electrically connected to the handheld mechanism. The handheld mechanism is used to store the temperature and pressure information collected by the detection mechanism, and calculate the corresponding density based on the temperature and pressure information to determine whether there is an abnormality in the SF6 gas chamber. The handheld mechanism includes a reinforced shell, a controller, a memory, a timer, and a power supply. The controller, memory, timer, and power supply are housed in the reinforced shell. The controller is electrically connected to the pressure sensor and the first temperature sensor to convert the temperature and pressure information collected by the pressure sensor and the first temperature sensor into temperature detection values ​​and pressure detection values. The controller is also electrically connected to the memory to store the temperature detection values ​​and pressure detection values. The memory also stores pressure thresholds corresponding to different temperatures. The controller retrieves the corresponding pressure threshold at the same temperature from the memory based on the temperature detection value to determine whether there is an abnormality in the pressure detection value. If the pressure reading is less than or equal to the pressure threshold, then the pressure reading is abnormal. The controller is also electrically connected to a timer to record the duration of temperature and pressure detection. The controller also stores the location, ID, and time information of the measurement points in the memory to facilitate data analysis. The power supply is used to power the handheld mechanism.

2. The high-precision handheld SF6 gas density detection device as described in claim 1, characterized in that: The handheld mechanism also includes a display, which is an integrated resistive touchscreen.

3. The high-precision handheld SF6 gas density detection device as described in claim 2, characterized in that: If the display is not touched for 60 seconds, the system enters a low-power mode and will wake up when touched again.

4. The high-precision handheld SF6 gas density detection device as described in claim 1, characterized in that: The testing mechanism also includes a second temperature sensor to diagnose the performance of the gas density relay on the electrical equipment; the second temperature sensor is located outside the testing mechanism and can extend into the housing of the gas density relay, and is electrically connected to the controller.

5. The high-precision handheld SF6 gas density detection device as described in claim 1, characterized in that: The high-precision handheld SF6 gas density detection device also includes a power diagnostic module, which is electrically connected to the handheld mechanism and displays the power level of the handheld mechanism. The power diagnostic module includes: A 24-bit high-speed analog-to-digital signal acquisition unit (ADC) U2 is used to acquire the voltage signal of a high-precision sampling resistor (R2); A high-precision voltage reference chip (U1) is used to provide a reference voltage; A high-precision, low-temperature drift coefficient sampling resistor (0.01%, 25ppm / degree) is used to generate a sampling voltage. The voltage across the sampling resistor (R2) connected in series with the battery is acquired via an analog-to-digital converter (U2), and the voltage (V) across the resistor and the operating current i are calculated. The real-time battery charge is calculated by Q1 = i (real-time battery current) * t (time). Based on the real-time charge Q1 and the current discharge curve M in the battery specifications, a certain mapping relationship exists between the real-time charge and the battery discharge curve, leading to the formula for the remaining battery charge: Q = f(Q1, M).

6. The high-precision handheld SF6 gas density detection device as described in claim 1, characterized in that: The gas line interface and the detection mechanism are detachable.

7. The method for detecting SF6 gas density using the high-precision handheld SF6 gas density detection device as described in claim 1 includes the following steps: Step S1: Use a handheld high-precision SF6 gas density detector to measure the temperature and pressure of the SF6 gas chamber of the electrical equipment under test; Step S2: Find the corresponding pressure threshold based on the detected temperature. If the detected pressure is less than or equal to the pressure threshold, then an SF6 gas leakage anomaly has occurred at the detection point; if the detected pressure is greater than the pressure threshold, there is no SF6 gas leakage. Step S3: When an SF6 gas leak is abnormal, the gas path information analysis module issues an alarm voice and displays the current temperature, pressure and gas density values.

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