Insulation quality evaluation method for C4CO2 mixed environment-friendly gas

Abstract

The invention belongs to the technical field of environment-friendly gas, and particularly relates to a C4C02 mixed environment-friendly gas insulation quality evaluation method which comprises the following steps: step 1, sample pretreatment: collecting a C4C02 gas sample with the proportion and purity meeting the evaluation requirement, and drying or filtering the C4C02 gas to remove impurities and moisture; 2, physical property determination: measuring the density of the sample by using a gas density meter, measuring the viscosity of gas by using a rheometer, measuring the thermal conductivity of the gas by using a thermal conductivity meter, and measuring the dielectric constant of the gas by using a dielectric constant tester; and step 3, breakdown voltage test: preparing high-voltage test equipment, installing an electrode, gradually increasing the voltage at a constant rate until gas breakdown occurs, and recording a breakdown voltage value and corresponding current change. Scientific basis can be provided for application of C4C02 gas, and wide application of the C4C02 gas in electrical insulating materials is promoted.

Description

Technical Field

[0001] The present invention belongs to the technical field of environmentally friendly gases, and in particular relates to a method for evaluating the insulation quality of a C4C02 mixed environmentally friendly gas. Background Art

[0002] C4C02 mixed environmentally friendly gas generally refers to an environmentally friendly gas mixture composed of multiple components, the core components of which include carbon dioxide (CO2) and other gases with low global warming potential (GWP), such as fluorinated gases (such as hydrofluorocarbons HFCs, fluoroolefins HFOs), nitrogen and argon, etc. This type of gas is designed to meet environmental protection needs, reduce environmental impact, and replace traditional high GWP gases in various applications.

[0003] In the field of refrigeration and air conditioning, C4C02 mixed environmentally friendly gases are used as substitutes to effectively reduce greenhouse gas emissions. For example, the Freon refrigerants that were widely used in the past are extremely destructive to the environment, and the use of environmentally friendly gases can significantly reduce the risk of damage to the ozone layer and reduce the impact of climate change. These gases usually have a lower GWP value, in many cases less than 500, which makes them a more sustainable choice.

[0004] In addition, these gases are widely used in fire extinguishing systems. Although traditional fire extinguishing agents, such as halons, are excellent in fire extinguishing effects, they cause great harm to the environment and human health. Therefore, using C4C02 mixed environmentally friendly gas as a substitute can not only ensure the fire extinguishing effect, but also reduce the impact on the environment, which is an ideal solution.

[0005] In the industrial field, the use of such mixed gases is equally important. They can be used as protective gases, driving gases or solvents in a variety of processes to improve production efficiency and reduce energy consumption. In addition, some environmentally friendly gases are made from renewable resources, which not only helps to reduce dependence on fossil fuels, but also reduces the overall carbon footprint.

[0006] The benefits of using C4C02 mixed environmentally friendly gas are also reflected in compliance. As global attention to greenhouse gas emissions continues to increase, international agreements such as the Kyoto Protocol and the Paris Agreement have been introduced to limit greenhouse gas emissions and promote the development of low-carbon technologies. The promotion and application of C4C02 mixed environmentally friendly gas complies with these regulatory requirements and helps companies achieve their sustainable development goals.

[0007] The existing gas insulation quality assessment method is relatively simple for C4C02 gas, and cannot comprehensively evaluate the gas's insulation performance, monitor the gas's stability under extreme conditions, and is insufficient in assessing the gas's adaptability under different environmental conditions. Therefore, we propose a C4C02 mixed environmentally friendly gas insulation quality assessment method to solve the above problems. Summary of the invention

[0008] The purpose of the present invention is to provide a method for evaluating the insulation quality of C4C02 mixed environmentally friendly gas, which can provide a scientific basis for the application of C4C02 gas and promote its widespread application in electrical insulation materials.

[0009] The technical solution adopted by the present invention is as follows:

[0010] A method for evaluating the insulation quality of a C4C02 mixed environmentally friendly gas, the evaluation method comprising the following steps:

[0011] Step 1. Sample pretreatment: Collect C4C02 gas samples at a ratio and purity that meets the evaluation requirements, dry or filter the C4C02 gas to remove impurities and moisture;

[0012] Step 2. Physical property measurement: use a gas density meter to measure the density of the sample, use a rheometer to measure the viscosity of the gas, use a thermal conductivity meter to measure the thermal conductivity of the gas, and use a dielectric constant tester to measure the dielectric constant of the gas;

[0013] Step 3. Breakdown voltage test: prepare high voltage test equipment and install electrodes, gradually increase the voltage at a constant rate until the gas breaks down, and record the breakdown voltage value and the corresponding current change;

[0014] Step 4. Dielectric strength measurement: apply a certain voltage in the gas and maintain it for a certain time; apply a certain voltage in the gas and maintain it for a certain time;

[0015] Step 5. Temperature change test: Conduct electrical property tests at different temperatures to observe changes in gas performance;

[0016] Step 6. Pressure change test: Test the insulation performance of the gas under different pressure conditions and record the relevant data;

[0017] Step 7. Chemical stability test: expose the gas to high temperature and observe the changes in its physical and chemical properties. Under high voltage, check whether the gas will decompose or produce harmful substances.

[0018] Step 8. Long-term aging test: Continue to test the gas under specific conditions for several weeks or months, regularly extract gas samples, measure their electrical and physical properties, and observe performance changes;

[0019] Step 9. Data analysis and evaluation: Organize all measurement results into tables, use statistical and chart analysis software to conduct in-depth analysis of the data, judge the insulation quality of the gas, compare the test results with relevant standards and specifications, and evaluate whether the gas performance meets the requirements.

[0020] In a preferred embodiment, the sample pretreatment also includes using a corrosion-resistant, well-sealed gas bottle to store C4C02 gas, using activated carbon or a microporous filter to remove solid particles and harmful substances, connecting the gas bottle to the filter, slowly passing the gas into the filter, guiding the airflow to pass the gas through the filter to remove impurities, using a gas dryer to remove moisture from the gas, cooling the gas to a low temperature to condense the moisture, and draining the water through a drain valve, using a hygrometer or a dew point meter to monitor the moisture content in the gas, transferring the pretreated gas to a clean, dry storage container, and after the gas is collected, conducting a small-scale sampling test to confirm that the purity and composition of the gas meet the experimental requirements.

[0021] In a preferred embodiment, the physical property determination further includes selecting a gas densitometer, slowly filling the pretreated C4C02 gas into the densitometer, recording the temperature and pressure of the gas, reading the reading on the densitometer, and making necessary corrections, recording the measured density value in the experimental log, and indicating the test conditions, selecting a rotational rheometer or a capillary rheometer, filling the gas sample into the measuring chamber of the rheometer, setting the test parameters according to the instrument instructions, including shear rate and temperature, starting the instrument, recording the viscosity values ​​at different shear rates, analyzing the trend of viscosity change with shear rate, and calculating the effective viscosity, selecting a laser thermal conductivity meter or a static thermal conductivity meter, filling the gas sample into the thermal conductivity measurement chamber, setting the temperature and pressure conditions of the thermal conductivity meter, starting the instrument, recording the thermal conductivity value at a specific temperature, correcting the measurement data, calculating the thermal conductivity of the gas, and recording it in the experimental log.

[0022] In a preferred embodiment, the breakdown voltage test also includes selecting a high voltage generator or transformer, selecting an electrode material, including aluminum, copper or stainless steel, fixing the electrode in the test cavity according to the test requirements, connecting the high voltage test equipment to the power supply, checking the stability and output capacity of the power supply, slowly filling the pre-treated C4C02 gas into the test cavity, using an appropriate pressure gauge to monitor the gas pressure in the cavity, setting the initial voltage and pressurization rate on the high voltage equipment, selecting a lower initial voltage and gradually increasing it at 1 kV / s, connecting an ammeter or oscilloscope, monitoring the current change in real time, starting the high voltage generator, starting to gradually increase the voltage, monitoring the current change, when the current suddenly increases and the voltage reaches the breakdown point, recording the voltage value, confirming the breakdown phenomenon, immediately stopping the pressurization to protect the equipment, recording the breakdown voltage value, current value and test conditions in detail, performing multiple tests, and summarizing all test data.

[0023] In a preferred embodiment, the dielectric strength determination further includes selecting a high voltage test device and a voltmeter, an ammeter, and an oscilloscope to monitor the changes in voltage and current, filling the pre-treated C4C02 gas into the test cavity, using a pressure gauge to monitor and adjust the pressure in the cavity to keep it within a set range, setting the constant voltage to be applied according to the experimental design, connecting the high voltage test device to the power supply, and adjusting the device parameters as needed, starting the device, applying a constant voltage in the gas, and using an ammeter or an oscilloscope to monitor the changes in current during the entire test process. The breakdown phenomenon is accompanied by a sudden change in current. If a sudden increase in current is observed, it means that the gas medium has broken down, and the voltage application is stopped immediately, and the voltage value applied during the breakdown is recorded, and the influence of temperature and air pressure factors on the test results is considered;

[0024] Calculate dielectric strength: E = V / d;

[0025] Where E is the dielectric strength, V is the breakdown voltage, and d is the distance between the electrodes.

[0026] In a preferred embodiment, the temperature change test also includes setting a temperature control system, which is a constant temperature bath or an environmental test chamber, setting different test temperature points, and the test temperature points are -40°C, 20°C, and 100°C. In the environmental test chamber, the gas sample is filled into the test cavity, and at each temperature, a predetermined voltage is applied, and the current and other electrical properties are recorded. During the process of applying the voltage, the current change is monitored in real time, and the electrical test results at each temperature are recorded, including the breakdown voltage, dielectric strength, and leakage current. The electrical performance data at different temperatures are compared to evaluate the adaptability and stability of the gas under different environmental conditions.

[0027] In a preferred embodiment, the pressure change test also includes preparing high-voltage test equipment, pressure measuring instruments and electrical measuring instruments, using a pressure regulator and a gas supply system, setting different test pressure points, including normal pressure, 0.5atm, 1.5atm and 3atm, and keeping the gas stable at the pressure for a certain period of time at each set pressure point. Under each pressure condition, a predetermined voltage is applied and the current change is monitored. The current change is monitored in real time, and whether a breakdown occurs under the applied voltage is recorded. The test results under each pressure condition are recorded in detail, including the breakdown voltage, dielectric strength and leakage current, and the electrical performance data under different pressures are compared to evaluate the changing trend of the gas insulation performance.

[0028] In a preferred embodiment, the chemical stability test also includes preparing a high-temperature furnace or a high-temperature environmental box, setting the temperature range of the high-temperature furnace, the temperature range includes 200°C, 300°C, and 400°C, allowing the gas to stabilize under high temperature conditions for a period of time, monitoring the physical changes and chemical properties of the gas at high temperature, recording whether the gas has signs of decomposition or reaction to produce new substances, setting electrodes and electrolytes in the electrochemical testing equipment, setting a high-voltage power supply, gradually applying voltage, monitoring current changes, observing the decomposition of the gas under the action of voltage, recording whether harmful substances are generated, and using gas chromatography or mass spectrometry to detect reaction products.

[0029] In a preferred embodiment, the long-term aging test also includes determining the specific conditions of the long-term aging test, which are high temperature, high pressure, and constant pressure. Starting a high-voltage power supply, applying a predetermined voltage, and maintaining it for several weeks or months, determining the time interval for regular sampling, and sampling once a week or month. After each sampling, measuring the electrical properties and physical properties of the gas sample, organizing the test data at each time point during the long-term aging process into tables or charts, analyzing the trend of gas performance changes over time, and evaluating the aging degree and stability of the gas under long-term high temperature and high pressure conditions.

[0030] In a preferred embodiment, the long-term aging test also includes determining the specific conditions of the long-term aging test, which are high temperature, high pressure, and constant pressure. Starting a high-voltage power supply, applying a predetermined voltage, and maintaining it for several weeks or months, determining the time interval for regular sampling, and sampling once a week or month. After each sampling, measuring the electrical properties and physical properties of the gas sample, organizing the test data at each time point during the long-term aging process into tables or charts, analyzing the trend of gas performance changes over time, and evaluating the aging degree and stability of the gas under long-term high temperature and high pressure conditions.

[0031] The technical effects achieved by the present invention are:

[0032] The evaluation method covers sample pretreatment, physical property determination, breakdown voltage test, dielectric strength determination, temperature and pressure change test, chemical stability test and long-term aging test, ensuring a comprehensive understanding of the insulation performance of the gas. By setting clear steps and conditions, the test process can be standardized, which facilitates comparison and reproduction between different laboratories and improves the credibility of the test results.

[0033] Systematic organization and statistical analysis of test data can help to deeply understand the relationship between gas performance and external conditions, support scientific decision-making, and monitor the stability of gas under extreme conditions through long-term aging tests, provide data support for subsequent applications and improvements, and adopt appropriate equipment and protective measures to ensure safe operation in high-pressure and high-temperature tests and reduce experimental risks;

[0034] Temperature and pressure change tests can evaluate the adaptability of gases under different environmental conditions, ensure their reliability in practical applications, and detect the chemical stability of gases at high temperatures to ensure that they do not produce harmful substances in high-voltage environments, thereby ensuring environmental and equipment safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of a method for evaluating the insulation quality of a C4C02 mixed environmentally friendly gas according to the present invention. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0037] See also Figure 1 As shown, the present invention provides a method for evaluating the insulation quality of a C4C02 mixed environmentally friendly gas, the evaluation method comprising the following steps:

[0038] Step 1. Sample pretreatment: Collect C4C02 gas samples at a ratio and purity that meets the evaluation requirements, dry or filter the C4C02 gas to remove impurities and moisture;

[0039] Step 2. Physical property measurement: use a gas density meter to measure the density of the sample, use a rheometer to measure the viscosity of the gas, use a thermal conductivity meter to measure the thermal conductivity of the gas, and use a dielectric constant tester to measure the dielectric constant of the gas;

[0040] Step 3. Breakdown voltage test: prepare high voltage test equipment and install electrodes, gradually increase the voltage at a constant rate until the gas breaks down, and record the breakdown voltage value and the corresponding current change;

[0041] Step 4. Dielectric strength measurement: apply a certain voltage in the gas and maintain it for a certain time; apply a certain voltage in the gas and maintain it for a certain time;

[0042] Step 5. Temperature change test: Conduct electrical property tests at different temperatures to observe changes in gas performance;

[0043] Step 6. Pressure change test: Test the insulation performance of the gas under different pressure conditions and record the relevant data;

[0044] Step 7. Chemical stability test: expose the gas to high temperature and observe the changes in its physical and chemical properties. Under high voltage, check whether the gas will decompose or produce harmful substances.

[0045] Step 8. Long-term aging test: Continue to test the gas under specific conditions for several weeks or months, regularly extract gas samples, measure their electrical and physical properties, and observe performance changes;

[0046] Step 9. Data analysis and evaluation: Organize all measurement results into tables, use statistical and chart analysis software to conduct in-depth analysis of the data, judge the insulation quality of the gas, compare the test results with relevant standards and specifications, and evaluate whether the gas performance meets the requirements.

[0047] Sample pretreatment also includes using corrosion-resistant, well-sealed gas bottles to store C4C02 gas, using activated carbon or microporous filters to remove solid particles and harmful substances, connecting the gas bottle to the filter, slowly passing the gas into the filter, guiding the airflow to pass the gas through the filter to remove impurities, using a gas dryer to remove moisture from the gas, cooling the gas to a low temperature to condense the moisture, and draining the water through a drain valve, using a hygrometer or dew point meter to monitor the moisture content in the gas, transferring the pretreated gas to a clean, dry storage container, and after the gas is collected, conducting small-scale sampling and testing to confirm that the purity and composition of the gas meet the experimental requirements.

[0048] The physical property determination also includes selecting a gas densitometer, slowly filling the pretreated C4C02 gas into the densitometer, recording the temperature and pressure of the gas, reading the readings on the densitometer, and making necessary corrections, recording the measured density value in the experimental log and indicating the test conditions, selecting a rotational rheometer or a capillary rheometer, filling the gas sample into the measurement chamber of the rheometer, setting the test parameters according to the instrument instructions, including shear rate and temperature, starting the instrument, recording the viscosity values ​​at different shear rates, analyzing the trend of viscosity change with shear rate, and calculating the effective viscosity, selecting a laser thermal conductivity meter or a static method thermal conductivity meter, filling the gas sample into the thermal conductivity measurement chamber, setting the temperature and pressure conditions of the thermal conductivity meter, starting the instrument, recording the thermal conductivity value at a specific temperature, correcting the measurement data, calculating the thermal conductivity of the gas, and recording it in the experimental log.

[0049] The breakdown voltage test also includes selecting a high-voltage generator or transformer, selecting electrode materials, including aluminum, copper or stainless steel, fixing the electrodes in the test chamber according to the test requirements, connecting the high-voltage test equipment to the power supply, checking the stability and output capacity of the power supply, slowly filling the pre-treated C4C02 gas into the test chamber, using an appropriate pressure gauge to monitor the gas pressure in the chamber, setting the initial voltage and pressurization rate on the high-voltage equipment, selecting a lower initial voltage and gradually increasing it at 1kV / s, connecting an ammeter or oscilloscope, monitoring the current changes in real time, starting the high-voltage generator, and starting to gradually increase the voltage, monitoring the current changes, when the current suddenly increases and the voltage reaches the breakdown point, record the voltage value, and after confirming the breakdown phenomenon, immediately stop pressurizing to protect the equipment, record the breakdown voltage value, current value and test conditions in detail, conduct multiple tests, and summarize all test data.

[0050] The dielectric strength measurement also includes selecting high voltage test equipment and voltmeter, ammeter, oscilloscope, monitoring the changes of voltage and current, filling the pre-treated C4C02 gas into the test chamber, using a pressure gauge to monitor and adjust the pressure in the chamber to keep it within the set range, setting the constant voltage to be applied according to the experimental design, connecting the high voltage test equipment to the power supply, and adjusting the equipment parameters as needed, starting the equipment, applying a constant voltage in the gas, and using an ammeter or oscilloscope to monitor the changes in current during the entire test process. The breakdown phenomenon is accompanied by a sudden change in current. If a sudden increase in current is observed, it means that the gas medium has broken down, and the voltage application is stopped immediately. The voltage value applied during the breakdown is recorded, and the influence of temperature and air pressure factors on the test results is considered;

[0051] Calculate dielectric strength: E = V / d;

[0052] Where E is the dielectric strength, V is the breakdown voltage, and d is the distance between the electrodes.

[0053] The temperature change test also includes setting a temperature control system. The temperature control system is a constant temperature bath or an environmental test chamber. Different test temperature points are set at -40°C, 20°C, and 100°C. In the environmental test chamber, the gas sample is filled into the test cavity. At each temperature, a predetermined voltage is applied, and the current and other electrical properties are recorded. During the voltage application process, the current change is monitored in real time, and the electrical test results at each temperature are recorded, including breakdown voltage, dielectric strength, and leakage current. The electrical performance data at different temperatures are compared to evaluate the adaptability and stability of the gas under different environmental conditions.

[0054] The pressure change test also includes preparing high-voltage test equipment, pressure measuring instruments and electrical measuring instruments, using pressure regulators and gas supply systems, setting different test pressure points, including normal pressure, 0.5atm, 1.5atm and 3atm, and keeping the gas stable at the pressure for a certain period of time at each set pressure point. Under each pressure condition, a predetermined voltage is applied and the current change is monitored. The current change is monitored in real time, and whether a breakdown occurs under the applied voltage is recorded. The test results under each pressure condition are recorded in detail, including the breakdown voltage, dielectric strength and leakage current. The electrical performance data under different pressures are compared to evaluate the changing trend of the gas insulation performance.

[0055] The chemical stability test also includes preparing a high-temperature furnace or a high-temperature environmental chamber, setting the temperature range of the high-temperature furnace, including 200°C, 300°C, and 400°C, allowing the gas to stabilize under high-temperature conditions for a period of time, monitoring the physical changes and chemical properties of the gas at high temperatures, and recording whether the gas has signs of decomposition or reaction to produce new substances. Electrodes and electrolytes are set in electrochemical testing equipment, a high-voltage power supply is set, voltage is gradually applied, current changes are monitored, and the decomposition of the gas under voltage is observed. Record whether any harmful substances are generated, and use gas chromatography or mass spectrometry to detect reaction products.

[0056] The long-term aging test also includes determining the specific conditions of the long-term aging test, which are high temperature, high pressure, and constant pressure. Starting a high-voltage power supply, applying a predetermined voltage, and maintaining it for weeks or months, determining the time interval for regular sampling, sampling once a week or month, and measuring the electrical and physical properties of the gas sample after each sampling. The test data at each time point in the long-term aging process are organized into tables or charts, analyzing the trend of gas performance changes over time, and evaluating the aging degree and stability of the gas under long-term high temperature and high pressure conditions.

[0057] The long-term aging test also includes determining the specific conditions of the long-term aging test, which are high temperature, high pressure, and constant pressure. Starting a high-voltage power supply, applying a predetermined voltage, and maintaining it for weeks or months, determining the time interval for regular sampling, sampling once a week or month, and measuring the electrical and physical properties of the gas sample after each sampling. The test data at each time point in the long-term aging process are organized into tables or charts, analyzing the trend of gas performance changes over time, and evaluating the aging degree and stability of the gas under long-term high temperature and high pressure conditions.

[0058] In the present invention, the evaluation method covers sample pretreatment, physical property determination, breakdown voltage test, dielectric strength determination, temperature and pressure change test, chemical stability test and long-term aging test, ensuring a comprehensive understanding of the insulation performance of the gas. By setting clear steps and conditions, the test process can be standardized, which is convenient for comparison and reproduction between different laboratories and improves the credibility of the test results.

[0059] Systematic organization and statistical analysis of test data can help to deeply understand the relationship between gas performance and external conditions, support scientific decision-making, and monitor the stability of gas under extreme conditions through long-term aging tests, provide data support for subsequent applications and improvements, and adopt appropriate equipment and protective measures to ensure safe operation in high-pressure and high-temperature tests and reduce experimental risks;

[0060] Temperature and pressure change tests can evaluate the adaptability of gases under different environmental conditions, ensure their reliability in practical applications, and detect the chemical stability of gases at high temperatures to ensure that they do not produce harmful substances in high-voltage environments, thereby ensuring environmental and equipment safety.

[0061] The above is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention shall be implemented according to the conventional means in the art unless otherwise specified and limited.

Claims

1. A method for evaluating the insulation quality of C4C02 mixed environmentally friendly gas, characterized in that: The evaluation methodology includes the following steps: Step 1. Sample pretreatment: Collect C4C02 gas samples at a ratio and purity that meets the evaluation requirements, dry or filter the C4C02 gas to remove impurities and moisture; Step 2. Physical property measurement: use a gas density meter to measure the density of the sample, use a rheometer to measure the viscosity of the gas, use a thermal conductivity meter to measure the thermal conductivity of the gas, and use a dielectric constant tester to measure the dielectric constant of the gas; Step 3. Breakdown voltage test: prepare high voltage test equipment and install electrodes, gradually increase the voltage at a constant rate until the gas breaks down, and record the breakdown voltage value and the corresponding current change; Step 4. Dielectric strength measurement: Apply a certain voltage in the gas and maintain it for a certain time; Step 5. Temperature change test: Conduct electrical property tests at different temperatures to observe changes in gas performance; Step 6. Pressure change test: Test the insulation performance of the gas under different pressure conditions and record the relevant data; Step 7. Chemical stability test: expose the gas to high temperature and observe the changes in its physical and chemical properties. Under high voltage, check whether the gas will decompose or produce harmful substances. Step 8. Long-term aging test: Continue to test the gas under specific conditions for several weeks or months, regularly extract gas samples, measure their electrical and physical properties, and observe performance changes; Step 9. Data analysis and evaluation: Organize all measurement results into tables, use statistical and chart analysis software to conduct in-depth analysis of the data, judge the insulation quality of the gas, compare the test results with relevant standards and specifications, and evaluate whether the gas performance meets the requirements.

2. The insulation quality evaluation method of a C4C02 mixed environmentally friendly gas according to claim 1 is characterized in that: The sample pretreatment also includes using a corrosion-resistant, well-sealed gas bottle to store C4C02 gas, using activated carbon or a microporous filter to remove solid particles and harmful substances, connecting the gas bottle to the filter, slowly passing the gas into the filter, guiding the gas flow to pass the filter to remove impurities, using a gas dryer to remove moisture from the gas, cooling the gas to a low temperature to condense the moisture, and draining the water through a drain valve, using a hygrometer or a dew point meter to monitor the moisture content in the gas, transferring the pretreated gas to a clean, dry storage container, and after the gas is collected, conducting a small-scale sampling test to confirm that the purity and composition of the gas meet the experimental requirements.

3. The insulation quality evaluation method of a C4C02 mixed environmentally friendly gas according to claim 1, characterized in that: The physical property determination also includes selecting a gas densitometer, slowly filling the pretreated C4C02 gas into the densitometer, recording the temperature and pressure of the gas, reading the reading on the densitometer, and making necessary corrections, recording the measured density value in the experimental log, and indicating the test conditions, selecting a rotational rheometer or a capillary rheometer, filling the gas sample into the measurement chamber of the rheometer, setting the test parameters according to the instrument instructions, including shear rate and temperature, starting the instrument, recording the viscosity values ​​at different shear rates, analyzing the trend of viscosity changing with shear rate, and calculating the effective viscosity, selecting a laser thermal conductivity meter or a static method thermal conductivity meter, filling the gas sample into the thermal conductivity measurement chamber, setting the temperature and pressure conditions of the thermal conductivity meter, starting the instrument, recording the thermal conductivity value at a specific temperature, correcting the measurement data, calculating the thermal conductivity of the gas, and recording it in the experimental log.

4. The insulation quality evaluation method of a C4C02 mixed environmentally friendly gas according to claim 1 is characterized in that: The breakdown voltage test also includes selecting a high voltage generator or transformer, selecting electrode materials, including aluminum, copper or stainless steel, fixing the electrodes in the test cavity according to the test requirements, connecting the high voltage test equipment to the power supply, checking the stability and output capacity of the power supply, slowly filling the pre-treated C4C02 gas into the test cavity, using an appropriate pressure gauge to monitor the gas pressure in the cavity, setting the initial voltage and pressurization rate on the high voltage equipment, selecting a lower initial voltage and gradually increasing it at 1kV / s, connecting an ammeter or oscilloscope, monitoring the current change in real time, starting the high voltage generator, starting to gradually increase the voltage, monitoring the current change, when the current suddenly increases and the voltage reaches the breakdown point, recording the voltage value, after confirming the breakdown phenomenon, immediately stopping the pressurization to protect the equipment, recording the breakdown voltage value, current value and test conditions in detail, performing multiple tests, and summarizing all test data.

5. The insulation quality evaluation method of a C4C02 mixed environmentally friendly gas according to claim 1, characterized in that: The dielectric strength determination also includes selecting a high voltage test device and a voltmeter, an ammeter, and an oscilloscope to monitor the changes in voltage and current, filling the pre-treated C4C02 gas into the test cavity, using a pressure gauge to monitor and adjust the pressure in the cavity to keep it within a set range, setting the constant voltage to be applied according to the experimental design, connecting the high voltage test device to a power source, and adjusting the device parameters as needed, starting the device, applying a constant voltage in the gas, and using an ammeter or an oscilloscope to monitor the changes in current during the entire test process. The breakdown phenomenon is accompanied by a sudden change in current. If a sudden increase in current is observed, it means that the gas medium has broken down, and the voltage application is stopped immediately, and the voltage value applied during the breakdown is recorded, and the influence of temperature and air pressure factors on the test results is considered; Calculate dielectric strength: E = V / d; Where E is the dielectric strength, V is the breakdown voltage, and d is the distance between the electrodes.

6. The insulation quality evaluation method of a C4C02 mixed environmentally friendly gas according to claim 1 is characterized in that: The temperature change test also includes setting a temperature control system, which is a constant temperature bath or an environmental test chamber, setting different test temperature points, and the test temperature points are -40°C, 20°C, and 100°C. In the environmental test chamber, the gas sample is filled into the test cavity, and at each temperature, a predetermined voltage is applied, and the current and other electrical properties are recorded. During the process of applying the voltage, the current change is monitored in real time, and the electrical test results at each temperature are recorded, including the breakdown voltage, dielectric strength, and leakage current. The electrical performance data at different temperatures are compared to evaluate the adaptability and stability of the gas under different environmental conditions.

7. The insulation quality evaluation method of a C4C02 mixed environmentally friendly gas according to claim 1, characterized in that: The pressure change test also includes preparing high-voltage test equipment, pressure measuring instruments and electrical measuring instruments, using a pressure regulator and a gas supply system, setting different test pressure points, including normal pressure, 0.5atm, 1.5atm and 3atm, and keeping the gas stable at the pressure for a certain period of time at each set pressure point. Under each pressure condition, a predetermined voltage is applied and the current change is monitored. The current change is monitored in real time, and whether a breakdown occurs under the applied voltage is recorded. The test results under each pressure condition are recorded in detail, including the breakdown voltage, dielectric strength and leakage current, and the electrical performance data under different pressures are compared to evaluate the changing trend of the gas insulation performance.

8. The insulation quality evaluation method of a C4C02 mixed environmentally friendly gas according to claim 1, characterized in that: The chemical stability test also includes preparing a high-temperature furnace or a high-temperature environmental chamber, setting the temperature range of the high-temperature furnace, including 200°C, 300°C, and 400°C, allowing the gas to stabilize under high temperature conditions for a period of time, monitoring the physical changes and chemical properties of the gas at high temperatures, recording whether the gas has signs of decomposition or reaction to produce new substances, setting electrodes and electrolytes in electrochemical testing equipment, setting a high-voltage power supply, gradually applying voltage, monitoring current changes, observing the decomposition of the gas under the action of voltage, recording whether harmful substances are generated, and using gas chromatography or mass spectrometry to detect reaction products.

9. The insulation quality evaluation method of a C4C02 mixed environmentally friendly gas according to claim 1, characterized in that: The long-term aging test also includes determining specific conditions for the long-term aging test, which are high temperature, high pressure, and constant pressure. Starting a high-voltage power supply, applying a predetermined voltage, and maintaining it for weeks or months, determining the time interval for regular sampling, sampling once a week or month, and measuring the electrical properties and physical properties of the gas sample after each sampling. The test data at each time point during the long-term aging process are organized into tables or charts, analyzing the trend of gas performance changes over time, and evaluating the aging degree and stability of the gas under long-term high temperature and high pressure conditions.

10. The insulation quality evaluation method of a C4C02 mixed environmentally friendly gas according to claim 1, characterized in that: The data analysis and evaluation also includes summarizing the measurement results of all test processes, including temperature, pressure, electrical performance and physical properties, storing the sorted data in a spreadsheet software or database, identifying and processing missing values ​​or outliers, using statistical software to calculate basic statistics of each data, including mean, standard deviation, extreme values, analyzing the changing trend of gas performance, and using regression analysis or variance analysis methods to evaluate the relationship between influencing factors and performance.

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